Introduction to the Framework Classes Part 4 - the Final Chapter Introduction
In Part 1 of this series, I mentioned that my journey into the world of MIDI remote scripts began with a search for a better way of integrating my FCB1010 foot cont roller into my Live setup. Well, it’s been a fun trip - with lots of interesting side investigations along the way - but now we’ve come full circle and it’s time to finish up what I set out to do in the beginning. In this article, we’ll have a look a coupl e of new _Framework methods introduced in version 8.1.3, which will allow us to operate scripts in Combination Mode, Mode, and we’ll create a generic script which will allow the FCB1010 to work in concert with the APC40 – in fact, we’ll set it up to emulate the APC40. And then we’re pretty much d one. Let’s start with combination mode. Combination Mode – red and yellow and pink and green…
As we saw in Part 1, set_show_highlight , a SessionComponent method, can be used to display the famous “red box”, which represents the portion of a Session View which a control surface is controlling. First see n with the APC40 and Launchpad, the red box is a must have for any clip launcher. New since 8.1.4, however, is a functional Combination Mode – specifically announced for the APC40 and A PC20 – which “glues” two or more session highlights together. From the 8.1.4 changelog: “Combination Mode is now active when multiple Akai APC40/20s are in use. This means that the topmost controller selected in your preferences will control tracks 1-8, the second controller selected will control tracks 9-16, 9-16, and so on.”
Sounds like fun – let’s see how it’s done. By looking through the APC sources, we can work our way back to the essential change at work here: the SessionComponent class now has new methods called _link and _unlink (together with a new attribute _is_linked _is_linked , and a new list object known as _linked_session_instan _linked_session_instances ces ). Linking sessions turns out to be no more difficult than calling the SessionComponent’s SessionComponent’s _link method, as follows: session = SessionComponent(num_tracks, num_scenes) session. session._link()
Now, although multiple session boxes can be linked in this way, we need to manage our session offsets, if we want our sessions to sit beside each other, and not one on top of the other. In other words, we will need to sequentially assign non-zero offsets to our linked sessions, based on the adjacent session’s width. We'll add the required code to the ProjectX script from Part 1, as an illustration. First, we’ll need a list object to hold the active instances of our ProjectX ControlSurface class, and a static method which will be called at the end of initialisation: _active_instances = []
def _combine_active_instances(): _combine_active_instances(): track_offset = 0 for instance in ProjectX. ProjectX._active_instances: instance. instance._activate_combination_mode(track_offset) track_offset += += session session. .width() _combine_active_instances = staticmethod staticmethod(_combine_active_instances) (_combine_active_instances) _do_combine call at the end of our init sequence, which in turn calls We add a _do_combine the _combine_active_instanc _combine_active_instances es static method – and _combine_active_inst _combine_active_instances ances calls _activate_combination_ _activate_combination_mode mode on each instance.
def _do_combine( _do_combine(self self): ): if self not in ProjectX. ProjectX._active_instances: ProjectX. ProjectX._active_instances _active_instances. .append(self append(self) ) ProjectX. ProjectX._combine_active_instances() def _activate_combination_mode( _activate_combination_mode(self self, , track_offset): if session. session._is_linked(): session. session._unlink() session. session.set_offsets(track_offset, 0) session. session._link() Now that the linking is all set up, we’ll define a _do_uncombin a _do_uncombine e method, to clean things up when we disconnect; we’ll unlink our SessionComponent and remove ourselves from the list of active instances here.
def _do_uncombine( _do_uncombine(self self): ): if (( ((self self in ProjectX. ProjectX._active_instances) and ProjectX. ProjectX._active_instances _active_instances. .remove(self remove(self)): )): self. self ._session. _session.unlink() ProjectX. ProjectX._combine_active_instances() def disconnect( disconnect(self self): ): self. self ._do_uncombine() ControlSurface. ControlSurface.disconnect(self disconnect(self) ) So here’s what we get when we load several instances of our new ProjectX script via Live's MIDI preferences dialog:
The session highlights are all linked (with an automatic track offset for each instance, which matches the adjacent session highlight width), and when we move any one of them, the others move along together. together. By _activate_combination_mode ode , we can get them to stack changing the offsets in _activate_combination_m s tack side-by-side, or one above the other, or if we wanted to, we could indeed stack them one on top of the other . By stacking them one on top of the other, we can control a si ngle session highlight zone wi th multiple controllers – which is exactly what we want to do with th e APC40 and FCB1010 in combination mode. As of version 8.1.3, the Framework s cripts have included support for session linking, but so far, the only official scripts which implement combination mode are the APC scripts (as of 8.1.4). As shown above, however, support for combination mode can be extended to pretty much any Framework -based script. What we want to create then, is a script which will allow the FCB1010 to operate in combination mode together with the APC40. Let’s build one.
def _do_combine( _do_combine(self self): ): if self not in ProjectX. ProjectX._active_instances: ProjectX. ProjectX._active_instances _active_instances. .append(self append(self) ) ProjectX. ProjectX._combine_active_instances() def _activate_combination_mode( _activate_combination_mode(self self, , track_offset): if session. session._is_linked(): session. session._unlink() session. session.set_offsets(track_offset, 0) session. session._link() Now that the linking is all set up, we’ll define a _do_uncombin a _do_uncombine e method, to clean things up when we disconnect; we’ll unlink our SessionComponent and remove ourselves from the list of active instances here.
def _do_uncombine( _do_uncombine(self self): ): if (( ((self self in ProjectX. ProjectX._active_instances) and ProjectX. ProjectX._active_instances _active_instances. .remove(self remove(self)): )): self. self ._session. _session.unlink() ProjectX. ProjectX._combine_active_instances() def disconnect( disconnect(self self): ): self. self ._do_uncombine() ControlSurface. ControlSurface.disconnect(self disconnect(self) ) So here’s what we get when we load several instances of our new ProjectX script via Live's MIDI preferences dialog:
The session highlights are all linked (with an automatic track offset for each instance, which matches the adjacent session highlight width), and when we move any one of them, the others move along together. together. By _activate_combination_mode ode , we can get them to stack changing the offsets in _activate_combination_m s tack side-by-side, or one above the other, or if we wanted to, we could indeed stack them one on top of the other . By stacking them one on top of the other, we can control a si ngle session highlight zone wi th multiple controllers – which is exactly what we want to do with th e APC40 and FCB1010 in combination mode. As of version 8.1.3, the Framework s cripts have included support for session linking, but so far, the only official scripts which implement combination mode are the APC scripts (as of 8.1.4). As shown above, however, support for combination mode can be extended to pretty much any Framework -based script. What we want to create then, is a script which will allow the FCB1010 to operate in combination mode together with the APC40. Let’s build one.
FCB1020 - a new script for the FCB1010
The first thing to do when setting out to create a new script is to decide on a functional layout. If we know what we’re trying to achieve in terms of functionality and operation - before we touch a line of code - we can save ourselves a good deal of time down t he road. In this case, we’re looking for an arrangement which will allow the FCB1010 to mirror the operation of the APC40, in so far as possible, and allow a llow for optimized hands-free operation. Although the options for designing a control script are almost unlimited, generally, the resulting method of operation needs to be intuitive. The FCB1010 has some built-in constraints, but also offers a great deal of flexibility. We have 10 banks of 10 switches and 2 pedals to work with – equivalent to 100 “button” controls and 20 “sliders”. Interestingly, the APC40 has a similar number of buttons and knobs. If we look at the two controllers side -by-side, a pattern emerges. Each column of the APC40’s grid consists of 5 clip launch buttons (one per scene) and 5 track control buttons (clip stop, track select, activate, activate, solo, & record). Each of the FCB1010’s 10 banks has 5 switches on the top row, and 5 switches on the bottom row. Based on this parallel, if we assign one FCB1010 bank to each of the APC40’s track columns, the resulting operation will indeed be intuitive, and will closely follow the APC’s layout. We only have 2 pedals per bank, however, so we’ll map them to Track Volume, and Send A – at least for now. Here’s how a typical FCB1010 bank will lay out, together with the A PC40 layout for comparison.
Bank 01
APC40
We’ll use this layout for banks 1 through 8 (since the APC40 has 8 track control columns), but because the
FCB1010 has 10 banks in total, we have 2 banks left over. Let’s use bank 00 for the Master Track controls, and the scene launch controls, in a similar arrangement to banks 1 t hrough 8. There are no activate, solo or record buttons for the master track, so instead, we’ll map global play, stop and record here:
Bank 00
Now we only have one bank left - bank 09. We’ll use bank 09 for session and track navigation, and for device control. Here’s how it will look:
Bank 09
Although fairly intuitive, the layout described above might not suit everyone’s preferences. Wouldn’t it be nice if the end user could decide on his or her own preferred layout? Live’s User Remote Scripts allow for this kind of thing, so we’ll take a similar approach. Rather than hard -coding the note and controller mappings deep within our new script, we’ll pull all of the assignments out into a separate file, for easy access and editing. It will rem ain a python .py file (not a .txt file) - in the tradition of consts.py, of Mackie emulation fame - but since .py files are simple text files, they can be edited using any te xt editor. We’ll call our file MIDI_map.py . Here’s a sample of what it will contain:
# General PLAY = 7 #Global play STOP = 8 #Global stop REC = 9 #Global record TAPTEMPO = -1 #Tap tempo NUDGEUP = -1 #Tempo Nudge Up NUDGEDOWN = -1 #Tempo Nudge Down UNDO = -1 #Undo REDO = -1 #Redo LOOP = -1 #Loop on/off PUNCHIN = -1 #Punch in PUNCHOUT = -1 #Punch out OVERDUB = -1 #Overdub on/off METRONOME = -1 #Metronome on/off RECQUANT = -1 #Record quantization on/off DETAILVIEW = -1 #Detail view switch CLIPTRACKVIEW = -1 #Clip/Track view switch
# Device Control DEVICELOCK = 99 #Device Lock (lock "blue hand") DEVICEONOFF = 94 #Device on/off DEVICENAVLEFT = 92 #Device nav left DEVICENAVRIGHT = 93 #Device nav right DEVICEBANKNAVLEFT = -1 #Device bank nav left DEVICEBANKNAVRIGHT = -1 #Device bank nav right # Arrangement View Controls SEEKFWD = -1 #Seek forward SEEKRWD = -1 #Seek rewind # Session Navigation (aka "red box") SESSIONLEFT = 95 #Session left SESSIONRIGHT = 96 #Session right SESSIONUP = -1 #Session up SESSIONDOWN = -1 #Session down ZOOMUP = 97 #Session Zoom up ZOOMDOWN = 98 #Session Zoom down ZOOMLEFT = -1 #Session Zoom left ZOOMRIGHT = -1 #Session Zoom right # Track Navigation TRACKLEFT = 90 #Track left TRACKRIGHT = 91 #Track right # Scene Navigation SCENEUP = -1 #Scene down SCENEDN = -1 #Scene up # Scene Launch SELSCENELAUNCH = -1 #Selected scene launch Now we can easily change the layout of any of our banks, by editing this one file. In fact, pretty much anything goes – if we wanted to, we could hav e different layouts for each of the 10 banks, or leave some banks unassigned, for use with guitar effects, etc. To help with layout planning, an editable PDF template for the FCB1010 is included with the source code on the Support Files page. Okay, so now it’s time to assemble the code. Since we’re essentially emulating the APC40 here (yes, I admit that I was wrong in Part 2; APC40 emulation is not so crazy after all), we h ave a choice between starting with the APC scripts and customizing, or building a new set of scripts which have similar functionality. Since we won’t be supporting shifted operations in our script (for the FCB1010 this would require operation with two feet – difficult to do in an upright position), we will need to make significant changes to the APC scripts. Starting from scratch is definitely an option worth considering. On the other hand, the APC40 script will make for a good roadmap, and while we’re at it, we can include some of the special features of the APC40_22 script from Part 3 here as well. The structure will be fairly simple. We’ll have an __init__.py module (to identify the directory as a python package), a main module (called FCB1020.py ), a MIDI_map.py constants file, and several “special” Framework component override modules. Here’s the file list (compete source code is available on the Support Files page): __init__.py FCB1020.py MIDI_Map.py
SpecialChannelStripComponent.py SpecialMixerComponent.py SpecialSessionComponent.py SpecialTransportComponent.py SpecialViewControllerComponent.py SpecialZoomingComponent.py We won’t go into detail on the Special components, since that topic was covered in Part 3. The main module follows the structure outlined in Part 1, but here's a quick overview. We start with the imports, and then define the combination mode static method (as discussed above):
