1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License, Version 1.0 only 6 * (the "License"). You may not use this file except in compliance 7 * with the License. 8 * 9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 10 * or http://www.opensolaris.org/os/licensing. 11 * See the License for the specific language governing permissions 12 * and limitations under the License. 13 * 14 * When distributing Covered Code, include this CDDL HEADER in each 15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 16 * If applicable, add the following below this CDDL HEADER, with the 17 * fields enclosed by brackets "[]" replaced with your own identifying 18 * information: Portions Copyright [yyyy] [name of copyright owner] 19 * 20 * CDDL HEADER END 21 */ 22 /* 23 * Copyright 1989 Sun Microsystems, Inc. All rights reserved. 24 * Use is subject to license terms. 25 */ 26 27 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 28 /* All Rights Reserved */ 29 30 /* 31 * University Copyright- Copyright (c) 1982, 1986, 1988 32 * The Regents of the University of California 33 * All Rights Reserved 34 * 35 * University Acknowledgment- Portions of this document are derived from 36 * software developed by the University of California, Berkeley, and its 37 * contributors. 38 */ 39 40 #include <stdio.h> 41 #include <math.h> 42 #define PI 3.141592654 43 #define hmot(n) hpos += n 44 #define hgoto(n) hpos = n 45 #define vmot(n) vgoto(vpos + n) 46 47 extern int hpos; 48 extern int vpos; 49 extern int size; 50 extern short *pstab; 51 extern int DX; /* step size in x */ 52 extern int DY; /* step size in y */ 53 extern int drawdot; /* character to use when drawing */ 54 extern int drawsize; /* shrink point size by this facter */ 55 56 int maxdots = 32000; /* maximum number of dots in an object */ 57 58 #define sgn(n) ((n > 0) ? 1 : ((n < 0) ? -1 : 0)) 59 #define abs(n) ((n) >= 0 ? (n) : -(n)) 60 #define max(x,y) ((x) > (y) ? (x) : (y)) 61 #define min(x,y) ((x) < (y) ? (x) : (y)) 62 #define arcmove(x,y) { hgoto(x); vmot(-vpos-(y)); } 63 64 /* draw line from here to dx, dy using s */ 65 int 66 drawline(int dx, int dy, char *s) 67 { 68 int xd, yd; 69 float val, slope; 70 int i, numdots; 71 int dirmot, perp; 72 int motincr, perpincr; 73 int ohpos, ovpos, osize, ofont; 74 float incrway; 75 76 int itemp; /*temp. storage for value returned byint function sgn*/ 77 osize = size; 78 setsize(t_size(pstab[osize-1] / drawsize)); 79 ohpos = hpos; 80 ovpos = vpos; 81 xd = dx / DX; 82 yd = dy / DX; 83 if (xd == 0) { 84 numdots = abs (yd); 85 numdots = min(numdots, maxdots); 86 motincr = DX * sgn (yd); 87 for (i = 0; i < numdots; i++) { 88 vmot(motincr); 89 put1(drawdot); 90 } 91 vgoto(ovpos + dy); 92 setsize(osize); 93 return (0); 94 } 95 if (yd == 0) { 96 numdots = abs (xd); 97 motincr = DX * sgn (xd); 98 for (i = 0; i < numdots; i++) { 99 hmot(motincr); 100 put1(drawdot); 101 } 102 hgoto(ohpos + dx); 103 setsize(osize); 104 return (0); 105 } 106 if (abs (xd) > abs (yd)) { 107 val = slope = (float) xd/yd; 108 numdots = abs (xd); 109 numdots = min(numdots, maxdots); 110 dirmot = 'h'; 111 perp = 'v'; 112 motincr = DX * sgn (xd); 113 perpincr = DX * sgn (yd); 114 } 115 else { 116 val = slope = (float) yd/xd; 117 numdots = abs (yd); 118 numdots = min(numdots, maxdots); 119 dirmot = 'v'; 120 perp = 'h'; 121 motincr = DX * sgn (yd); 122 perpincr = DX * sgn (xd); 123 } 124 incrway = itemp = sgn ((int) slope); 125 for (i = 0; i < numdots; i++) { 126 val -= incrway; 127 if (dirmot == 'h') 128 hmot(motincr); 129 else 130 vmot(motincr); 131 if (val * slope < 0) { 132 if (perp == 