1. Theory :
2. https://pastebin.pl/view/d9b1d994
3.  
4. // EXP 1 To implement DDA Algorithm for drawing a line segment between two given end
5.  
6. #include<stdio.h>
7. #include<graphics.h>
8. #include<math.h>
9. void main()
10. {
11. float x,y,x1,y1,x2,y2,dx,dy,length;
12. int i,gd,gm; clrscr();
13. /* Read two end points of line --
14. -------------------------------- */
15. printf("Enter the value of x1
16. :\t"); scanf("%f",&x1);
17. printf("Enter the value of y1
18. :\t"); scanf("%f",&y1);
19. printf("Enter the value of x2
20. :\t"); scanf("%f",&x2);
21. printf("Enter the value of y2
22. :\t"); scanf("%f",&y2);
23. /* Initialise graphics mode ----------------------------------
24. */
25. detectgraph(&gd,&gm);
26. initgraph(&gd,&gm,"\\tc\\BGI");
27. dx=abs(x2-x1); dy=abs(y2-y1);
28. if (dx >= dy)
29. { length = dx; }
30. else
31. { length = dy; } dx =
32. (x2-x1)/length; dy =
33. (y2-y1)/length; x =
34. x1 + 0.5; /* Factor
35. 0.5 is added to
36. round the values */
37. y = y1 + 0.5; /*
38. Factor 0.5 is added
39. to round the values
40. */ putpixel (x, y,
41. 15); i = 1; /*
42. Initialise loop
43. counter */ while(i
44. <= length)
45. {
46. x = x + dx;
47. y = y + dy;putpixel (x, y, 15); i = i + 1; delay(100); /*Delay is purposely
48. inserted to see observe the line drawing
49. process*/
50. }
51. getch();
52. closegraph();
53. }
54.  
55. // To implement Bresenham’s line drawing algorithm for drawing a line segment between
56. two given endpoints A (x1, y2) and B(x2, y2).
57.  
58. #include<stdio.h>
59. #include<graphics.h>
60. #include<math.h>
61. #include<conio.h>
62. void main()
63. {
64. float x,y,x1,y1,x2,y2,dx,dy,e;
65. int i,gd,gm; clrscr();
66. /* Read two end points of line --
67. -------------------------------- */
68. printf("Enter the value of x1
69. :\t"); scanf("%f",&x1);
70. printf("Enter the value of y1
71. :\t"); scanf("%f",&y1);
72. printf("Enter the value of x2
73. :\t"); scanf("%f",&x2);
74. printf("Enter the value of y2
75. :\t"); scanf("%f",&y2);
76. /* Initialise graphics mode ----------------------------------
77. */
78. detectgraph(&gd,&gm);
79. initgraph(&gd,&gm,"c:\\tc\\BGI");
80. dx=abs(x2-x1); dy=abs(y2-y1);
81. /* Initialise starting point
82. -----------------------------*/
83. x = x1; y = y1; putpixel (x,
84. y, 15) ;
85. /* Initialise decision variable
86. -------------------------------- */ e
87. = 2 * dy-dx;
88. i = 1; /* Initialise loop counter */ do
89. { while(e >= 0)
90. {
91. y = y + 1; e =
92. e - 2 * dx; }
93. x = x + 1; e = e + 2
94. * dy; i = i + 1; putpixel (x,
95.  
96. y, 15); }while( i <= dx);
97. getch(); closegraph();
98. }
99.  
100.  
101. // To implement area filling algorithm.
102.  
103. #include<stdio.h>
104. #include<graphics.h>
105. #include<conio.h>
106. void flood(int, int, int, int);
107. void main()
108. { int gd,gm;
109. /* Initialise graphics mode---------------------------------- */
110. detectgraph(&gd,&gm);
111. initgraph(&gd,&gm,"\\tc\\bgi");
112. rectangle(50,50,100,100)
113. ; flood(55,55,4,15);
114. getch();
115. closegraph();
116. }
117. void flood(int seed_x,int seed_y,int foreground_col,int background_col)
118. { if(getpixel(seed_x,seed_y)!= background_col && getpixel(seed_x,seed_y)!=
119. foreground_col)
120. { putpixel(seed_x,seed_y,foreground_col);
121. flood(seed_x+1,seed_y,foreground_col,background_col);
122. flood(seed_x-1,seed_y,foreground_col,background_col);
123. flood(seed_x,seed_y+1,foreground_col,background_col);
124. flood(seed_x,seed_y-1,foreground_col,background_col);
125. flood(seed_x+1,seed_y+1,foreground_col,background_col);
126. flood(seed_x-1,seed_y-1,foreground_col,background_col);
127. flood(seed_x+1,seed_y-1,foreground_col,background_col);
128. flood(seed_x-1,seed_y+1,foreground_col,background_col); }
129. }
130.  