import Live from _Framework.ControlSurface import ControlSurface from _Framework.InputControlEl ement import * from _Framework.SliderElement import SliderElement from _Framework.ButtonElement import ButtonElement from _Framework.ButtonMatrixEl ement import ButtonMatrixElement from _Framework.ChannelStripCo mponent import ChannelStripComponent from _Framework.DeviceComponen t import DeviceComponent from _Framework.ControlSurface Component import ControlSurfaceComponent from _Framework.SessionZooming Component import SessionZoomingComponent from SpecialMixerComponent import SpecialMixerComponent from SpecialTransportComponent import SpecialTransportComponent from SpecialSessionComponent import SpecialSessionComponent from SpecialZoomingComponent import SpecialZoomingComponent from SpecialViewControllerComponent import DetailViewControllerComponent from MIDI_Map import * class FCB1020(ControlSurface): __doc__ = " Script for FCB1010 in APC emulation mode " _active_instances = [] def _combine_active_instances(): track_offset = 0 scene_offset = 0 for instance in FCB1020._active_instances: instance._activate_combination_mode(track_offset, scene_offset) track_offset += instance._session.width() _combine_active_instances = staticmethod(_combine_active_instances) Next we have our init method, where we instantiate our ControlSurface component and call the various setup methods. We setup the session, then setup the mixer, then assign the mixer to the session, to keep them in sync. The disconnect method follows, where we provide some cleanup for when the control surface is disconnected: def __init__(self, c_instance): ControlSurface.__init__(self, c_instance) self.set_suppress_rebuild_requests(True) self._note_map = [] self._ctrl_map = [] self._load_MIDI_map() self._session = None self._session_zoom = None self._mixer = None self._setup_session_control() self._setup_mixer_control()
self._session.set_mixer(self._mixer) self._setup_device_and_transport_control() self.set_suppress_rebuild_requests(False) self._pads = [] self._load_pad_translations() self._do_combine()
def disconnect(self): self._note_map = None self._ctrl_map = None self._pads = None self._do_uncombine() self._shift_button = None self._session = None self._session_zoom = None self._mixer = None ControlSurface.disconnect(self) The balance of the combination mode methods are next: def _do_combine(self): if self not in FCB1020._active_instances: FCB1020._active_instances.append(self) FCB1020._combine_active_instances() def _do_uncombine(self): if ((self in FCB1020._active_instances) and FCB1020._active_instances.remove(self)): self._session.unlink() FCB1020._combine_active_instances() def _activate_combination_mode(self, track_offset, scene_offset): if TRACK_OFFSET != -1: track_offset = TRACK_OFFSET if SCENE_OFFSET != -1: scene_offset = SCENE_OFFSET self._session.link_with_track_offset(track_offset, scene_offset) The session setup is based on Framework SessionComponent methods, with SessionZoomingComponent navigation thrown in for good measure: def _setup_session_control(self): is_momentary = True self._session = SpecialSessionComponent(8, 5) self._session.name = 'Session_Control' self._session.set_track_bank_buttons(self._note_map[SESSIONRIGHT], self._note_map[SESSIONLEFT]) self._session.set_scene_bank_buttons(self._note_map[SESSIONDOWN], self._note_map[SESSIONUP]) self._session.set_select_buttons(self._note_map[SCENEDN], self._note_map[SCENEUP]) self._scene_launch_buttons = [self._note_map[SCENELAUNCH[index]] for index in range(5) ] self._track_stop_buttons = [self._note_map[TRACKSTOP[index]] for index in range(8) ]
self._session.set_stop_all_clips_button(self._note_map[STOPALLCLIPS]) self._session.set_stop_track_clip_buttons(tuple(self._track_stop_buttons)) self._session.set_stop_track_clip_value(2) self._session.selected_scene().name = 'Selected_Scene' self._session.selected_scene().set_launch_button(self._note_map[SELSCENELAUNC H]) self._session.set_slot_launch_button(self._note_map[SELCLIPLAUNCH]) for scene_index in range(5): scene = self._session.scene(scene_index) scene.name = 'Scene_' + str(scene_index) button_row = [] scene.set_launch_button(self._scene_launch_buttons[scene_index]) scene.set_triggered_value(2) for track_index in range(8): button = self._note_map[CLIPNOTEMAP[scene_index][track_index]] button_row.append(button) clip_slot = scene.clip_slot(track_index) clip_slot.name = str(track_index) + '_Clip_Slot_' + str(scene_index) clip_slot.set_launch_button(button) self._session_zoom = SpecialZoomingComponent(self._session) self._session_zoom.name = 'Session_Overview' self._session_zoom.set_nav_buttons(self._note_map[ZOOMUP], self._note_map[ZOOMDOWN], self._note_map[ZOOMLEFT], self._note_map[ZOOMRIGHT])
Mixer, device, and transport setup methods are similar. def _setup_mixer_control(self): is_momentary = True self._mixer = SpecialMixerComponent(8) self._mixer.name = 'Mixer' self._mixer.master_strip().name = 'Master_Channel_Strip' self._mixer.master_strip().set_select_button(self._note_map[MASTERSEL]) self._mixer.selected_strip().name = 'Selected_Channel_Strip' self._mixer.set_select_buttons(self._note_map[TRACKRIGHT], self._note_map[TRACKLEFT]) self._mixer.set_crossfader_control(self._ctrl_map[CROSSFADER]) self._mixer.set_prehear_volume_control(self._ctrl_map[CUELEVEL]) self._mixer.master_strip().set_volume_control(self._ctrl_map[MASTERVOLUME]) for track in range(8): strip = self._mixer.channel_strip(track) strip.name = 'Channel_Strip_' + str(track) strip.set_arm_button(self._note_map[TRACKREC[track]]) strip.set_solo_button(self._note_map[TRACKSOLO[track]]) strip.set_mute_button(self._note_map[TRACKMUTE[track]]) strip.set_select_button(self._note_map[TRACKSEL[track]]) strip.set_volume_control(self._ctrl_map[TRACKVOL[track]]) strip.set_pan_control(self._ctrl_map[TRACKPAN[track]]) strip.set_send_controls((self._ctrl_map[TRACKSENDA[track]], self._ctrl_map[TRACKSENDB[track]], self._ctrl_map[TRACKSENDC[track]]))
strip.set_invert_mute_feedback(True)
def _setup_device_and_transport_control(self): is_momentary = True self._device = DeviceComponent() self._device.name = 'Device_Component' device_bank_buttons = [] device_param_controls = [] for index in range(8): device_param_controls.append(self._ctrl_map[PARAMCONTROL[index]]) device_bank_buttons.append(self._note_map[DEVICEBANK[index]]) if None not in device_bank_buttons: self._device.set_bank_buttons(tuple(device_bank_buttons)) self._device.set_parameter_controls(tuple(device_param_controls)) self._device.set_on_off_button(self._note_map[DEVICEONOFF]) self._device.set_bank_nav_buttons(self._note_map[DEVICEBANKNAVLEFT], self._note_map[DEVICEBANKNAVRIGHT]) self._device.set_lock_button(self._note_map[DEVICELOCK]) self.set_device_component(self._device) detail_view_toggler = DetailViewControllerComponent() detail_view_toggler.name = 'Detail_View_Control' detail_view_toggler.set_device_clip_toggle_button(self._note_map[CLIPTRACKVIE W]) detail_view_toggler.set_detail_toggle_button(self._note_map[DETAILVIEW]) detail_view_toggler.set_device_nav_buttons(self._note_map[DEVICENAVLEFT], self._note_map[DEVICENAVRIGHT] ) transport = SpecialTransportComponent() transport.name = 'Transport' transport.set_play_button(self._note_map[PLAY]) transport.set_stop_button(self._note_map[STOP]) transport.set_record_button(self._note_map[REC]) transport.set_nudge_buttons(self._note_map[NUDGEUP], self._note_map[NUDGEDOWN]) transport.set_undo_button(self._note_map[UNDO]) transport.set_redo_button(self._note_map[REDO]) transport.set_tap_tempo_button(self._note_map[TAPTEMPO]) transport.set_quant_toggle_button(self._note_map[RECQUANT]) transport.set_overdub_button(self._note_map[OVERDUB]) transport.set_metronome_button(self._note_map[METRONOME]) transport.set_tempo_control(self._ctrl_map[TEMPOCONTROL]) transport.set_loop_button(self._note_map[LOOP]) transport.set_seek_buttons(self._note_map[SEEKFWD], self._note_map[SEEKRWD]) transport.set_punch_buttons(self._note_map[PUNCHIN], self._note_map[PUNCHOUT]) We’ve also included a DetailViewComponent above, which communicates session view changes via the Live API. Next is _on_selected_track_changed , a ControlSurface class method override, which keeps the selected track’s device in focus. And for drum rack note mapping, we’ve included a _load_pad_translationsmethod, which adds x and y offsets to the Drum Rack note and channel assignments, which are set in
the MIDI_map.py file. This allows us to pass the translations array as an argument to the ControlSurface set_pad_translations method in the expected format. def _on_selected_track_changed(self): ControlSurface._on_selected_track_changed(self) track = self.song().view.selected_track device_to_select = track.view.selected_device if device_to_select == None and len(track.devices) > 0: device_to_select = track.devices[0] if device_to_select != None: self.song().view.select_device(device_to_select) self._device_component.set_device(device_to_select) def _load_pad_translations(self): if -1 not in DRUM_PADS: pad = [] for row in range(4): for col in range(4): pad = (col, row, DRUM_PADS[row*4 + col], PADCHANNEL,) self._pads.append(pad) self.set_pad_translations(tuple(self._pads)) Finally, we have _load_MIDI_map. Here, we create a list of ButtonElements and a list of SliderElements . When we make mapping assignments in our MIDI_map.py file, we are actually indexing objects from these lists. By instantiating the ButtonElements and SliderElements as independent objects, we limit the risk of duplicate MIDI assignments, which would prevent our script from loading. Any particular MIDI note/channel message from a control surface can only be assigned to a single InputControlElement (such as a button or slider), however, an InputControlElement can be used more than once, with different components. This setup also allows us to append None to the end of each list, so that null assignments can be specified in the MIDI_map file, by using -1 in place of a note number (in python, [-1] corresponds to the last element of a list). def _load_MIDI_map(self): is_momentary = True for note in range(128): button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, NOTECHANNEL, note) button.name = 'Note_' + str(note) self._note_map.append(button) self._note_map.append(None) #add None to the end of the list, selectable with [-1] for ctrl in range(128): control = SliderElement(MIDI_CC_TYPE, CTRLCHANNEL, ctrl) control.name = 'Ctrl_' + str(ctrl) self._ctrl_map.append(control) self._ctrl_map.append(None) Now, speaking of MIDI assignments, since all of our mappings are editable, and grouped in a separate file, couldn’t we use our script with just about any control surface, and not only the FCB1010? Yes, indeed we could. Generic APC Emulation
Our new FCB10120 script can be used as a generic APC emulator, since it merely maps MIDI Note and CC input to specific _Framework component functions, mimicking the APC script setup. In fact, none of this is very different from the User script mechanism provided by Ableton - although our script has a few extra
features that the User script does not support, including Session Highlighting (aka “red box”), and the ability to work in combination mode, with an A PC40, or with another instance of itself, or with any other controller which supports combination mode.