'h') 133 hmot(perpincr); 134 else 135 vmot(perpincr); 136 val += slope; 137 } 138 put1(drawdot); 139 } 140 hgoto(ohpos + dx); 141 vgoto(ovpos + dy); 142 setsize(osize); 143 144 return (0); 145 } 146 147 int 148 drawwig(char *s) /* draw wiggly line */ 149 { 150 int x[50], y[50], xp, yp, pxp, pyp; 151 float t1, t2, t3, w; 152 int i, j, numdots, N; 153 int osize, ofont; 154 char temp[50], *p, *getstr(); 155 156 osize = size; 157 setsize(t_size(pstab[osize-1] / drawsize)); 158 p = s; 159 for (N = 2; (p=getstr(p,temp)) != NULL && N < sizeof(x)/sizeof(x[0]); N++) { 160 x[N] = atoi(temp); 161 p = getstr(p, temp); 162 y[N] = atoi(temp); 163 } 164 x[0] = x[1] = hpos; 165 y[0] = y[1] = vpos; 166 for (i = 1; i < N; i++) { 167 x[i+1] += x[i]; 168 y[i+1] += y[i]; 169 } 170 x[N] = x[N-1]; 171 y[N] = y[N-1]; 172 pxp = pyp = -9999; 173 for (i = 0; i < N-1; i++) { /* interval */ 174 numdots = (dist(x[i],y[i], x[i+1],y[i+1]) + dist(x[i+1],y[i+1], x[i+2],y[i+2])) / 2; 175 numdots /= DX; 176 numdots = min(numdots, maxdots); 177 for (j = 0; j < numdots; j++) { /* points within */ 178 w = (float) j / numdots; 179 t1 = 0.5 * w * w; 180 w = w - 0.5; 181 t2 = 0.75 - w * w; 182 w = w - 0.5; 183 t3 = 0.5 * w * w; 184 xp = t1 * x[i+2] + t2 * x[i+1] + t3 * x[i] + 0.5; 185 yp = t1 * y[i+2] + t2 * y[i+1] + t3 * y[i] + 0.5; 186 if (xp != pxp || yp != pyp) { 187 hgoto(xp); 188 vgoto(yp); 189 put1(drawdot); 190 pxp = xp; 191 pyp = yp; 192 } 193 } 194 } 195 setsize(osize); 196 197 return (0); 198 } 199 200 /* copy next non-blank string from p to temp, update p */ 201 char *getstr(char *p, char *temp) 202 { 203 while (*p == ' ' || *p == '\t' || *p == '\n') 204 p++; 205 if (*p == '\0') { 206 temp[0] = 0; 207 return(NULL); 208 } 209 while (*p != ' ' && *p != '\t' && *p != '\n' && *p != '\0') 210 *temp++ = *p++; 211 *temp = '\0'; 212 return(p); 213 } 214 215 int 216 drawcirc(int d) 217 { 218 int xc, yc; 219 220 xc = hpos; 221 yc = vpos; 222 conicarc(hpos + d/2, -vpos, hpos, -vpos, hpos, -vpos, d/2, d/2); 223 hgoto(xc + d); /* circle goes to right side */ 224 vgoto(yc); 225 226 return (0); 227 } 228 229 /* integer distance from x1,y1 to x2,y2 */ 230 int 231 dist(int x1, int y1, int x2, int y2) 232 { 233 float dx, dy; 234 235 dx = x2 - x1; 236 dy = y2 - y1; 237 return sqrt(dx*dx + dy*dy) + 0.5; 238 } 239 240 int 241 drawarc(int dx1, int dy1, int dx2, int dy2) 242 { 243 int x0, y0, x2, y2, r; 244 245 x0 = hpos + dx1; /* center */ 246 y0 = vpos + dy1; 247 x2 = x0 + dx2; /* "to" */ 248 y2 = y0 + dy2; 249 r = sqrt((float) dx1 * dx1 + (float) dy1 * dy1) + 0.5; 250 conicarc(x0, -y0, hpos, -vpos, x2, -y2, r, r); 251 252 return (0); 253 } 254 255 int 256 drawellip(int a, int b) 257 { 258 int xc, yc; 259 260 xc = hpos; 261 yc = vpos; 262 conicarc(hpos + a/2, -vpos, hpos, -vpos, hpos, -vpos, a/2, b/2); 263 hgoto(xc + a); 264 vgoto(yc); 265 266 return (0); 267 } 268 269 #define sqr(x) (long int)(x)*(x) 270 271 int 272 conicarc(int x, int y, int x0, int y0, int x1, int y1, int a, int b) 273 { 274 /* based on Bresenham, CACM, Feb 77, pp 102-3 */ 275 /* by Chris Van Wyk */ 276 /* capitalized vars are an internal reference frame */ 277 long dotcount = 0; 278 int osize, ofont; 279 int xs, ys, xt, yt, Xs, Ys, qs, Xt, Yt, qt, 280 M1x, M1y, M2x, M2y, M3x, M3y, 281 Q, move, Xc, Yc; 282 int ox1, oy1; 283 long delta; 284 float xc, yc; 285 float radius, slope; 286 float xstep, ystep; 287 288 osize = size; 289 setsize(t_size(pstab[osize-1] / drawsize)); 290 ox1 = x1; 291 oy1 = y1; 292 if (a != b) /* an arc of an ellipse; internally, will still think of circle */ 293 if (a > b) { 294 xstep = (float)a / b; 295 ystep = 1; 296 radius = b; 297 } else { 298 xstep = 1; 299 ystep = (float)b / a; 300 radius = a; 301 } 302 else { /* a circular arc; radius is computed from center and first point */ 303 xstep = ystep = 1; 304 radius = sqrt((float)(sqr(x0 - x) + sqr(y0 - y))); 305 } 306 307 308 xc = x0; 309 yc = y0; 310 /* now, use start and end point locations to figure out 311 the angle at which start and end happen; use these 312 angles with known radius to figure out where start 313 and end should be 314 */ 315 slope = atan2((double)(y0 - y), (double)(x0 - x) ); 316 if (slope == 0.0 && x0 < x) 317 slope = 3.14159265; 318 x0 = x + radius * cos(slope) + 0.5; 319 y0 = y + radius * sin(slope) + 0.5; 320 slope = atan2((double)(y1 - y), (double)(x1 - x)); 321 if (slope == 0.0 && x1 < x) 322 slope = 3.14159265; 323 x1 = x + radius * cos(slope) + 0.5; 324 y1 = y + radius * sin(slope) + 0.5; 325 /* step 2: translate to zero-centered circle */ 326 xs = x0 - x; 327 ys = y0 - y; 328 xt = x1 - x; 329 yt = y1 - y; 330 /* step 3: normalize to first quadrant */ 331 if (xs < 0) 332 if (ys < 0) { 333 Xs = abs(ys); 334 Ys = abs(xs); 335 qs = 3; 336 M1x = 0; 337 M1y = -1; 338 M2x = 1; 339 M2y = -1; 340 M3x = 1; 341 M3y = 0; 342 } else { 343 Xs = abs(xs); 344 Ys = abs(ys); 345 qs = 2; 346 M1x = -1; 347 M1y = 0; 348 M2x = -1; 349 M2y = -1; 350 M3x = 0; 351 M3y = -1; 352 } 353 else if (ys < 0) { 354 Xs = abs(xs); 355 Ys = abs(ys); 356 qs = 0; 357 M1x = 1; 358 M1y = 0; 359 M2x = 1; 360 M2y = 1; 361 M3x = 0; 362 M3y = 1; 363 } else { 364 Xs = abs(ys); 365 Ys = abs(xs); 366 qs = 1; 367 M1x = 0; 368 M1y = 1; 369 M2x = -1; 370 M2y = 1; 371 M3x = -1; 372 M3y = 0; 373 } 374 375 376 Xc = Xs; 377 Yc = Ys; 378 if (xt < 0) 379 if (yt < 0) { 380 Xt = abs(yt); 381 Yt = abs(xt); 382 qt = 3; 383 } else { 384 Xt = abs(xt); 385 Yt = abs(yt); 386 qt = 2; 387 } 388 else if (yt < 0) { 389 Xt = abs(xt); 390 Yt = abs(yt); 391 qt = 0; 392 } else { 393 Xt = abs(yt); 394 Yt = abs(xt); 395 qt = 1; 396 } 397 398 399 /* step 4: calculate number of quadrant crossings */ 400 if (((4 + qt - qs) 401 % 4 == 0) 402 && (Xt <= Xs) 403 && (Yt >= Ys) 404 ) 405 Q = 3; 406 else 407 Q = (4 + qt - qs) % 4 - 1; 408 /* step 5: calculate initial decision difference */ 409 delta = sqr(Xs + 1) 410 + sqr(Ys - 1) 411 -sqr(xs) 412 -sqr(ys); 413 /* here begins the work of drawing 414 we hope it ends here too */ 415 while ((Q >= 0) 416 || ((Q > -2) 417 && ((Xt > Xc) 418 && (Yt < Yc) 419 ) 420 ) 421 ) { 422 if (dotcount++ % DX == 0) 423 putdot((int)xc, (int)yc); 424 if (Yc < 0.5) { 425 /* reinitialize */ 426 Xs = Xc = 0; 427 Ys = Yc = sqrt((float)(sqr(xs) + sqr(ys))); 428 delta = sqr(Xs + 1) + sqr(Ys - 1) - sqr(xs) - sqr(ys); 429 Q--; 430 M1x = M3x; 431 M1y = M3y; 432 { 433 int T; 434 T = M2y; 435 M2y = M2x; 436 M2x = -T; 437 T = M3y; 438 M3y = M3x; 439 M3x = -T; 440 } 441 } else { 442 if (delta <= 0) 443 if (2 * delta + 2 * Yc - 1 <= 0) 444 move = 1; 445 else 446 move = 2; 447 else if (2 * delta - 2 * Xc - 1 <= 0) 448 move = 2; 449 else 450 move = 3; 451 switch (move) { 452 case 1: 453 Xc++; 454 delta += 2 * Xc + 1; 455 xc += M1x * xstep; 456 yc += M1y * ystep; 457 break; 458 case 2: 459 Xc++; 460 Yc--; 461 delta += 2 * Xc - 2 * Yc + 2; 462 xc += M2x * xstep; 463 yc += M2y * ystep; 464 break; 465 case 3: 466 Yc--; 467 delta -= 2 * Yc + 1; 468 xc += M3x * xstep; 469 yc += M3y * ystep; 470 break; 471 } 472 } 473 } 474 475 476 setsize(osize); 477 drawline((int)xc-ox1,(int)yc-oy1,"."); 478 479 return (0); 480 } 481 482 int 483 putdot(int x, int y) 484 { 485 arcmove(x, y); 486 put1(drawdot); 487 488 return (0); 489 } 490