131. //To implement Bit Map method for given character generation
132.  
133. #include<stdio.h>
134. #include<conio.h>
135. #include<graphics.h>
136. void main()
137. { int gd=DETECT,gm,i,j; int
138. a[20][20]=
139. {{0,0,0,1,1,1,0,0,0,0,0,0,0,0,1,1,1,1,0,0},
140. {0,0,1,0,0,0,1,0,0,0,0,0,0,1,0,0,0,0,1,0},
141. {0,1,0,0,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,1},
142. {1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0},
143. {1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0},
144. {1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,1,1,1,0},
145. {1,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1,0},
146. {0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,1,0},
147. {0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,1,0,0},
148. {0,0,0,1,1,1,0,0,0,0,0,0,0,1,1,1,1,0,0,0}};
149. initgraph(&gd,&gm,"c:\\tc\\bgi");
150. for(i=0;i<19;i++)
151. { for(j=0;j<19;j++)
152. {
153. if(a[i][j]==1)
154.  putpixel(100+j,200+i,WHITE);
155. }
156. }
157. getch();
158. }
159.  
160.  
161. //: To apply the basic 2D transformations such as translation, Scaling, Rotation for a
162. given 2D object
163.  
164. include<graphics.h>
165. #include<conio.h>
166. #include<math.h>
167. #include<stdio.h>
168. int main()
169. {
170. int i, x, y, tx, ty, sx, sy, angle=10, xmax, ymax, xmid, ymid, op;
171. int gd,gm; float p1[10]={50,50,
172.  100,50,
173.  100,100,
174.  50,100,
175.  50,50,};
176. int pi[10]; float
177. b[3][3]={1,0,0,
178.  0,1,0,
179.  0,0,1}; int c[1][1]; float
180. a[1][1]; printf("\nSelect the transformation
181. : "); printf("\n1 : Traslation"); printf("\n2 :
182. Rotation"); printf("\n3 : Scaling");
183. printf("\n4 : Rotation about arbitrary
184. point"); printf( "\nEnter the option : ");
185. scanf("%d",&op); switch(op)
186. {
187. case 1:
188. printf("\nEnter x traslation : ");
189. scanf("%d",&tx);
190. printf("\nEnter y traslation : ");
191. scanf("%d",&ty);
192. b[0][0] = 1;
193. b[0][1] = 0;
194. b[0][2] = 0;
195. b[1][0] = 0;
196. b[1][1] = 1;
197. b[1][2] = 0;
198. b[2][0] = tx;
199. b[2][1] = ty;
200. b[2][2] = 1;
201. break;
202. case 2:
203. printf("\nEnter Rotation angle : ");
204. scanf("%d",&angle);
205. b[0][0] =cos(angle*3.142/180);
206. b[0][1] =sin(angle*3.142/180);
207. b[0][2] = 0;
208. b[1][0] =-sin(angle*3.142/180);
209. b[1][1] = cos(angle*3.142/180);
210. b[1][2] = 0;
211. b[2][0] = 0;
212. b[2][1] = 0;
213. b[2][2] = 1;
214. break;
215. case 3:
216. printf("\nEnter x scaling : ");
217. scanf("%d",&sx);
218. printf("\nEnter y scaling : ");
219. scanf("%d",&sy);
220. b[0][0] = sx;
221. b[0][1] = 0;
222. b[0][2] = 0;
223. b[1][0] = 0;
224. b[1][1] = sy;
225. b[1][2] = 0;
226. b[2][0] = 0;
227. b[2][1] = 0;
228. b[2][2] = 1;
229. break;
230.  