Some setup is required, however, to accommodate alternate controller configurations. These configurations could be alternate configurations for the same control surface, or alternate configurations for different control surfaces. Probably the simplest way of setting up an alternate configuration, is to create one or more copies of the FCB1020 script folder, modify the assignments in the MIDI_map.py file as required, and then re-name the directory to suit. The new folder will be selectable by name from Live’s control surface drop -down list, the next time Live is started. This way, one could have, say, FCB1020_device_mode and FCB1020_transport_mode as separate configurations, listed one above the other in the control surface drop-down. Note however , that one should avoid leading unders cores in folder name, unless a folder is intended to be hidden. Another way to accommodate alternate setups would be to reprogram the control surface itself – where this is possible - to match the note and CC mappings found in the MIDI_map.py file. Depending on the control surface, this could be done manually, with stand-alone software, or by using Live’s “dump” button from the preferences dialog (in fact, a sysex file for the FCB1010 is included with the sup port files package which accompanies this article, for this purpose). Of course, our script can also be used as a generic APC emulator for multiple controllers at the same time . This can be done a number of ways, including: 1) Daisy-chain several control surfaces using MIDI Thru ports; 2) Load the script multiple times, using multiple slots; 3) Create multiple copies of the script folder, r ename to suit, and load into different slots. For multiple control surfaces which use different MIDI channels, separate instances of the script would need to be loaded, from separate folders, with the channel assignments in the MIDI_maps.py modified to suit in each folder. And getting back to our origi nal design setup, we can see that the FCB1010 and the APC40 now work w ell together in Combination Mode, and the FCB1010 is able to control of most of the APC’s functions – within one session highlight area, and without loss of focus. We have included a good deal of flexibility in our script too, so we can easily modify the various bank layouts to suit our needs, as they develop and change. Conclusion
In this new era of multi-touch controllers, it’s nice to know that a sturdy old workhorse like the FCB1010 still has a place in our arsenal of control surfaces - and that i t works well in combination with the soon -to-be-aclassic and not-yet- obsolete APC40. As for MIDI remote scripts, they’re still at the heart of all control surface communications with the Live API - and the _Framework classes have been holding their own for quite a while now, with interesting new methods being added from time to time. Hopefully, this series of articles has been useful, and will encourage others to share their findings with the Live community. Happy scripting. Hanz Petrov September 7, 2010 hanz.petrov at gmail.com
Introduction to the Framework Classes Part 2 Background In this post, we’ll have a look at the differences between Live 7 and Live 8 remote scripts, get the Max for Live point-of-view on control surfaces, take a detailed look at the newest APC40 (and APC20) scripts – and demonstrate a few APC script hacks along the way. If you’re new to MIDI remote scripts, you might want to have a look at Part 1 of the Introduction to the Framework Classes before coming back here for Part 2. Keeping up with recent changes
As discussed previously, most of what we know about MIDI remote scripting has been based on exploring decompiled Python pyc files. The Live 7 remote scripts are Python 2.2 files, and hav e proven to be relatively easy to decompile. Live 8’s integration of Python 2.5, on the other hand, presents a new challenge. At present, there is no reliable, freely accessible method for decompiling 2.5 pyc files. It i s possible, however, to get a good sense of the latest changes made to the MIDI remote scripts using the tools at hand. Unpyc is one such tool, and unpyc can decompile python 2.5 files - but only up to a point. In most cases, it will only produce partial source code, but at least it lets us know where it is having trouble. It can, however, disassemble 2.5 files without fail. When we’re armed with a partial decompile, and a complete disassembly, it is possible to reconstruct working script source code - although the process is tedious at the best of times. But even without reconstructing complete sources, Unpyc allows us to take a peek behind the scenes and understand the nature of the changes implemented with the most recent MIDI remote scripts. As an example, here is the mixer setup method from the APC40.py script - Live 8.1.1 version: def _setup_mixer_control(self): is_momentary = True mixer = SpecialMixerComponent(8) mixer.name = 'Mixer' mixer.master_strip().name = 'Master_Channel_Strip' mixer.selected_strip().name = 'Selected_Channel_Strip' for track in range(8): strip = mixer.channel_strip(track) strip.name = 'Channel_Strip_' + str(track) volume_control = SliderElement(MIDI_CC_TYPE, track, 7) arm_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 48) solo_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 49) mute_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 50) select_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 51) volume_control.name = str(track) + '_Volume_Control' arm_button.name = str(track) + '_Arm_Button' solo_button.name = str(track) + '_Solo_Button' mute_button.name = str(track) + '_Mute_Button' select_button.name = str(track) + '_Select_Button' strip.set_volume_control(volume_control) strip.set_arm_button(arm_button) strip.set_solo_button(solo_button) strip.set_mute_button(mute_button) strip.set_select_button(select_button) strip.set_shift_button(self._shift_button) strip.set_invert_mute_feedback(True) crossfader = SliderElement(MIDI_CC_TYPE, 0, 15)
master_volume_control = SliderElement(MIDI_CC_TYPE, 0, 14) master_select_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0,
80) prehear_control = EncoderElement(MIDI_CC_TYPE, 0, 47, Live.MidiMap.MapMode.relative_two_compliment) crossfader.name = 'Crossfader' master_volume_control.name = 'Master_Volume_Control' master_select_button.name = 'Master_Select_Button' prehear_control.name = 'Prehear_Volume_Control' mixer.set_crossfader_control(crossfader) mixer.set_prehear_volume_control(prehear_control) mixer.master_strip().set_volume_control(master_volume_control) mixer.master_strip().set_select_button(master_select_button) return mixer
Compare the above with the equivalent code from the 7.0.18 version: def _setup_mixer_control(self): is_momentary = True mixer = MixerComponent(8) for track in range(8): strip = mixer.channel_strip(track) strip.set_volume_control(SliderElement(MIDI_CC_TYPE, track, 7)) strip.set_arm_button(ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 48)) strip.set_solo_button(ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 49)) strip.set_mute_button(ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 50)) strip.set_select_button(ButtonElement(is_momentary, MIDI_NOTE_TYPE, track, 51)) strip.set_shift_button(self._shift_button) strip.set_invert_mute_feedback(True) mixer.set_crossfader_control(SliderElement(MIDI_CC_TYPE, 0, 15)) mixer.set_prehear_volume_control(EncoderElement(MIDI_CC_TYPE, 0, 47, Live.MidiMap.MapMode.relative_two_compliment)) mixer.master_strip().set_volume_control(SliderElement(MIDI_CC_TYPE, 0, 14)) mixer.master_strip().set_select_button(ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 80)) return mixer As we can see, the main difference between the Live 7.0.18 code and the Live 8.1.1 code is that in the new script, name attributes have been assigned to most of the components and elements. So who needs names? Max for Live needs names. Max for Live – keeping up with Cycling ‘74
Max for Live requires Live 8.1 or higher, and, accordingly, new Live 8 versions include Max-compatible MIDI remote scripts. The name attributes assigned to the python objects and methods allow Max for Live to see and access python methods and objects more easi ly (objects including control surfaces, components, and control elements). This can be verified with the help of Max for Live’s LiveAPI resource patches (M4L.api.SelectComponent, M4L.api.SelectControlSurface, M4L.api.SelectControl, etc.). Before we demonstrate, however, let’s have a look at how Control Surfaces fit into the world of Max’s Live Object Model (LOM).
The three main root objects in the Live Object Model are known as live_app (Application), live_set (Song), and control_surfaces (Control Surface). Cycling ‘74 provides somewhat detailed documentation for the first two, however, the last one seems to have been left out - intentionally, no doubt. Based on the LOM diagram , we can see that the Control Surfaces root object includes classes for components and controls. These m ap directly to python Framework modules (modules with name s like ControlSurface, TransportComponent, SessionComponent , ButtonElement , etc.). Now, although documentation which explains this is almost non-exi stent, it turns out that the python methods and objects of the Framework classes are both v isible and accessible from Max for L ive. The remote script methods appear to Max as functions – functions which can be called using the syntax and arguments defined in the Python scripts. It is now clear that in order to gain a proper understanding of how to manipulate more complicated Control Surfaces, a study of the python remote scripts is essential - because that's where the Control Surface functions originate. We'll be demonstrating this link between Max for Live and the python scripts, but before we do, let’s take a peek under the hood of what has proven to be a very popular Live controller the APC40 (now almost a year old). The APC40 – under the hood
The latest Live 7 versions include MIDI remote scripts for the APC40, and, of course, Live 8.1 and higher also support the APC40. As mentioned above, the Live 8.1 versions of the APC40 scripts show slight differences generally, name attributes have been added to most of the methods and objects. We’ll base our investigation here on the 8.1.1 scripts, in an effort to stay somewhat current. There are 11 files in the APC40 MIDI remote scripts directory: __init__.pyc APC40.pyc DetailViewControllerComponent.pyc EncoderMixerModeSelectorComponent.pyc PedaledSessionComponent.pyc ShiftableDeviceComponent.pyc ShiftableTranslatorComponent.pyc ShiftableTransportComponent.pyc SpecialChannelStripComponent.pyc SpecialMixerComponent.pyc RingedEncoderElement.pyc
The __init__.py script is rather uninteresting, as it is with most scripts: import Live from APC40 import APC40 def create_instance(c_instance): """ Creates and returns the APC40 script """ return APC40(c_instance) This is a standard init, as shown in Part 1 of the Introduction to Remote Scripts. Now, the script files here with the longish names are special classes, which inherit from Framework modules, but add custom functionality. What they do (and the name of the Framework classes they inherit from) is described in the Docstrings of the scripts themselves: class DetailViewControllerComponent(ControlSurfaceComponent): ' Component that can toggle the device chain- and clip view of the selected track ' class EncoderMixerModeSelectorComponent(ModeSelectorComponent): ' Class that reassigns encoders on the AxiomPro to different mixer functions '
