Computer graphics lab manual

1
Computer Graphics LAB
s.no Date content pg.no Sign
1. Digital Differential Analyzer line
drawing algorithm
2. Bresenham’s line drawing algorithm
3. Midpoint circle generation algorithm
4. Creating various types of texts and
fonts
5. Creating two-dimensional objects
6. Two-dimensional translation
7. Two-dimensional scaling
8. Two-dimensional rotation
9. Three-dimensional translation
10. Three-dimensional scaling
11. Three-dimensional rotation
12. Curve generation
13. Moving circle in different directions
14. Man walking using simple animation
15. Coloring the object using
a) 4-connected Floodfill
b) Floodfill function

2
1. DIGITAL DIFFERENTIAL ANALYZER
ALGORITHM
AIM:
ALGORITHM:

3
SOURCE CODE:
#include<stdio.h>
#include<graphics.h>
#include<math.h>
float round(float a);
void main()
{
int gd=DETECT,gm;
int x1,y1,x2,y2,steps,k;
float xincr,yincr,x,y,dx,dy;
printf("enter x1,y1");
scanf("%d%d",&x1,&y1);
printf("enter x2,y2");
initgraph(&gd,&gm,"c:turboc3BGI");
dx=x2-x1;
dy=y2-y1;
if(abs(dx)>abs(dy))
steps=abs(dx);
else
steps=abs(dy);
xincr=dx/steps;
yincr=dy/steps;
x=x1;
y=y1;
for(k=1;k<=steps;k++)
{
delay(100);
x+=xincr;
y+=yincr;
putpixel(round(x),round(y),WHITE);
}

4
outtextxy(200,20,"DDA");
outtextxy(x1+5,y1-5,"(x1,y1)");
outtextxy(x2+5,y2+5,"(x2,y2)");
getch();
closegraph();
}
float round(float a)
{
int b=a+0.5;
return b;
}

6
2. BRESENHAM’S LINE DRAWING
ALGORITHM
AIM:
ALGORITHM:

7
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
void main()
{
int x,y,x1,y1,x2,y2,p,dx,dy;
int gd=DETECT,gm;
initgraph(&gd,&gm,"C:TurboC3BGI");
printf("nEnter the x-coordinate of the first point ::");
scanf("%d",&x1);
printf("nEnter the y-coordinate of the first point ::");
scanf("%d",&y1);
printf("nEnter the x-coordinate of the second point ::");
scanf("%d",&x2);
printf("nEnter the y-coordinate of the second point ::");
scanf("%d",&y2);
x=x1;
y=y1;
dx=x2-x1;
dy=y2-y1;
putpixel(x,y,2);
p=(2*dy-dx);
while(x<=x2)
{
if(p<0)
{
x=x+1;
p=p+2*dy;
}

8
else
{
x=x+1;
y=y+1;
p=p+(2*dy)-(2*dx);
}
putpixel(x,y,7);
}
getch();
closegraph();
}

10
3. MIDPOINT CIRCLE DRAWING
ALGORITHM
AIM:
ALGORITHM:

11
SOURCE CODE:
#include<dos.h>
#include<stdio.h>
#include<conio.h>
void draw_circle(int,int,int);
void symmetry(int,int,int,int);
void main()
{
int xc,yc,R;
int gd=DETECT,gm;
printf("Enter the center of the circle:n");
printf("Xc =");
scanf("%d",&xc);
printf("Yc =");
scanf("%d",&yc);
printf("Enter the radius of the circle :");
scanf("%d",&R);
draw_circle(xc,yc,R);
getch();
closegraph();
}
void draw_circle(int xc,int yc,int rad)
{
int x = 0;
int y = rad;
int p = 1-rad;
symmetry(x,y,xc,yc);
for(x=0;y>x;x++)
{

12
if(p<0)
p += 2*x + 3;
else
{
p += 2*(x-y) + 5;
y--;
}
symmetry(x,y,xc,yc);
delay(50);
}
}
void symmetry(int x,int y,int xc,int yc)
{
putpixel(xc+x,yc-y,GREEN); //For pixel (x,y)
delay(50);
putpixel(xc+y,yc-x, GREEN); //For pixel (y,x)
delay(50);
putpixel(xc+y,yc+x, GREEN); //For pixel (y,-x)
delay(50);
putpixel(xc+x,yc+y, GREEN); //For pixel (x,-y)
delay(50);
putpixel(xc-x,yc+y, GREEN); //For pixel (-x,-y)
delay(50);
putpixel(xc-y,yc+x, GREEN); //For pixel (-y,-x)
delay(50);
putpixel(xc-y,yc-x, GREEN); //For pixel (-y,x)
delay(50);
putpixel(xc-x,yc-y, GREEN); //For pixel (-x,y)
delay(50);
}

