COMPUT ER GRAPHIC S Lab Manual
ByRaj Ankur Singh
S.N Practical o.
Date
PRACTICAL 1 Write a program in C to implement DDA Algorithm. #include
#include #include #include #include main() { float x,y,x1,y1,x2,y2,dx,dy,length; int gm,gd=DETECT,i; printf("enter the value of x1:\t"); scanf("%f",&x1); printf("enter the value of y1:\t"); scanf("%f",&y1); printf("enter the value of x2:\t"); scanf("%f",&x2); printf("enter the value of y2:\t"); scanf("%f",&y2); detectgraph(&gd,&gm); initgraph(&gd,&gm,"c:\\tc\\bgi"); dx=ab s(x2-x1); dy=abs(y2-y1); if(dx>=dy) { length=dx; } else { length=dy; } dx=(x2-x1)/length;
dy=(y2-y1)/length; x=x1+0.5; y=y1+0.5; i=1; while(i<=length) { putpixel(x,y,15); x=x+dx; y=y+dy; i=i+1; delay(100); } getch(); closegraph(); }
Output
PRACTICAL 2 Write a program in C to implement Bresenham’s Line Drawing Algorithm. #include #include #include #include #include main() { clrscr(); float x1,y1,x2,y2,dx,dy,p; int gm,gd=DETECT,i=1; printf("Enter The Value of x1:"); scanf("%f",&x1); printf("Enter The Value of y1: "); scanf("%f",&y1); printf("Enter The Value of x2: "); scanf("%f",&x2); printf("Enter The Value of y2: "); scanf("%f",&y2); detectgraph(&gd,&gm); initgraph(&gd,&gm,"c:\\tc\\bgi"); dx=abs(x2-x1); dy=abs(y2-y1); p=((2*dy)-dx); while(i<=dx) { putpixel(x1,x2,15); if(p<0) { ++x1;
p=p+(2*dy); } else { ++x1; ++y1; p=p+(2*dy)-(2*dx); } i=i+1; delay(100); } getch(); closegraph(); }
Output
PRACTICAL 3 Write a program in C to implement Mid-Point Circle Algorithm. #include #include #include #include #include main() { float x,y,r,p; int gm,gd=DETECT; printf("Enter the radius: "); scanf("%f",&r); x=0; y=r; detectgraph(&gd,&gm); initgraph(&gd,&gm,"c:\\tc\\bgi"); p=1-r; do { putpixel(200+x,200+y,15); putpixel(200+y,200+x,15); putpixel(200+x,200-y,15); putpixel(200+y,200-x,15); putpixel(200-x,200-y,15); putpixel(200-y,200-x,15); putpixel(200-x,200+y,15); putpixel(200-y,200+x,15); if(p<0) { ++x; p=p+(2*x)+1; }
else { ++x; --y; p=p+(2*x)-(2*y)+1; } delay(100); }while(x
Output
PRACTICAL 4 Write a program in C to implement Bresenham’s Line Drawing Algorithm to rasterize the line. #include #include #include #include #include main() { clrscr(); float x1,y1,x2,y2,x,y,dx,dy,e; int gm,gd=DETECT,i=1; printf("Enter The Value of x1:"); scanf("%f",&x1); printf("Enter The Value of y1: "); scanf("%f",&y1); printf("Enter The Value of x2: "); scanf("%f",&x2); printf("Enter The Value of y2: "); scanf("%f",&y2); detectgraph(&gd,&gm); initgraph(&gd,&gm,"c:\\tc\\bgi"); dx=abs(x2-x1); dy=abs(y2-y1); e=((2*dy)-dx); x=x1; y=y1; while(i<=dx) { putpixel(x,y,15);
while(e>=0) { ++y; e=e-(2*dx); } ++x; e=e+(2*dy); i=i+1; } getch(); closegraph(); }
Output
PRACTICAL 5 Write a program in C to implement Mid-Point Ellipse Algorithm. #include #include #include #include void main() { int gm,gd=DETECT; int Rx,Ry,P10,x,y,a,b,P20; printf("Enter Value of Rx and Ry: "); scanf("%d %d",&Rx,&Ry); x=0; y=Ry; detectgraph(&gd,&gm); initgraph(&gd,&gm,"c:\\tc\\bgi"); P10=(Ry*Ry)-(Rx*Rx)-(Rx*Rx*Ry)+(0.25*Rx*Rx); do { putpixel(200+x,200+y,15); putpixel(200+x,200-y,15); putpixel(200-x,200+y,15); putpixel(200-x,200-y,15); a=(2*Ry*Ry*x)+(2*Ry*Ry); b=(2*Rx*Rx*y)+(2*Rx*Rx); if(P10<0) { x++; P10=P10+a+(Ry*Ry); } else { x++;