class PedaledSessionComponent(SessionComponent): ' Special SessionComponent with a button (pedal) to fire the selected clip slot ' class RingedEncoderElement(EncoderElement): ' Class representing a continuous control on the controller enclosed with an LED ring ' class ShiftableDeviceComponent(DeviceComponent): ' DeviceComponent that only uses bank buttons if a shift button is pressed ' class ShiftableTranslatorComponent(ChannelTranslationSelector): ' Class that translates the channel of some buttons as long as a shift button is held ' class ShiftableTransportComponent(TransportComponent): ' TransportComponent that only uses certain buttons if a shift button is pressed ' It is interesting to note that the EncoderMixerModeSelectorComponent module appears to have been recycled from the AxiomPro script. And, for anyone in terested, the rest of the python code can be examined here. The most interesting module of the l ot by far, is APC40.py - which is where most of the action is. This file begins with the imports: import Live from _Framework.ControlSurface import ControlSurface from _Framework.InputControlEl ement import * from _Framework.SliderElement import SliderElement from _Framework.ButtonElement import ButtonElement from _Framework.EncoderElement import EncoderElement from _Framework.ButtonMatrixEl ement import ButtonMatrixElement from _Framework.MixerComponent import MixerComponent from _Framework.ClipSlotCompon ent import ClipSlotComponent from _Framework.ChannelStripCo mponent import ChannelStripComponent from _Framework.SceneComponent import SceneComponent from _Framework.SessionZooming Component import SessionZoomingComponent from _Framework.ChannelTransla tionSelector import ChannelTranslationSelector from EncoderMixerModeSelectorComponent import EncoderMixerModeSelectorComponent from RingedEncoderElement import RingedEncoderElement from DetailViewControllerComponent import DetailViewControllerComponent from ShiftableDeviceComponent import ShiftableDeviceComponent from ShiftableTransportComponent import ShiftableTransportComponent from ShiftableTranslatorComponent import ShiftableTranslatorComponent from PedaledSessionComponent import PedaledSessionComponent from SpecialMixerComponent import SpecialMixerComponent As expected, in addition to the Live import (which provides direct access to the Live API), and the special modules listed previously, all of the other imports are _Framework modules. Again, see Part 1 for more detail. Next are the constants, which are used in the APC40 sysex exchange (more on this later): SYSEX_INQUIRY = (240, 126, 0, 6, 1, 247) MANUFACTURER_ID = 71 PRODUCT_MODEL_ID = 115 APPLICTION_ID = 65
CONFIGURATION_ID = 1
Then, after the name and docstring, we have the obligatory __init__ method. The APC40 __init__ looks like this: def __init__(self, c_instance): ControlSurface.__init__(self, c_instance) self.set_suppress_rebuild_requests(True) self._suppress_session_highlight = True is_momentary = True self._shift_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 98) self._shift_button.name = 'Shift_Button' self._suggested_input_port = 'Akai APC40' self._suggested_output_port = 'Akai APC40' session = self._setup_session_control() mixer = self._setup_mixer_control() self._setup_device_and_transport_control() self._setup_global_control(mixer) session.set_mixer(mixer) for component in self.components: component.set_enabled(False) self.set_suppress_rebuild_requests(False) self._device_id = 0 self._common_channel = 0 self._dongle_challenge = (Live.Application.get_random_int(0, 2000000), Live.Application.get_random_int(2000001, 4000000)) As we can see, standard Framework-based scripting is used to create a session object, a mixer, device and transport components, and global controls, and then to assign the mixer to the session. There’s nothing very mysterious here – except perhaps _dongle_challenge. And - you may be wondering - where does the infamous “secret handshake” live? Why, in handle_sysex of course. The Secret Handshake – not so secret anymore
Within days of the APC40 hitting retail shelves, it was discovered that the secret handshake is based on a sysex exchange. But how does it work exactly, and what is it hiding? It’s not hiding anything that can’t b e done with basic Framework scripting (as we saw in Part 1), and it works by sending a “dongle challenge” sysex string, then looking for a correct response from the controller. If the response from the controller matches the expected response (i.e. the handshake succeeds), then all of the controls on the controller are enabled and the session highlight (aka “red box”) is turned on. Here’s part of the handle_sysex method, in native python: def handle_sysex(self, midi_bytes): if ((midi_bytes[3] == 6) and (midi_bytes[4] == 2)): assert (midi_bytes[5] == MANUFACTURER_ID) assert (midi_bytes[6] == PRODUCT_MODEL_ID) version_bytes = midi_bytes[9:13] self._device_id = midi_bytes[13] self._send_midi((240, MANUFACTURER_ID, self._device_id, PRODUCT_MODEL_ID, 96, 0, 4,
APPLICTION_ID, self.application().get_major_version(), self.application().get_minor_version(), self.application().get_bugfix_version(), 247)) challenge1 = [0,0,0,0,0,0,0,0] challenge2 = [0,0,0,0,0,0,0,0] #... dongle_message = ((((240, MANUFACTURER_ID, self._device_id, PRODUCT_MODEL_ID, 80, 0, 16) + tuple(challenge1)) + tuple(challenge2)) + (247)) self._send_midi(dongle_message) message = ((('APC40: Got response from controller, version ' + str(((version_bytes[0] << 4) + version_bytes[1]))) + '.') + str(((version_bytes[2] << 4) + version_bytes[3]))) self.log_message(message) elif (midi_bytes[4] == 81): assert (midi_bytes[1] == MANUFACTURER_ID) assert (midi_bytes[2] == self._device_id) assert (midi_bytes[3] == PRODUCT_MODEL_ID) assert (midi_bytes[5] == 0) assert (midi_bytes[6] == 16) response = [long(0), long(0)] #... expected_response = Live.Application.encrypt_challenge(self._dongle_challenge[0], self._dongle_challenge[1]) if ((long(expected_response[0]) == response[0]) and (long(expected_response[1]) == response[1])): self._suppress_session_highlight = False for component in self.components: component.set_enabled(True) self._on_selected_track_changed()
The above sysex usage matches that described in the Akai APC40 Communications Protocol document. Well, the standard MMC Device Enquiry and response parts do anyway – the dongle part is not documented. As we can see, some of this exchange involves setting the APC40 into “Ableton Mode” and identifying the host application to the APC40 as Live – complete with major, minor, and bugfix version info. Although the APC40 handshake is effective at discouraging casual emulation, it is not clear what exactly is being protected here, since any script can make of use the Framework SessionComponent module (or the Live API) to get the infamous “red box” to display. On the other hand, who in their right mind would want to emulate a hard-wired non-programmable MIDI controller with an 8x5 grid of LED buttons, 16 rotary controllers, a cross-fader, and 9 sliders – unless they’re someone who already owns an APC40?! I suspect that the majority of Monome owners probably wouldn’t be interested in using their high -end boutique hardware to emulate a mass-market controller like the APC40, and besides, they’ve already got a wealth of opensource software applications and scripts to play with. So the real mystery is: why the dongle? In any event, bypassing the handshake is simply a matter of overriding the handle_sysex method. Other than for Mode initialization, sysex is not an important part of the APC40 scripts.
Now, for a change of pace, let’s have a quick look at how we can manipulate the APC40’s LEDs using a remote script. We’ll set up a little light show with some python code, and then call it up from Max. APC40 Lights & Magic
As described in the APC40 Communications Protocol document, the various LEDs on the A PC40 (around 380 of them according to Akai - and hence the need for a separate power supply) can be manipulated via MIDI messages sent to the controller. No sysex voodoo here – simple note on and note off commands is all it takes. The LEDs are turned on with MIDI note-on messages. The first byte of the message is the note-on part, with the MIDI channel bits used to identify the track number (for those LEDs which are associated with tracks). Individual LEDs are identified using the second byte (the note number), and the third byte is used to set the colour and state of the LED. The APC40 note map is a useful reference here.
The Communications Protocol document lists the following possible colours and states for the clip launch LEDs: 0=off, 1=green, 2=green blink, 3=red, 4=red blink, 5=yellow, 6=yellow blink, 7127=green
In the _setup_session_control method of the APC40 python script, these are assigned as values: clip_slot.set_started_value(1) clip_slot.set_triggered_to_play_value(2) clip_slot.set_recording_value(3) clip_slot.set_triggered_to_record_value(4) clip_slot.set_stopped_value(5)
The values in the python scr ipt match the colours and states listed in the Communications Protocol document, although only 5 are assigned above. If we wanted to change the 8x5 grid colour assignments (if we had colour vision deficiency, for example), we’d need to override this part of the script. Now, based on this information, we’ll set up a random pattern of colours - using the Live API to generate the random values – and then get the colours to scr oll down the rows of the matrix. Before we can call our new
functions, however, we’ll need a MIDI remote script to put them in. Although we could add the new code straight into the APC40 script (by modifying the source code), instead, let’s create a new script which inherits from the APC40 class. We’ll cal l our new control surface script APC40plus1. Here’s the new _init__.py code for our new script:
from APC40plus1 import APC40plus1 def create_instance(c_instance): return APC40plus1(c_instance) And here’s the code for our new APC40plus1 class, complete with lightshow methods:
# http://remotescripts.blogspot.com from APC40.APC40 import * class APC40plus1(APC40): __module__ = __name__ __doc__ = ' Main class derived from APC40 ' def __init__(self, c_instance): APC40.__init__(self, c_instance) self.show_message("APC40plus1 script loaded") self.light_loop() def light_loop(self): #self.name = 'light_loop' for index in range (4, 105, 4): #start lights in 4 ticks; end after 104; step in 4 tick increments self.schedule_message(index, self.lights_on) #turn lights on for index in range (108, 157, 4): #start turning off after 108 ticks; end after 156; step in 4 tick increments self.schedule_message(index, self.lights_off) #turn lights off self.schedule_message(156, self.refresh_state) #refresh the controller to turn clip lights back on def lights_on(self): for col_num in range (8): #load random colour numbers into the buffer row (row 0) colour = Live.Application.get_random_int(0, 10) #0=off, 1=green, 2=green blink, 3=red, 4=red blink, 5=yellow, 6=yellow blink, 7-127=green if colour % 2 == 0 or colour > 6: #filter out the blinking lights (even numbers) and skew towards having more "off" lights colour = 0 list_of_rows[0][col_num] = colour #load the buffer row self.load_leds() def lights_off(self): for col_num in range (8): #step through 8 columns/tracks/channels list_of_rows[0][col_num] = 0 #set to zero (lights off) self.load_leds() def load_leds(self): for row_num in range (6, 0, -1): #the zero row is a buffer, which gets loaded with a random sequence of colours note = 52 + row_num #set MIDI notes to send to APC, starting at 53, which is the first scene_launch button
if row_num == 6: #the clip_stop row is out of sequence with the grid note = 52 #note number for clip_stop row for col_num in range (8): #8 columns/tracks/channels list_of_rows[row_num][col_num] = list_of_rows[row_num1][col_num] #load each slot from the preceding row status_byte = col_num #set channel part of status_byte status_byte += 144 #add note_on to channel number self._send_midi((status_byte, note, list_of_rows[row_num][col_num])) #for APC LEDs, send (status_byte, note, colour) list_of_rows = [[0]*8 for index in range(7)] #create an 8 x 7 array of zeros; 8 tracks x (1 buffer row + 5 scene rows + 1 clip stop row)
With these two files saved to a new MIDI remote scripts folder, we can select our new controller script in the MIDI preferences drop-down. This will force Live to compile and run the new script. If the “red box” doesn’t show up, we know that something is wrong, and we can check the Live log file for errors, and trouble-shoot from there. We’ve set up our light show to run on initialization, so it should run immediately, but what we really wanted to demonstrate is that the our functions can be called from Max for Live. For this, we’ll create a simple Max patch which uses the M4L.api.SelectControlSurface resource patch to get a path to our new function, s o that we can bang it with the function call. We send a call light_loop message to the control script, which in turn calls lightshow_on to turns the lights on, and lightshow_off to turn the lights back off - and resets the control surface, so that the LEDs reflect session view state.
And here's the result:
Well, although that was a neat diversion, let’s try to do something more useful here – we’ll re-assign the Metronome button to act as a Device Lock button. We’ll do this using our same APC40plus1 script, together with some method overrides (and without the help of Max for Live this time). Device Lock – why isn’t this feature standard?
The Framework TransportComponent class contains both of the methods which interest us here: set_metronome_button and set_device_lock_button . These are inherited by the APC40 class, and can be used to change the button assignments. In order to change one for the other, we need to override the APC40 script method where they are normally assigned. This happens in the _setup_device_and_transport_control section of code. Before we override the method, however, we’ll need to do some basic setup.