14
4. CREATING VARIOUS TYPES OF
TEXTS AND FONTS
AIM:
ALGORITHM:

15
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
void main()
{
int gd=DETECT,gm,x=25,y=25,font=10;
initgraph(&gd,&gm,"C:turboC3BGI");
for(font=0;font<=4;font++)
{
settextstyle(font,HORIZ_DIR,font+1); // sets font type, font direction,
size
setcolor(font+1); // sets color for text.
outtextxy(x,y,"text with different fonts"); // prints message on screen at
(x,y)
y=y+25;
}
for(font=0;font<=2;font++)
{
settextstyle(font,VERT_DIR,font+2);
setcolor(font+1);
x=250;
y=100;
outtextxy(x,y,"text in vertical direction");
y=y+25;
}
getch();
closegraph();
}

17
5. CREATING TWO DIMENSIONAL
OBJECTS
AIM:
ALGORITHM:

18
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<dos.h>
void main()
{
int gd = DETECT, gm;
initgraph(&gd, &gm, "C:TurboC3BGI");
cleardevice();
line( 150, 100, 242, 100);
ellipse(242, 105, 0, 90, 10, 5);
line(150, 100, 120, 150);
line(252, 105, 280, 150);
line(100, 150, 320, 150);
line(100, 150, 100, 200);
line(320, 150, 320, 200);
line(100, 200, 110, 200);
line( 320, 200, 310, 200);
arc(130, 200, 0, 180, 20);
arc( 290, 200, 0, 180, 20);
line( 270, 200, 150, 200);
circle(130, 200, 17);
circle(290, 200, 17);
getch();
}

20
6. TWO-DIMENSIONAL TRANSLATION
AIM:
ALGORITHM:

21
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<math.h>
void main()
{
int gd=DETECT,gm;
int x1,y1,x2,y2,tx,ty,x3,y3,x4,y4;
printf("Enter the starting point of line segment:");
scanf("%d %d",&x1,&y1);
printf("Enter the ending point of line segment:");
scanf("%d %d",&x2,&y2);
printf("Enter translation distances tx,ty:n");
scanf("%d%d",&tx,&ty);
setcolor(5);
line(x1,y1,x2,y2);
outtextxy(x2+2,y2+2,"Original line");
x3=x1+tx;
y3=y1+ty;
x4=x2+tx;
y4=y2+ty;
setcolor(7);
line(x3,y3,x4,y4);
outtextxy(x4+2,y4+2,"Line after translation");
getch();
}

23
7. TWO- DIMENSIONAL SCALING
AIM:
ALGORITHM:

24
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<math.h>
void main()
{
int gd=DETECT,gm;
float x1,y1,x2,y2,sx,sy,x3,y3,x4,y4;
printf("Enter the starting point coordinates:");
scanf("%f %f",&x1,&y1);
printf("Enter the ending point coordinates:");
scanf("%f %f",&x2,&y2);
printf("Enter scaling factors sx,sy:n");
scanf("%f%f",&sx,&sy);
setcolor(5);
line(x1,y1,x2,y2);
x3=x1*sx;
y3=y1*sy;
x4=x2*sx;
y4=y2*sy;
setcolor(7);
line(x3,y3,x4,y4);
outtextxy(x3+2,y3+2,"Line after scaling");
getch();
}

26
8. TWO- DIMENSIONAL ROTATION
AIM:
ALGORITHM:

27
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<math.h>
void main()
{
int gd=DETECT,gm;
float x1,y1,x2,y2,x3,y3,x4,y4,a,t;
printf("Enter coordinates of starting point:n");
scanf("%f%f",&x1,&y1);
printf("Enter coordinates of ending pointn");
scanf("%f%f",&x2,&y2);
printf("Enter angle for rotationn");
scanf("%f",&a);
setcolor(5);
line(x1,y1,x2,y2);
t=a*(3.14/180);
x3=(x1*cos(t))-(y1*sin(t));
y3=(x1*sin(t))+(y1*cos(t));
x4=(x2*cos(t))-(y2*sin(t));
y4=(x2*sin(t))+(y2*cos(t));
setcolor(7);
line(x3,y3,x4,y4);
outtextxy(x3+2,y3+2,"Line after rotation");
getch();
}