y--; P10=P10+a+(Ry*Ry)-b; } delay(100); }while(a>b); P20=((Ry*Ry)*((x+0.5)*(x+0.5)))+((Rx*Rx)*((y-1)*(y-1)))((Rx*Rx)*(Ry*Ry)); a=(2*Ry*Ry*x)+(2*Ry*Ry); b=(2*Rx*Rx*y)+(2*Rx*Rx); do { putpixel(200+x,200+y,15); putpixel(200+x,200-y,15); putpixel(200-x,200+y,15); putpixel(200-x,200-y,15); a=(2*Ry*Ry*x)+(2*Ry*Ry); b=(2*Rx*Rx*y)+(2*Rx*Rx); if(P20>0) { y--; P20=P20-b+(Rx*Rx); } else { x++; y--; P20=P20-b+a+(Rx*Rx); } delay(100); }while(y>0); getch(); closegraph(); }
Output
PRACTICAL 6 Write a program in C to perform translation on a triangle. #include #include #include #include #include void main() { int gd=DETECT, gm,ch; int x1,x2,x3,y1,y2,y3,tx,ty; printf("Enter coordinates of the triangle: "); scanf("%d%d%d%d%d%d",&x1,&y1,&x2,&y2,&x3,&y3); initgraph(&gd,&gm,"c:\\tc\\bgi"); line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); printf("Enter the translation factors: "); scanf("%d%d",&tx,&ty); x1=x1+tx; y1=y1+ty; x2=x2+tx; y2=y2+ty; x3=x3+tx; y3=y3+ty; line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); getche(); closegraph(); }
Output
Enter the translation factors: 45 78
PRACTICAL 7 Write a program in C to perform rotation on a triangle. #include #include #include #include #include void main() { int gd=DETECT, gm,ch; int x1,x2,x3,y1,y2,y3,tx,ty; float rangle; printf("Enter coordinates of the triangle: "); scanf("%d%d%d%d%d%d",&x1,&y1,&x2,&y2,&x3,&y3); initgraph(&gd,&gm,"c:\\tc\\bgi"); line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); printf("Enter the rotation angle:"); scanf("%f",&rangle); rangle=(rangle*3.14)/180; x1=x1*cos(rangle)-y1*sin(rangle); y1=x1*sin(rangle)+y1*cos(rangle); x2=x2*cos(rangle)-y2*sin(rangle); y2=x2*sin(rangle)+y2*cos(rangle); x3=x3*cos(rangle)-y3*sin(rangle); y3=x3*sin(rangle)+y3*cos(rangle); line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); getche(); closegraph(); }
Output
Enter the rotation angle: 10
PRACTICAL 8 Write a program in C to perform scaling on a triangle. #include #include #include #include #include void main() { int gd=DETECT, gm; int x1,x2,x3,y1,y2,y3,sx,sy; printf("Enter coordinates of the triangle: "); scanf("%d %d %d %d %d %d",&x1,&y1,&x2,&y2,&x3,&y3); initgraph(&gd,&gm,"c:\\tc\\bgi"); line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); printf("Enter the scaling factors: "); scanf("%d %d",&sx,&sy); x1=x1*sx; y1=y1*sy; x2=x2*sx; y2=y2*sy; x3=x3*sx; y3=y3*sy; line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); getch(); closegraph(); }
Output
Enter the scaling factors: 2 2
PRACTICAL 9 Write a program in C to perform Reflection on a triangle. #include #include #include #include #include void main() { int gd=DETECT, gm,ch; int x1,x2,x3,y1,y2,y3,x11,x22,x33,y11,y22,y33; float angle; printf("Enter coordinates of the triangle: "); scanf("%d%d%d%d%d%d",&x1,&y1,&x2,&y2,&x3,&y3); initgraph(&gd,&gm,"c:\\tc\\bgi"); line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); printf("Enter the axis of reflection: "); printf("\n1:about x-axis"); printf("\n2:about y-axis\n"); scanf("%d",&ch); cleardevice(); line(x1,y1,x2,y2); line(x2,y2,x3,y3); line(x3,y3,x1,y1); if(ch==1) { x11=x1; y11=180-y1; x22=x2; y22=180-y2; x33=x3; y33=180-y3;
} if(ch==2) { x11=180-x1; y11=y1; x22=180-x2; y22=y2; x33=180-x3; y33=y3; } gotoxy(1,24); line(x11,y11,x22,y22); line(x22,y22,x33,y33); line(x33,y33,x11,y11); getche(); closegraph(); }
Output
Enter the axis of reflection: 1: about x-axis 2: about y-axis 1
Enter the axis of reflection: 1: about x-axis 2: about y-axis 2