First, we instantiate an APC40 ControlSurface object, then we initialize using the APC40’s __init__ method, and finally we override the _setup_device_and_transport_control method, which is w here we assign the physical metronome button to act as a dev ice lock button:
# http://remotescripts.blogspot.com from APC40.APC40 import * class APC40plus1(APC40): __module__ = __name__ __doc__ = ' Main class derived from APC40 ' def __init__(self, c_instance): APC40.__init__(self, c_instance) self.show_message("APC40plus1 script loaded") def _setup_device_and_transport_control(self): #overriden so that we can to reassign the metronome button to device lock is_momentary = True device_bank_buttons = [] device_param_controls = [] bank_button_labels = ('Clip_Track_Button', 'Device_On_Off_Button', 'Previous_Device_Button', 'Next_Device_Button', 'Detail_View_Button', 'Rec_Quantization_Button', 'Midi_Overdub_Button', 'Device_Lock_Button') for index in range(8): device_bank_buttons.append(ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 58 + index)) device_bank_buttons[-1].name = bank_button_labels[index] ring_mode_button = ButtonElement(not is_momentary, MIDI_CC_TYPE, 0, 24 + index) ringed_encoder = RingedEncoderElement(MIDI_CC_TYPE, 0, 16 + index, Live.MidiMap.MapMode.absolute) ringed_encoder.set_ring_mode_button(ring_mode_button) ringed_encoder.name = 'Device_Control_' + str(index) ring_mode_button.name = ringed_encoder.name + '_Ring_Mode_Button' device_param_controls.append(ringed_encoder) device = ShiftableDeviceComponent() device.name = 'Device_Component' device.set_bank_buttons(tuple(device_bank_buttons)) device.set_shift_button(self._shift_button) device.set_parameter_controls(tuple(device_param_controls)) device.set_on_off_button(device_bank_buttons[1]) device.set_lock_button(device_bank_buttons[7]) #assign device lock to bank_button 8 (in place of metronome)... self.set_device_component(device) detail_view_toggler = DetailViewControllerComponent() detail_view_toggler.name = 'Detail_View_Control' detail_view_toggler.set_shift_button(self._shift_button) detail_view_toggler.set_device_clip_toggle_button(device_bank_buttons[0]) detail_view_toggler.set_detail_toggle_button(device_bank_buttons[4]) detail_view_toggler.set_device_nav_buttons(device_bank_buttons[2], device_bank_buttons[3]) transport = ShiftableTransportComponent() transport.name = 'Transport' play_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 91) stop_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 92)
record_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 93) nudge_up_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 100) nudge_down_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0,
101) tap_tempo_button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, 0, 99) play_button.name = 'Play_Button' stop_button.name = 'Stop_Button' record_button.name = 'Record_Button' nudge_up_button.name = 'Nudge_Up_Button' nudge_down_button.name = 'Nudge_Down_Button' tap_tempo_button.name = 'Tap_Tempo_Button' transport.set_shift_button(self._shift_button) transport.set_play_button(play_button) transport.set_stop_button(stop_button) transport.set_record_button(record_button) transport.set_nudge_buttons(nudge_up_button, nudge_down_button) transport.set_tap_tempo_button(tap_tempo_button) transport.set_quant_toggle_button(device_bank_buttons[5]) transport.set_overdub_button(device_bank_buttons[6]) #transport.set_metronome_button(device_bank_buttons[7]) #using this button for lock to device instead... bank_button_translator = ShiftableTranslatorComponent() bank_button_translator.set_controls_to_translate(tuple(device_bank_buttons)) bank_button_translator.set_shift_button(self._shift_button)
Now, we save our new APC40plus1 script into its MIDI Remote Scripts directory, fire up Live, and select APC40plus1 from the MIDI Control Surfaces drop-down. Voilà, the Metronome button is now a Devi ce Lock button (sorry, no video - but trust me - it does work). The python code for this mod (together with the lightshow) can be downloaded here. Now, although we’ve made functional changes without modifying the original APC40 scripts, we’re still dependent on those original scripts, because we inherit methods from them. This means that we’ll need to watch out for MIDI remote script changes in new versions of Live, since they might break our new script. So why don’t we get a head start by checking out compatibility with 8.1.3 RC-1? Live 8.1.3 – subtle changes
As Live 8.1.3 enters the Release Candidate phase, we can take a sneak peek at the close-to-final MIDI remote scripts included with the beta release. It turns out that not much has changed here. The Framework classes are essentially the same, and support for one or two new control surfaces has been added – most notably the APC20 and Serato controllers. We’ll leave the Serato scripts for a future investigation (they look fascinating by the way), and take a peek under the hood of the APC20 scripts instead. APC20 – the APC40’s little brother
The APC20 is basically an APC 40 minus the cross-fader, rotary controllers, and right hand buttons. To maintain basic functionality with fewer buttons, some of the buttons on the left hand side are now dualpurpose, as described in the APC20 Quickstart Guide. For example, the APC40’s Stop All Clips button has become the Shift button on the A PC20. By holding down this button and selecting one of the Record buttons, the APC20 sliders can be assigned to Volume, Pan, Send A , Send B, Send C, User 1, User 2, or User 3. One new APC20 feature, which is not shared with the APC40, is Note Mode. The APC20 can be put into Note Mode using the Note Mode button (which was the Master Select button on the APC40). This allows the 8x5 grid to be used for sending MIDI notes - to control a drum rack, for example. So, is there a Note Mode on the APC40?
Sysex is used to set the APC modes, and while APC40 has 3 documented modes, the APC20 has 4. As shown in the APC40 Communications Protocol document, a “Type 0” sysex message is used to set the APC40’s Modes. Byte 8 is the Mode identifier: 0x40 (decimal 64) Generic Mode 0x41 (decimal 65) Ableton Live Mode 0x42 (decimal 66) Alternate Ableton Live Mode
The 8.1.3 MIDI remote scripts show that a new Mode byte value has been added for the APC20: 0x43 (decimal 67) APC20 Note Mode
Unfortunately, this new Mode value (0x43) is meaningless to the APC40 – the hardware does not respond to this value. This is not a remote script limitation, but rather a fir mware update would be required in order to for the APC40 to have a Note Mode. So far, none is available. On the other hand, it might well be possible to create a script which emulates Note Mode by translating MIDI Note and Channel data on the fly (there is already a Framework method for channel translation, which could be a good place to start). A future scripting project, perhaps, if Akai decides not to provide firmware updates for the APC40. Further investigation of the 8.1.3 scripts shows that the structure of the APC40 remote scripts has changed somewhat, in order to accommodate the APC20. Both the APC20 and the APC40 classes are now sub-classes of an APC ‘super’ class. The APC class now handles the handshake, and other methods common to both models. There is also a new APCSessionComponent module, which is used for linking multiple APCs (this module appears to ha ndle “red box” offsets, so that multiple session boxes for multiple APCs will sit side -byside). Here is the docstring for the class: class APCSessionComponent(SessionComponent): " Special SessionComponent for the APC controllers' combination mode " Otherwise, little seems to hav e changed between 8.1.1 and 8.1.3. In fact, our A PC40plus1 script runs without error on 8.1.3, even though it was based on 8.1.1 code. Which is good news. Now, just for fun, we can try to emulate an APC20 using an APC40, by overriding the sysex bytes for Product ID and Mode. The product_model_id bytes for the A PC20 would be 123 - for the APC40 it’s 115 (or hex 0x73, as listed in the APC40 Communications Protocol document). So, we need to modify the APC20 script as follows: def _product_model_id_byte(self): return 115 #was originally 123 And, in the APC20 consts.py file, we need to change the Note Mode value from 67 to 65: MANUFACTURER_ID = 71 ABLETON_MODE = 65 NOTE_MODE = 65 #Was: 67 (= APC20 Note Mode); 65 = APC40 Ableton Mode 1
Well, the emulation does work, but of course, an APC40 is only half alive in APC20 mode – the right hand side is completely inactive – and Note Mode does nothing (yet). On the other hand, the ability to use the shift + record buttons to re-assign sliders is a nice feature. It would of course be possible to build a hybrid script which combines features from both the APC20 and the APC40 scripts, i f anyone felt so inclined. Simply a question of finding the time - and we all know that there's never enough of that... Conclusion
The MIDI remote scripts, and particularly the Framework classes, provide a convenient and relatively straight-forward mechanism for tailoring the operation of control surfaces - with or without Max for Liv e.
The Live 8 scripts do cater to Max for Live, but maintain the same basic functionality they’ve always had. The APC40 scripts provide a good example of this, as do the new APC20 scripts - both of which provide a good platform for customization. Well, happy scripting - and remember to share your discoveries and custom scripts with the rest of the Live community! Hanz Petrov April 13, 2010
Introduction to the Framework Classes Part 3 Introduction
As we’ve demonstrated previously, the _Framework classes provide a very useful framework for coding MIDI control surface scripts in Python. We’ve looked at basic script setup, worked with simple Control Surface components and objects, and over-ridden hig h-level setup methods to achieve certain customization goals. Here in this post, we’ll have a look at the relationship between the _Framework classes and the “special” subclass modules which are used with many of the Framework-based MIDI remote scripts for newer controllers. As a working example, we’ll be adding APC20 functionality to the APC40 by modifying the APC40’s MIDI remote scripts. Our modifications will include Note Mode for the matrix, and User Mode for the sliders. We’ll also have another look at Device Lock, create mappings for Undo and Redo, and re- map the APC40’s endless encoder to control Tempo. For those who wish to follow along, the complete Python source files which accompany this article can be downloaded here. Sysex and Subclasses
As we’ve seen previously, the APC20 can be put into Note Mode by sending an appropriate Sysex string to the controller. In this mode, the 8x5 matrix can be used to send MIDI n otes, trigger samples, control drum racks, etc. - similar to the Launchpad’s User modes. For the APC40, however, a firmware upgrade would be required in order enable Note Mode via Sysex. Fortunately, Sysex is not the only way. The Launchpad’s User Modes do not rely on Sysex, and w e can use the same approach to add a Note Mode to the APC4 0. Before we do, however, let’s collect the scripts we need in order to combine the useful new features of the APC20 with those of the APC40. In Live 8.1.3, the APC20 and APC40 scripts are both subclasses of the APC “super -class” script, although the APC module actually resides in the APC40 folder, while the APC20 scripts are found in a separate folder. Here, we’ll copy all of the required scripts over into a new folder, which we’ll call APC40_20. Our modified controller script will then be selectable in L ive’s MIDI preferences drop -down list as APC40_20. Since any “shifted” controls generally require a new subclass (as they inherit from and override Framework base class methods), and since many of the controls on both the APC40 and on the APC20 work in a shifted mode, we’ll need to include a fair number of “special” subclass modules. Here is a list of the modules we’ll be needing (in addition to the Framework modules, which are not listed): __init__.py APC.py (APC40 and APC20) APC40plus20.py (based on APC40 script) APCSessionComponent.py (APC20) ConfigurableButtonElement.py (Launchpad) DetailViewControllerComponent.py (APC40) EncoderMixerModeSelectorComponent.py (APC40) PedaledSessionComponent.py (APC40) RingedEncoderElement.py (APC40) ShiftableDeviceComponent.py (APC40) ShiftableSelectorComponent.py (APC20) ShiftableTranslatorComponent.py (APC40) ShiftableTransportComponent.py (APC40) ShiftableZoomingComponent.py (APC20) SliderModesComponent.py (APC20) SpecialChannelStripComponent.py (APC40) SpecialMixerComponent.py (APC40) SpecialTransportComponent.py (APC40)
Note that we’ve included one non -APC module here, ConfigurableButtonElement, which is from the Launchpad scripts. One advantage of using the Framework classes for scripting is that special subclass modules are generally re-usable and interchangeable, especially for similar control surfaces.