231. case 4:
232. printf("\nEnter x coordinate of arbitrary point :
233. "); scanf("%d",&x); printf("\nEnter y coordinate
234. of arbitrary point : "); scanf("%d",&y);
235. printf("\nEnter Rotation angle : ");
236. scanf("%d",&angle);
237. tx = x;
238. ty = y;
239. b[0][0]
240. =cos(an
241. gle*3.1
242. 42/180)
243. ; b[0][1]
244. =sin(an
245. gle*3.1
246. 42/180)
247. ; b[0][2]
248. = 0;
249. b[1][0] =-sin(angle*3.142/180);
250. b[1][1] = cos(angle*3.142/180);
251. b[1][2] = 0;
252. b[2][0] = -tx* cos(angle*3.142/180) + ty*sin(angle*3.142/180)+tx;
253. b[2][1] = -tx* sin(angle*3.142/180) - ty*cos(angle*3.142/180)+ty;
254. b[2][2] = 1;
255. } detectgraph(&gd,&gm);
256. initgraph(&gd,&gm,"\\tc\\bgi"); // Initialize
257. graphics
258. xmax = getmaxx(); // Get maximum x
259. coordinate
260. ymax = getmaxy(); // Get maximum y
261. coordinate
262. xmid = xmax/2; // Get the center x
263. coordinate
264.  
265. ymid = ymax/2;
266. setcolor(1);
267. // Get the center y
268. coordinate
269. line(xmid,0,xmid,ymax); // Draw y coordinate
270. line(0, ymid, xmax, ymid); // Draw x coordinate
271. setcolor(4); for
272. (i=0; i<8;i=i+2)
273. { line(p1[i]+xmid,ymid-p1[i+1],xmid+p1[i+2],ymid-p1[i+3]);
274. }
275. for(i=0;i<9;i=i+2)
276. {
277. a[0][0]=p1[i]; a[0][1]=p1[i+1]; c[0][0] =
278. a[0][0]*b[0][0]+a[0][1]*b[1][0]+b[2][0]; c[0][1] =
279. a[0][0]*b[0][1]+a[0][1]*b[1][1]+b[2][1];
280. pi[i]=c[0][0]; pi[i+1]=c[0][1];
281. }
282. setcolor(15); for
283. (i=0; i<8;i=i+2)
284. { line(xmid+pi[i],ymid-pi[i+1],xmid+pi[i+2],ymid-pi[i+3]);
285. }
286. getch();
287. closegraph();
288. return 0;
289. }
290.  
291. // To implement Bezier curve.
292.  
293. #include <stdio.h>
294. #include <graphics.h>
295. #include <conio.h>
296. #include<stdio.h>
297. #include<process.h>
298. int gd,gm,maxx,maxy;
299. float xxx[4][2];
300. /* Function to draw line from relative position specified in array xxx-----------------------*/
301. void line1(float x2,float y2)
302. { line(xxx[0][0],xxx[0][1],x2,y2);
303. xxx[0][0]=x2; xxx[0][1]=y2;
304. }
305. /* Bezier function-------------------- */
306. void bezier(float xb,float yb,float xc,float yc,float xd,float yd,int n)
307. { float xab,yab,xbc,ybc,xcd,ycd;
308. float xabc,yabc,xbcd,ybcd;
309. float xabcd,yabcd;
310. if (n==0)
311. {
312. line1(xb,yb);
313. line1(xc,yc);
314. line1(xd,yd); }
315. else
316. { xab = (xxx[0][0]+xb)/2; yab =
317. (xxx[0][1]+yb)/2; xbc = (xb+xc)/2; ybc =
318. (yb+yc)/2; xcd = (xc+xd)/2; ycd =
319. (yc+yd)/2; xabc = (xab+xbc)/2; yabc =
320. (yab+ybc)/2; xbcd = (xbc+xcd)/2; ybcd =
321. (ybc+ycd)/2; xabcd = (xabc+xbcd)/2;
322. yabcd = (yabc+ybcd)/2; n=n-1;
323. bezier(xab,yab,xabc,yabc,xabcd,yabcd,n);
324. bezier(xbcd,ybcd,xcd,ycd,xd,yd,n);
325. }
326. }
327. /* Function to initialise graphics----------------------------------- */ void
328. igraph()
329. { detectgraph(&gd,&gm);
330. if(gd<0)
331. { puts("CANNOT DETECT A GRAPHICS CARD");
332. exit(1);
333. }
334. initgraph(&gd,&gm,"\\tc\\bgi");
335. } void
336. main()
337. {
338. int i;
339. float temp1,temp2;
340. igraph();
341. /*Read two end points and two control points of the curve*/
342. for(i=0;i<4;i++)
343. {
344. printf("Enter (x,y) coordinates of point%d : ",i+1);
345. scanf("%f,%f",&temp1,&temp2);
346. xxx[i][0] = temp1; xxx[i][1]
347. = temp2;
348. }
349. bezier(xxx[1][0],xxx[1][1],xxx[2][0],xxx[2][1],xxx[3][0],xxx[3][1],8); getch();
350. closegraph();
351. }
352.