29
9. THREE-DIMENSIONAL
TRANSLATION
AIM:
ALGORITHM:

30
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<math.h>
#include<process.h>
int x1,x2,y1,y2,mx,my,depth;
void draw();
void trans();
void main()
{
int gd=DETECT,gm,c;
printf("ntt3D Translationnn");
printf("nEnter 1st top value(x1,y1):");
printf("Enter right bottom value(x2,y2):");
depth=(x2-x1)/4;
mx=(x1+x2)/2;
my=(y1+y2)/2;
draw();
getch();
cleardevice();
trans();
getch();
}

31
void draw()
{
bar3d(x1,y1,x2,y2,depth,1);
}
void trans()
{
int a1,a2,b1,b2,dep,x,y;
printf("n Enter the Translation Distances:");
scanf("%d%d",&x,&y);
a1=x1+x;
a2=x2+x;
b1=y1+y;
b2=y2+y;
dep=(a2-a1)/4;
bar3d(a1,b1,a2,b2,dep,1);
setcolor(5);
draw();
}

33
10.THREE- DIMENSIONAL SCALING
AIM:
ALGORITHM:

34
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<math.h>
#include<process.h>
void draw();
void scale();
void main()
{
int gd=DETECT,gm,c;
printf("ntt3D Scalingnn");
depth=(x2-x1)/4;
mx=(x1+x2)/2;
my=(y1+y2)/2;
draw();
getch();
cleardevice();
scale();
getch();
}

35
void draw()
{
}
void scale()
{
int x,y,a1,a2,b1,b2,dep;
printf("nn Enter scaling Factors:");
scanf("%d%d",&x,&y);
a1=mx+(x1-mx)*x;
a2=mx+(x2-mx)*x;
b1=my+(y1-my)*y;
b2=my+(y2-my)*y;
dep=(a2-a1)/4;
bar3d(a1,b1,a2,b2,dep,1);
setcolor(5);
draw();
}

37
11. THREE-DIMENSIONAL ROTATION
AIM:
ALGORITHM:

38
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<math.h>
void draw();
void rotate();
void main()
{
int gd=DETECT,gm,c;
printf("n3D Transformation Rotatingnn");
depth=(x2-x1)/4;
mx=(x1+x2)/2;
my=(y1+y2)/2;
draw(); getch();
cleardevice();
rotate();
getch();
}
void draw()
{
}

39
void rotate()
{
float t;
int a1,b1,a2,b2,dep;
printf("Enter the angle to rotate=");
scanf("%f",&t);
t=t*(3.14/180);
a1=mx+(x1-mx)*cos(t)-(y1-my)*sin(t);
a2=mx+(x2-mx)*cos(t)-(y2-my)*sin(t);
b1=my+(x1-mx)*sin(t)-(y1-my)*cos(t);
b2=my+(x2-mx)*sin(t)-(y2-my)*cos(t);
if(a2>a1)
dep=(a2-a1)/4;
else
dep=(a1-a2)/4;
bar3d(a1,b1,a2,b2,dep,1); setcolor(5);
}

41
12. CURVE GENERATION
AIM:
ALGORITHM:

42
SOURCE CODE:
#include <stdio.h>
#include <stdlib.h>
#include <graphics.h>
#include <math.h>
void bezier (int x[4], int y[4])
{
int i;
double t;
initgraph (&gd, &gm, "C:TurboC3BGI");
for (t = 0.0; t < 1.0; t += 0.0005)
{
double xt = pow (1-t, 3) * x[0] + 3 * t * pow (1-t, 2) * x[1] +
3 * pow (t, 2) * (1-t) * x[2] + pow (t, 3) * x[3];
double yt = pow (1-t, 3) * y[0] + 3 * t * pow (1-t, 2) * y[1] +
3 * pow (t, 2) * (1-t) * y[2] + pow (t, 3) * y[3];
putpixel (xt, yt, WHITE);
}
for (i=0; i<4; i++)
putpixel (x[i], y[i], YELLOW);
getch();
closegraph();
return;
}

43
Void main()
{
int x[4], y[4];
int i;
printf ("Enter the x- and y-coordinates of the four control points.n");
for (i=0; i<4; i++)
scanf ("%d%d", &x[i], &y[i]);
bezier (x, y);
}

45
13. MOVING CIRCLE IN DIFFERENT
DIRECTIONS
AIM:
ALGORITHM:

46
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<dos.h>
void main()
{
int gd=DETECT,gm,i;
//for moving circle from left to right,the following loop works
for(i=50;i<=getmaxx();i++)
{
setcolor(3);
setfillstyle(SOLID_FILL,9);
circle(50+i,50,50);
floodfill(52+i,52,3);
delay(20);
cleardevice();
}
//for moving circle from right to left, the following loop works
for(i=getmaxy();i>=0;i--)
{
setcolor(3);
circle(i,50,50);
floodfill(i+2,52,3);
delay(20);
cleardevice();
}
//for moving circle from top to bottom,the following loop works

47
for(i=50;i<=getmaxy();i++)
{
setcolor(3);
circle(50,i,50);
floodfill(52,i+2,3);
delay(20);
cleardevice();
}
//for moving circle from bottom to top,the following loop works
for(i=getmaxy();i>=0;i--)
{
setcolor(3);
circle(50,i,50);
floodfill(52,i+2,3);
delay(20);
cleardevice();
}
//for moving circle in diagonal direction,the following loop works
for(i=50;i<=getmaxx();i++)
{
setcolor(3);
circle(i,i,50);
floodfill(i+2,i+2,3);
delay(20);
cleardevice();
}

48
//for moving circle in reverse diagonal direction,the following loop
works
for(i=getmaxx();i>=0;i--)
{
setcolor(3);
circle(i,i,50);
floodfill(i+2,i+2,3);
delay(20);
cleardevice();
}
getch();
}

50
14. MAN WALKING USING SIMPLE
ANIMATION
AIM:
ALGORITHM:

51
SOURCE CODE:
#include<stdio.h>
#include<dos.h>
#include<conio.h>
#include<stdlib.h>
void main()
{
int gd = DETECT, gm = DETECT, c = -200, i = 0, x = 40, l = 15, h =
15, ht = 0;
cleardevice();
setcolor(BROWN);
line(0, 201, 600, 201);
cont:
while (!kbhit()) {
setcolor(4);
ellipse(x, 100, 0, 180, 50, 30);
line(x - 50, 100, x + 50, 100);
line(x, 100, x, 150);
circle(x - 20, 115, 15);
line(x - 20, 130, x - 20, 175);
line(x - 20, 175, x - 20 - l, 200);
line(x - 20, 175, x - 20 + l, 200);
line(x - 20, 140, x, 150);
line(x - 20, 140, x - 20 - h, 160);
setcolor(0);
delay(50);
ellipse(x, 100, 0, 180, 50, 30);
line(x - 50, 100, x + 50, 100);
line(x, 100, x, 150);
circle(x - 20, 115, 15);

52
line(x - 20, 130, x - 20, 175);
line(x - 20, 175, x - 20 - l, 200);
line(x - 20, 175, x - 20 + l, 200);
line(x - 20, 140, x, 150);
line(x - 20, 140, x - 20 - h, 160);
line(x + 50, 100, x + 50, 200);
x++;
l--;
if (l == -15)
l = 15;
if (ht == 1)
h++;
else
h--;
if (h == 15)
ht = 0;
else if (h == -15)
ht = 1;
}
if (getch() == ' ') {
while (!kbhit());
getch();
goto cont;
}
}

54
15 .a COLORING THE OBJECT USING
4-CONNECTED FLOODFILL
AIM:
ALGORITHM:

55
SOURCE CODE:
#include<stdio.h>
#include<conio.h>
#include<dos.h>
void flood(int,int,int,int);
void main()
{
int gd,gm=DETECT;
clrscr();
detectgraph(&gd,&gm);
rectangle(50,50,100,100);
flood(55,55,9,0);
getch();
}
void flood(int x,int y, int fill_col, int old_col)
{
if(getpixel(x,y)==old_col)
{
delay(10);
putpixel(x,y,fill_col);
flood(x+1,y,fill_col,old_col);
flood(x-1,y,fill_col,old_col);
flood(x,y+1,fill_col,old_col);
flood(x,y-1,fill_col,old_col);
}
}

57
15. b COLORING THE OBJECT
USING FLOODFILL FUNCTION
AIM:
ALGORITHM:

58
SOURCE CODE:
#include<conio.h>
main()
{
setcolor(RED);
circle(100,100,50);
floodfill(100,100,RED);
getch();
closegraph();
return 0;
}

Computer graphics lab manual

More Related Content

What's hot

Similar to Computer graphics lab manual

More from Uma mohan

Recently uploaded

Computer graphics lab manual