Now, with all of the subclass scripts gathered together in one place (for ease of editing and transportability), we’ll merge the APC20 and APC40 scripts. Both of these scripts are Framework-based, so there will be some import duplicates, which we can eliminate. There are also some APC20 special subclass modules which we will be using instead of the APC40’s plain vanilla Framework imports. Here is the merged import list: import Live from APC import APC from _Framework.ControlSurface import ControlSurface from _Framework.InputControlEl ement import * from _Framework.SliderElement import SliderElement from _Framework.ButtonElement import ButtonElement from _Framework.EncoderElement import EncoderElement from _Framework.ButtonMatrixEl ement import ButtonMatrixElement from _Framework.MixerComponent import MixerComponent from _Framework.ClipSlotCompon ent import ClipSlotComponent from _Framework.ChannelStripCo mponent import ChannelStripComponent from _Framework.SceneComponent import SceneComponent #from _Framework.SessionZoomingComponent import SessionZoomingComponent #use ShiftableZoomingComponent from APC20 scripts instead from _Framework.ChannelTransla tionSelector import ChannelTranslationSelector from EncoderMixerModeSelectorComponent import EncoderMixerModeSelectorComponent from RingedEncoderElement import RingedEncoderElement from DetailViewControllerComponent import DetailViewControllerComponent from ShiftableDeviceComponent import ShiftableDeviceComponent from ShiftableTransportComponent import ShiftableTransportComponent from ShiftableTranslatorComponent import ShiftableTranslatorComponent from PedaledSessionComponent import PedaledSessionComponent from SpecialMixerComponent import SpecialMixerComponent # Additional imports from APC20.py: from ShiftableZoomingComponent import ShiftableZoomingComponent from ShiftableSelectorComponent import ShiftableSelectorComponent from SliderModesComponent import SliderModesComponent # Import added from Launchpad scripts - needed for Note Mode: from ConfigurableButtonElement import ConfigurableButtonElement Next we compare the APC20 and APC40 scripts for differences, retaining the most useful parts of each. Since most of the setting-up in th e APC20 script setup is identi cal to that of APC40, and since the APC40 has more controls than the APC20, we’ll base our modified script on APC40 script, adding relevant code from the APC20 script as needed. The basic set-up of our script includes the following components: SessionComponent (includes session matrix, “red box” navigation controls, scene and clip launch buttons, and stop buttons) SessionZoomingComponent (includes “zoomed out” controls: matrix, selection, navigation, etc., for “banks of scenes”) MixerComponent (includes solo, mute, arm, and volume controls for tracks) TransportComponent (includes play, stop, record, tempo, metronome, quantize, etc., for song) DeviceComponent (includes device control, device on-off, device nav igation, etc.)
These are basic Framework components, however, with a complex controller like the A PC40, most are actually instantiated as special subclass objects. The special subclass modules are typically used for overriding existing Framework class methods, and for adding new methods - and often include direct calls to the LiveAPI. However, since they generally provide easily understood features, their usage is straight-forward and we can include most of them as-is, without modification, and without further i nvestigation. We do need
to sort out the conflicts between the APC40 and APC20 scripts, however - and add new code where we want to do new things or do things in different ways. It turns out that the only speci al modules which we’ll need to modify here are the following: SpecialMixerComponent.py – we will map Cue Level to Tempo here ShiftableDeviceComponent.py – we will check the Device Lock state here ShiftableSelectorComponent.py – we will implement Note Mode here ShiftableTransportComponent.py – we will add Undo and Redo, and handle the true endless encoder here ShiftableZoomingComponent.py – we will modify the scope of Note Mode here (keep scene launch active)
Mapping Cue Level to Tempo provides a good example of subclass modification. It turns out that there is only one true endless encoder on the APC40/20, which is the Cue Level control. This is the control which we want to use as a Tempo control, due to its unique placement on the board. Un fortunately, however, the simple set_tempo_control Framework TransportComponent method, which we would normally use, throws an assertion error when mapped to a true endless encoder: def set_tempo_control(self, control, fine_control = None): assert ((control == None) or (isinstance(control, EncoderElement) and (control.message_map_mode() is Live.MidiMap.MapMode.absolute))) assert ((fine_control == None) or (isinstance(fine_control, EncoderElement) and (fine_control.message_map_mode() is Live.MidiMap.MapMode.absolute))) Our true endless encoder is an EncoderElement with a map_mode value of Live.MidiMap.MapMode.relative_two_compliment , not Live.MidiMap.MapMode.absolute, so, we’ll need to dig deeper. Luckily, there’s an “old-fashioned” script which show s us the way - we can adapt code from the Mackie Control script to suit our purpose here (the Mackie jog wheel is also a true endless encoder). In the ShiftableTransportComponent module, we add a method for assigning the control, which now will th row an assertion error if the mapped control is not an endless encoder: def set_tempo_encoder(self, control): assert ((control == None) or (isinstance(control, EncoderElement) and (control.message_map_mode() is Live.MidiMap.MapMode.relative_two_compliment))) if (self._tempo_encoder_control != None): self._tempo_encoder_control.remove_value_listener(self._tempo_encoder_value) self._tempo_encoder_control = control if (self._tempo_encoder_control != None): self._tempo_encoder_control.add_value_listener(self._tempo_encoder_value) self.update() And we need to add the callback (i.e., the “listener value”). This is the method which is called whenever the controller (encoder) is adjusted:
def _tempo_encoder_value(self, value): if not self._shift_pressed: assert (self._tempo_encoder_control != None) assert (value in range(128)) backwards = (value >= 64) step = 0.1 #step = 1.0 #reduce this for finer control; 1.0 is 1 bpm if backwards: amount = (value - 128) else:
amount = value tempo = max(20, min(999, (self.song().tempo + (amount * step)))) self.song().tempo = tempo
Note that we’ve changed the step increment to a reasonably smooth value of 0.1 bpm, since we’re only using one encoder for tempo control here (the Framework basic transport.set_tempo_control method, which we’re not using, is actually set up to accept two controller assignments - one for coarse tuning and one for fine tempo tuning). If we wanted to, we could also adjust the Tempo range min and max values here as well.
We can see that the _tempo_encoder_value method ends with a call to the LiveAPI; self.song().tempo = tempo. The LiveAPI is well documented, so these types of calls are easy to look up, when they're not easliy understood at first glance. We can also refer to the many MIDI remote scri pts, and the _Framework scripts themselves, for examples of how to make the calls and what arguments to use. In the _tempo_encoder_value method above, we check to see if shift is pressed before doing anything else, because we want to revert to the original Cue Volume mapping when in shifted mod e. We’ll also need to add some code to the SpecialMixerComponent module to do this. The _shift_value method is called when the shift button is pressed, which in turn calls the update() method; this is where we’ll connect our “prehear” (Cue Volume) control - right before the Crossfader control connection is made: def _shift_value(self, value): #added assert (self._shift_button != None) assert (value in range(128)) self._shift_pressed = (value != 0) self.update() def update(self): #added override if self._allow_updates: master_track = self.song().master_track if self.is_enabled(): if (self._prehear_volume_control != None): if self._shift_pressed: #added self._prehear_volume_control.connect_to(master_track.mixer_device.cue_volume) else: self._prehear_volume_control.release_parameter() #added if (self._crossfader_control != None): self._crossfader_control.connect_to(master_track.mixer_device.crossfader) else: if (self._prehear_volume_control != None): self._prehear_volume_control.release_parameter() if (self._crossfader_control != None): self._crossfader_control.release_parameter() if (self._bank_up_button != None): self._bank_up_button.turn_off() if (self._bank_down_button != None): self._bank_down_button.turn_off() if (self._next_track_button != None): self._next_track_button.turn_off() if (self._prev_track_button != None): self._prev_track_button.turn_off() self._rebuild_callback() else:
self._update_requests += 1
So far, so good. With some higher -level remote script adjustments and some lower-level subclass code modifications, we’ve successfully mapped Cue Level to Tempo. Now, on to Note Mode. Note Mode
In order to enable Note Mode, first we need to disable the clip slots, so that we can re-assign the matrix buttons to the MIDI notes of our chosing. We don’t want to totally disconnect the ButtonElements , we only want to change the mappings. The original APC20 script actually disables the SessionComponent altogether, however, this also puts the Scene Launch and Track Stop buttons out of action. To take out only the matrix, we need to disable the clip slots, and nothing else. We’ll do this in the set_ignore_buttons method of theShiftableZoomingComponent class: def set_ignore_buttons(self, ignore): assert isinstance(ignore, type(False)) if (self._ignore_buttons != ignore): #if ignore state changes.. self._ignore_buttons = ignore #set new state if (not self._is_zoomed_out): #if in session/clip view.. if ignore: #disable clip slots on ignore for scene_index in range(5): scene = self._session.scene(scene_index) for track_index in range(8): clip_slot = scene.clip_slot(track_index) clip_slot.set_enabled(False) else: #re-enable clip slots on ignore for scene_index in range(5): scene = self._session.scene(scene_index) for track_index in range(8): clip_slot = scene.clip_slot(track_index) clip_slot.set_enabled(True) #self._session.set_enabled((not ignore)) self.update()
Now that the clip slots are disabled, we can re- map the matrix buttons to MIDI notes. We’ll do this in the _on_note_mode_changed method of the ShiftableSelectorComponent class. We’ll use a note layout which is similar to the APC20’s Note Mode layout, and to the Launchpad’s User 1 mode layout – both of which are based on split rows. Each half row will ascend in sets of 4 notes, which works well with the typical Live Rack (also 4 notes wide). Here 's a map of our new Note Mode layout (together with the other mods i n our script):
In order to avoid conflict with the APC40 a ssignments, we’ll send all of our Note Mode notes out on channel 10 (the APC40 uses channels 1 through 8 - and possibly 9, according to the original note map). To map the notes and to change the channels, we’ll use the Framework set_channel and set_identifier methods. We’ll also use the Framework button.send_value method to create different colour patterns for the left and right sides of the grid – so that our note mapping is visually obvious. Here’s the code:
def _on_note_mode_changed(self): if not self._master_button != None: raise AssertionError if self.is_enabled() and self._invert_assignment == self._toggle_pressed: if self._note_mode_active: self._master_button.turn_on() for scene_index in range(5): #TODO: re-map scene_launch buttons to note velocity... scene = self._session.scene(scene_index) for track_index in range(8): clip_slot = scene.clip_slot(track_index) button = self._matrix.get_button(track_index, scene_index) clip_slot.set_launch_button(None) button.set_enabled(False) button.set_channel(9) #remap all Note Mode notes to channel 10 if track_index < 4: button.set_identifier(52 - (4 * scene_index) + track_index) #top row of left group (first 4 columns) notes 52 to 55 if (track_index % 2 == 0 and scene_index % 2 != 0) or (track_index % 2 != 0 and scene_index % 2 == 0): button.send_value(1) #0=off, 1=green, 2=green blink, 3=red, 4=red blink, 5=yellow, 6=yellow blink, 7-127=green else: button.send_value(5) else: button.set_identifier(72 - (4 * scene_index) + (track_index -4)) #top row of right group (next 4 columns) notes 72 to 75 if (track_index % 2 == 0 and scene_index % 2 != 0) or (track_index % 2 != 0 and scene_index % 2 == 0):
button.send_value(1) #0=off, 1=green, 2=green blink, 3=red, 4=red blink, 5=yellow, 6=yellow blink, 7-127=green else: button.send_value(3) self._rebuild_callback() else: self._master_button.turn_off() return None
Of course, we need to turn the lights off and re-enable the clip slots when Note Mode is switched back off. We’ll do that in the _master_value method (which is also where the APC20 Sysex Note Mode string normally gets queued-up): def _master_value(self, value): #this is the master_button value_listener, i.e. called when the master_button is pressed if not self._master_button != None: raise AssertionError if not value in range(128): raise AssertionError if self.is_enabled() and self._invert_assignment == self._toggle_pressed: if not self._master_button.is_momentary() or value > 0: #if the master button is pressed: #for button in self._select_buttons: #turn off track select buttons (only needed for APC20) #button.turn_off() self._matrix.reset() #turn off the clip launch grid LEDs #mode_byte = NOTE_MODE #= 67 for APC20 Note Mode, send as part of sysex string to e nable Note Mode if self._note_mode_active: #if note mode is already on, turn it off: #mode_byte = ABLETON_MODE #= 65 for APC40 Ableton Mode 1 for scene_index in range(5): scene = self._session.scene(scene_index) for track_index in range(8): clip_slot = scene.clip_slot(track_index) button = self._matrix.get_button(track_index, scene_index) clip_slot.set_launch_button(button) button.set_enabled(True) button.turn_off() self._rebuild_callback() #self._mode_callback(mode_byte) #send sysex to set Mode (NOTE_MODE or ABLETON_MODE) self._note_mode_active = not self._note_mode_active self._zooming.set_ignore_buttons(self._note_mode_active) #turn off matrix, scene launch, and clip stop buttons when in Note Mode #self._transport.update() #only needed for APC20 self._on_note_mode_changed() return None So now we have a working Note Mode on the APC40 (don’t forget that we do have to enable the MIDI Input Track switch in Live's MIDI preferences dialog, so that our notes get passed along to the track). Not too difficult, was it? Of course, I wouldn’t expect to see official support for Note Mode on the APC40 from Ableton or Akai anytime soon, if only because thousands of units are already out there, without any red stenciling to tell users which bu tton to press to enable Note Mode – and they might get confuse d. Well, that,
and it might hurt sales of the APC20. Undo/Redo Now, before we sign off, we’ll take a minute and re -map the Tempo Nudge buttons to Undo and Redo. It just so happens that the OpenLabs scripts have a nice SpecialTransportComponent module, which provides methods for setting Undo, Redo, and Back to Start (BTS) buttons; we’ll copy the required code over to our equivalent ShiftableTransportComponent module. Here is the Undo code (Redo is almost identical):
def set_undo_button(self, undo_button): assert isinstance(undo_button, (ButtonElement, type(None))) if (undo_button != self._undo_button): if (self._undo_button != None): self._undo_button.remove_value_listener(self._undo_value) self._undo_button = undo_button if (self._undo_button != None): self._undo_button.add_value_listener(self._undo_value) self.update() And the callback (featuring some more LiveAPI calls): def _undo_value(self, value): assert (self._undo_button != None) assert (value in range(128)) if self.is_enabled(): if ((value != 0) or (not self._undo_button.is_momentary())): if self.song().can_undo: self.song().undo() Conclusion Well, that’s it for now. We’ve shown that implementing Note Mode on the APC40 is relatively straight forward, and does not in fact require a firmware update. We’ve also demonstrated that much can be accomplished simply by extending Framework-based scripts and subclasses. Our custom tweaks and mappings do not require templates or add -ons, and best part is that they are free – free as in free beer! Cheers.
Hanz Petrov May 13, 2010 hanz.petrov at gmail.com PostScript: It would seem that many (if not all) of the Live MIDI remote scripts, for all of the various control surfaces, were coded by Jan B. over at Ableton. His code is a pleasure to work with and fun to learn from my appreciation goes out to Jan and to the entire Ableton team.
Introduction to the Framework Classes Part 4 - the Final Chapter Introduction
In Part 1 of this series, I mentioned that my journey into the world of MIDI remote scripts began with a search for a better way of integrating my FCB1010 foot controller into my Live setup. Well, it’s been a fun trip - with lots of interesting side investigations along the way - but now we’ve come full circle and it’s time to finish up what I set out to do in the beginning. In this article, we’ll have a look a couple of new _Framework methods introduced in version 8.1.3, which will allow us to operate scripts in Combination Mode, and we’ll create a generic script which will allow the FCB1010 to work in concert with the APC40 – in fact, we’ll set it up to emulate the APC40. And then we’re pretty much done. Let’s start with combination mode. Combination Mode – red and yellow and pink and green…
As we saw in Part 1, set_show_highlight , a SessionComponent method, can be used to display the famous “red box”, which represents the portion of a Session View which a control surface is controlling. First seen with the APC40 and Launchpad, the red box is a must have for any clip launcher. New since 8.1.4, however, is a functional Combination Mode – specifically announced for the APC40 and APC 20 – which “glues” two or more session highlights together. From the 8.1.4 changelog: “Combination Mode is now active when multiple Akai APC40/20s are in use. This means that the topmost controller selected in your preferences will control tracks 1-8, the second controller selected will control tracks 9-16, and so on.”
Sounds like fun – let’s see how it’s done. By looking through the APC sources, we can work our way back to the essential change at work here: the SessionComponent class now has new methods called _link and _unlink (together with a new attribute _is_linked , and a new list object known as _linked_session_instances ). Linking sessions turns out to be no more difficult than calling the SessionComponent’s _link method, as follows: session = SessionComponent(num_tracks, num_scenes) session._link()
Now, although multiple session boxes can be linked in this way, we need to manage our session offsets, if we want our sessions to sit bes ide each other, and not one on top of the other. In other words, we will need to sequentially assign non-zero offsets to our linked sessions, based on the adjacent session’s width. We'll add the required code to the ProjectX script from Part 1, as an illustration. First, we’ll need a list object to hold the active instances of our ProjectX ControlSurface class, and a static method which will be called at the end of initialisation: _active_instances = []
def _combine_active_instances(): track_offset = 0 for instance in ProjectX._active_instances: instance._activate_combination_mode(track_offset) track_offset += session.width() _combine_active_instances = staticmethod(_combine_active_instances)
We add a _do_combine call at the end of our init sequence, which in turn calls the _combine_active_instances static method – and _combine_active_instances calls _activate_combination_mode on each instance.
def _do_combine(self): if self not in ProjectX._active_instances: ProjectX._active_instances.append(self) ProjectX._combine_active_instances() def _activate_combination_mode(self, track_offset): if session._is_linked(): session._unlink() session.set_offsets(track_offset, 0) session._link() Now that the linking is all set up, we’ll define a _do_uncombine method, to clean things up when we disconnect; we’ll unlink our SessionComponent and remove ourselves from the list of active instances here.
def _do_uncombine(self): if ((self in ProjectX._active_instances) and ProjectX._active_instances.remove(self)): self._session.unlink() ProjectX._combine_active_instances() def disconnect(self): self._do_uncombine() ControlSurface.disconnect(self) So here’s what we get when we load several instances of our new ProjectX script via Live's MIDI preferences dialog:
The session highlights are all linked (with an automatic track offset for each instance, which matches the adjacent session highlight width), and when we move any one of them, the others move along together. By changing the offsets in _activate_combination_mode , we can get them to stack side-by-side, or one above the other, or if we wanted to, we could indeed stack them one on top of the other . By stacking them one on top of the other, we can control a si ngle session highlight zone wi th multiple controllers – which is exactly what we want to do with th e APC40 and FCB1010 in combination mode. As of version 8.1.3, the Framework scripts have included support for session linking, but so far, the only official scripts which implement combination mode are the APC scripts (as of 8.1.4). As shown above, however, support for combination mode can be extended to pretty much any Framework-based script. What we want to create then, is a script which will allow the FCB1010 to operate in combination m ode together with the APC40. Let’s build one.
FCB1020 - a new script for the FCB1010
The first thing to do when setting out to create a new script is to decide on a functional layout. If we know what we’re trying to achieve in terms of functionality and operation - before we touch a line of code - we can save ourselves a good deal of time down the road. In this case, we’re looking for an arrangement which will allow the FCB1010 to mirror the operation of the AP C40, in so far as possible, and allow for optimized hands-free operation. Although the options for designing a control script are almost unlimited, generally, the resulting meth od of operation needs to be intuitive. The FCB1010 has some built-in constraints, but also offers a great deal of flexibility. We have 10 banks of 10 switches and 2 pedals to work with – equivalent to 100 “button” controls and 20 “sliders”. Interestingly, the APC40 has a similar number of buttons an d knobs. If we look at the two controllers side -by-side, a pattern emerges. Each column of the APC40’s grid consists of 5 clip launch buttons (one per scene) and 5 track control buttons (clip stop, track select, activate, solo, & record). Each of the FCB 1010’s 10 banks has 5 switches on the top row, and 5 switches on the bottom row. Based on this parallel, if we assign one FCB1010 bank to each of the APC40’s track columns, the resulting operation will indeed be intuitive, and will closely follow the APC’s layout. We only have 2 pedals per bank, however, so we’ll map them to Track Volume, and Send A – at least for now. Here’s how a typical FCB1010 bank will lay out, together with the A PC40 layout for comparison.
Bank 01
APC40
We’ll use this layout for banks 1 through 8 (since the APC40 has 8 track control columns), but because the
FCB1010 has 10 banks in total, we have 2 banks left over. Let’s use bank 00 for the Master Track controls, and the scene launch controls, in a similar arrangement to banks 1 through 8. There are no activate, solo or record buttons for the master track, so instead, we’ll map global play, stop and record here:
Bank 00
Now we only have one bank left - bank 09. We’ll use bank 09 for session and track navigation, and for device control. Here’s how it will look:
Bank 09
Although fairly intuitive, the layout described above might not suit everyone’s preferences. Wouldn’t it be nice if the end user could decide on his or her own preferred layout? Live’s User Remote Scripts allow for this kind of thing, so we’ll take a similar approach. Rather than hard -coding the note and controller mappings deep within our new script, we’ll pull all of the assignments out into a separate file, for easy access and editing. It will rem ain a python .py file (not a .txt file) - in the tradition of consts.py, of Mackie emulation fame - but since .py files are simple text files, they can be edited using any text editor. We’ll call our file MIDI_map.py . Here’s a sample of what it will contain:
# General PLAY = 7 #Global play STOP = 8 #Global stop REC = 9 #Global record TAPTEMPO = -1 #Tap tempo NUDGEUP = -1 #Tempo Nudge Up NUDGEDOWN = -1 #Tempo Nudge Down UNDO = -1 #Undo REDO = -1 #Redo LOOP = -1 #Loop on/off PUNCHIN = -1 #Punch in PUNCHOUT = -1 #Punch out OVERDUB = -1 #Overdub on/off METRONOME = -1 #Metronome on/off RECQUANT = -1 #Record quantization on/off DETAILVIEW = -1 #Detail view switch CLIPTRACKVIEW = -1 #Clip/Track view switch
# Device Control DEVICELOCK = 99 #Device Lock (lock "blue hand") DEVICEONOFF = 94 #Device on/off DEVICENAVLEFT = 92 #Device nav left DEVICENAVRIGHT = 93 #Device nav right DEVICEBANKNAVLEFT = -1 #Device bank nav left DEVICEBANKNAVRIGHT = -1 #Device bank nav right # Arrangement View Controls SEEKFWD = -1 #Seek forward SEEKRWD = -1 #Seek rewind # Session Navigation (aka "red box") SESSIONLEFT = 95 #Session left SESSIONRIGHT = 96 #Session right SESSIONUP = -1 #Session up SESSIONDOWN = -1 #Session down ZOOMUP = 97 #Session Zoom up ZOOMDOWN = 98 #Session Zoom down ZOOMLEFT = -1 #Session Zoom left ZOOMRIGHT = -1 #Session Zoom right # Track Navigation TRACKLEFT = 90 #Track left TRACKRIGHT = 91 #Track right # Scene Navigation SCENEUP = -1 #Scene down SCENEDN = -1 #Scene up # Scene Launch SELSCENELAUNCH = -1 #Selected scene launch Now we can easily change the layout of any of our banks, by editing this one file. In fact, pretty much anything goes – if we wanted to, we could hav e different layouts for each of the 10 banks, or leave some banks unassigned, for use with guitar effects, etc. To help with layout planning, an editable PDF template for the FCB1010 is included with the source code on the Support Files page. Okay, so now it’s time to assemble the code. Since we’re essentially emulating the APC40 here (yes, I admit that I was wrong in Part 2; APC40 emulation is not so crazy after all), we h ave a choice between starting with the APC scripts and customizing, or building a new set of scripts which have si milar functionality. Since we won’t be supporting shifted operations in our script (for the FCB1010 this would require operation with two feet – difficult to do in an upright position), we will need to make si gnificant changes to the APC scripts. Starting from scratch is definitely an option worth considering. On the other hand, the APC40 script will make for a good roadmap, and while we’re at it, we can include some of the special features of the APC40_22 script from Part 3 here as well. The structure will be fairly simple. We’ll have an __init__.py module (to identify the directory as a python package), a main module (called FCB1020.py ), a MIDI_map.py constants file, and several “special” Framework component override modules. Here’s the file list (compete source code is available on the Support Files page): __init__.py FCB1020.py MIDI_Map.py
SpecialChannelStripComponent.py SpecialMixerComponent.py SpecialSessionComponent.py SpecialTransportComponent.py SpecialViewControllerComponent.py SpecialZoomingComponent.py We won’t go into detail on the Special components, since that topic was covered in Part 3. The main module follows the structure outlined in Part 1, but here's a quick overview. We start with the imports, and then define the combination mode static method (as discussed above):
import Live from _Framework.ControlSurface import ControlSurface from _Framework.InputControlEl ement import * from _Framework.SliderElement import SliderElement from _Framework.ButtonElement import ButtonElement from _Framework.ButtonMatrixEl ement import ButtonMatrixElement from _Framework.ChannelStripCo mponent import ChannelStripComponent from _Framework.DeviceComponen t import DeviceComponent from _Framework.ControlSurface Component import ControlSurfaceComponent from _Framework.SessionZooming Component import SessionZoomingComponent from SpecialMixerComponent import SpecialMixerComponent from SpecialTransportComponent import SpecialTransportComponent from SpecialSessionComponent import SpecialSessionComponent from SpecialZoomingComponent import SpecialZoomingComponent from SpecialViewControllerComponent import DetailViewControllerComponent from MIDI_Map import * class FCB1020(ControlSurface): __doc__ = " Script for FCB1010 in APC emulation mode " _active_instances = [] def _combine_active_instances(): track_offset = 0 scene_offset = 0 for instance in FCB1020._active_instances: instance._activate_combination_mode(track_offset, scene_offset) track_offset += instance._session.width() _combine_active_instances = staticmethod(_combine_active_instances) Next we have our init method, where we instantiate our ControlSurface component and call the various setup methods. We setup the session, then setup the mixer, then assign the mixer to the session, to keep them in sync. The disconnect method follows, where we provide some cleanup f or when the control surface is disconnected: def __init__(self, c_instance): ControlSurface.__init__(self, c_instance) self.set_suppress_rebuild_requests(True) self._note_map = [] self._ctrl_map = [] self._load_MIDI_map() self._session = None self._session_zoom = None self._mixer = None self._setup_session_control() self._setup_mixer_control()
self._session.set_mixer(self._mixer) self._setup_device_and_transport_control() self.set_suppress_rebuild_requests(False) self._pads = [] self._load_pad_translations() self._do_combine()
def disconnect(self): self._note_map = None self._ctrl_map = None self._pads = None self._do_uncombine() self._shift_button = None self._session = None self._session_zoom = None self._mixer = None ControlSurface.disconnect(self) The balance of the combination mode methods are next: def _do_combine(self): if self not in FCB1020._active_instances: FCB1020._active_instances.append(self) FCB1020._combine_active_instances() def _do_uncombine(self): if ((self in FCB1020._active_instances) and FCB1020._active_instances.remove(self)): self._session.unlink() FCB1020._combine_active_instances() def _activate_combination_mode(self, track_offset, scene_offset): if TRACK_OFFSET != -1: track_offset = TRACK_OFFSET if SCENE_OFFSET != -1: scene_offset = SCENE_OFFSET self._session.link_with_track_offset(track_offset, scene_offset) The session setup is based on Framework SessionComponent methods, with SessionZoomingComponent navigation thrown in for good measure: def _setup_session_control(self): is_momentary = True self._session = SpecialSessionComponent(8, 5) self._session.name = 'Session_Control' self._session.set_track_bank_buttons(self._note_map[SESSIONRIGHT], self._note_map[SESSIONLEFT]) self._session.set_scene_bank_buttons(self._note_map[SESSIONDOWN], self._note_map[SESSIONUP]) self._session.set_select_buttons(self._note_map[SCENEDN], self._note_map[SCENEUP]) self._scene_launch_buttons = [self._note_map[SCENELAUNCH[index]] for index in range(5) ] self._track_stop_buttons = [self._note_map[TRACKSTOP[index]] for index in range(8) ]
self._session.set_stop_all_clips_button(self._note_map[STOPALLCLIPS]) self._session.set_stop_track_clip_buttons(tuple(self._track_stop_buttons)) self._session.set_stop_track_clip_value(2) self._session.selected_scene().name = 'Selected_Scene' self._session.selected_scene().set_launch_button(self._note_map[SELSCENELAUNC H]) self._session.set_slot_launch_button(self._note_map[SELCLIPLAUNCH]) for scene_index in range(5): scene = self._session.scene(scene_index) scene.name = 'Scene_' + str(scene_index) button_row = [] scene.set_launch_button(self._scene_launch_buttons[scene_index]) scene.set_triggered_value(2) for track_index in range(8): button = self._note_map[CLIPNOTEMAP[scene_index][track_index]] button_row.append(button) clip_slot = scene.clip_slot(track_index) clip_slot.name = str(track_index) + '_Clip_Slot_' + str(scene_index) clip_slot.set_launch_button(button) self._session_zoom = SpecialZoomingComponent(self._session) self._session_zoom.name = 'Session_Overview' self._session_zoom.set_nav_buttons(self._note_map[ZOOMUP], self._note_map[ZOOMDOWN], self._note_map[ZOOMLEFT], self._note_map[ZOOMRIGHT])
Mixer, device, and transport setup methods are similar. def _setup_mixer_control(self): is_momentary = True self._mixer = SpecialMixerComponent(8) self._mixer.name = 'Mixer' self._mixer.master_strip().name = 'Master_Channel_Strip' self._mixer.master_strip().set_select_button(self._note_map[MASTERSEL]) self._mixer.selected_strip().name = 'Selected_Channel_Strip' self._mixer.set_select_buttons(self._note_map[TRACKRIGHT], self._note_map[TRACKLEFT]) self._mixer.set_crossfader_control(self._ctrl_map[CROSSFADER]) self._mixer.set_prehear_volume_control(self._ctrl_map[CUELEVEL]) self._mixer.master_strip().set_volume_control(self._ctrl_map[MASTERVOLUME]) for track in range(8): strip = self._mixer.channel_strip(track) strip.name = 'Channel_Strip_' + str(track) strip.set_arm_button(self._note_map[TRACKREC[track]]) strip.set_solo_button(self._note_map[TRACKSOLO[track]]) strip.set_mute_button(self._note_map[TRACKMUTE[track]]) strip.set_select_button(self._note_map[TRACKSEL[track]]) strip.set_volume_control(self._ctrl_map[TRACKVOL[track]]) strip.set_pan_control(self._ctrl_map[TRACKPAN[track]]) strip.set_send_controls((self._ctrl_map[TRACKSENDA[track]], self._ctrl_map[TRACKSENDB[track]], self._ctrl_map[TRACKSENDC[track]]))
strip.set_invert_mute_feedback(True)
def _setup_device_and_transport_control(self): is_momentary = True self._device = DeviceComponent() self._device.name = 'Device_Component' device_bank_buttons = [] device_param_controls = [] for index in range(8): device_param_controls.append(self._ctrl_map[PARAMCONTROL[index]]) device_bank_buttons.append(self._note_map[DEVICEBANK[index]]) if None not in device_bank_buttons: self._device.set_bank_buttons(tuple(device_bank_buttons)) self._device.set_parameter_controls(tuple(device_param_controls)) self._device.set_on_off_button(self._note_map[DEVICEONOFF]) self._device.set_bank_nav_buttons(self._note_map[DEVICEBANKNAVLEFT], self._note_map[DEVICEBANKNAVRIGHT]) self._device.set_lock_button(self._note_map[DEVICELOCK]) self.set_device_component(self._device) detail_view_toggler = DetailViewControllerComponent() detail_view_toggler.name = 'Detail_View_Control' detail_view_toggler.set_device_clip_toggle_button(self._note_map[CLIPTRACKVIE W]) detail_view_toggler.set_detail_toggle_button(self._note_map[DETAILVIEW]) detail_view_toggler.set_device_nav_buttons(self._note_map[DEVICENAVLEFT], self._note_map[DEVICENAVRIGHT] ) transport = SpecialTransportComponent() transport.name = 'Transport' transport.set_play_button(self._note_map[PLAY]) transport.set_stop_button(self._note_map[STOP]) transport.set_record_button(self._note_map[REC]) transport.set_nudge_buttons(self._note_map[NUDGEUP], self._note_map[NUDGEDOWN]) transport.set_undo_button(self._note_map[UNDO]) transport.set_redo_button(self._note_map[REDO]) transport.set_tap_tempo_button(self._note_map[TAPTEMPO]) transport.set_quant_toggle_button(self._note_map[RECQUANT]) transport.set_overdub_button(self._note_map[OVERDUB]) transport.set_metronome_button(self._note_map[METRONOME]) transport.set_tempo_control(self._ctrl_map[TEMPOCONTROL]) transport.set_loop_button(self._note_map[LOOP]) transport.set_seek_buttons(self._note_map[SEEKFWD], self._note_map[SEEKRWD]) transport.set_punch_buttons(self._note_map[PUNCHIN], self._note_map[PUNCHOUT]) We’ve also included a DetailViewComponent above, which communicates session view changes via the Live API. Next is _on_selected_track_changed , a ControlSurface class method override, which keeps the selected track’s device in focus. And for drum rack note mapping, we’ve included a _load_pad_translationsmethod, which adds x and y offsets to the Drum Rack note and channel assignments, which are set in
the MIDI_map.py file. This allows us to pass the translations array as an argument to the ControlSurface set_pad_translations method in the expected format. def _on_selected_track_changed(self): ControlSurface._on_selected_track_changed(self) track = self.song().view.selected_track device_to_select = track.view.selected_device if device_to_select == None and len(track.devices) > 0: device_to_select = track.devices[0] if device_to_select != None: self.song().view.select_device(device_to_select) self._device_component.set_device(device_to_select) def _load_pad_translations(self): if -1 not in DRUM_PADS: pad = [] for row in range(4): for col in range(4): pad = (col, row, DRUM_PADS[row*4 + col], PADCHANNEL,) self._pads.append(pad) self.set_pad_translations(tuple(self._pads)) Finally, we have _load_MIDI_map. Here, we create a list of ButtonElements and a list of SliderElements . When we make mapping assignments in our MIDI_map.py file, we are actually indexing objects from these lists. By instantiating the ButtonElements and SliderElements as independent objects, we limit the risk of duplicate MIDI assignments, which would preve nt our script from loading. Any pa rticular MIDI note/channel message from a control surface can only be assigned to a single InputControlElement (such as a button or slider), however, an InputControlElement can be used more than once, with different components. This setup also allows us to append None to the end of each list, so that null assignments can be specified in the MIDI_map file, by using -1 in place of a note number (in python, [-1] corresponds to the last element of a list). def _load_MIDI_map(self): is_momentary = True for note in range(128): button = ButtonElement(is_momentary, MIDI_NOTE_TYPE, NOTECHANNEL, note) button.name = 'Note_' + str(note) self._note_map.append(button) self._note_map.append(None) #add None to the end of the list, selectable with [-1] for ctrl in range(128): control = SliderElement(MIDI_CC_TYPE, CTRLCHANNEL, ctrl) control.name = 'Ctrl_' + str(ctrl) self._ctrl_map.append(control) self._ctrl_map.append(None) Now, speaking of MIDI assignments, since all of our mappings are editable, and grouped in a separate file, couldn’t we use our script with just about any control surface, and not only the FCB1010? Yes, indeed we could. Generic APC Emulation
Our new FCB10120 script can be used as a generic APC emulator, since it merely maps MIDI Note and CC input to specific _Framework component functions, mimicking the APC script setup. In fact, none of this is very different from the User script mechanism provided by Ableton - although our script has a few extra
