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 #pragma ident "%Z%%M% %I% %E% SMI" 41 42 #include <stdio.h> 43 #include <math.h> 44 #define PI 3.141592654 45 #define hmot(n) hpos += n 46 #define hgoto(n) hpos = n 47 #define vmot(n) vgoto(vpos + n) 48 49 extern int hpos; 50 extern int vpos; 51 extern int size; 52 extern short *pstab; 53 extern int DX; /* step size in x */ 54 extern int DY; /* step size in y */ 55 extern int drawdot; /* character to use when drawing */ 56 extern int drawsize; /* shrink point size by this facter */ 57 58 int maxdots = 32000; /* maximum number of dots in an object */ 59 60 #define sgn(n) ((n > 0) ? 1 : ((n < 0) ? -1 : 0)) 61 #define abs(n) ((n) >= 0 ? (n) : -(n)) 62 #define max(x,y) ((x) > (y) ? (x) : (y)) 63 #define min(x,y) ((x) < (y) ? (x) : (y)) 64 #define arcmove(x,y) { hgoto(x); vmot(-vpos-(y)); } 65 66 int 67 drawline(dx, dy, s) /* draw line from here to dx, dy using s */ 68 int dx, dy; 69 char *s; 70 { 71 int xd, yd; 72 float val, slope; 73 int i, numdots; 74 int dirmot, perp; 75 int motincr, perpincr; 76 int ohpos, ovpos, osize, ofont; 77 float incrway; 78 79 int itemp; /*temp. storage for value returned byint function sgn*/ 80 osize = size; 81 setsize(t_size(pstab[osize-1] / drawsize)); 82 ohpos = hpos; 83 ovpos = vpos; 84 xd = dx / DX; 85 yd = dy / DX; 86 if (xd == 0) { 87 numdots = abs (yd); 88 numdots = min(numdots, maxdots); 89 motincr = DX * sgn (yd); 90 for (i = 0; i < numdots; i++) { 91 vmot(motincr); 92 put1(drawdot); 93 } 94 vgoto(ovpos + dy); 95 setsize(osize); 96 return (0); 97 } 98 if (yd == 0) { 99 numdots = abs (xd); 100 motincr = DX * sgn (xd); 101 for (i = 0; i < numdots; i++) { 102 hmot(motincr); 103 put1(drawdot); 104 } 105 hgoto(ohpos + dx); 106 setsize(osize); 107 return (0); 108 } 109 if (abs (xd) > abs (yd)) { 110 val = slope = (float) xd/yd; 111 numdots = abs (xd); 112 numdots = min(numdots, maxdots); 113 dirmot = 'h'; 114 perp = 'v'; 115 motincr = DX * sgn (xd); 116 perpincr = DX * sgn (yd); 117 } 118 else { 119 val = slope = (float) yd/xd; 120 numdots = abs (yd); 121 numdots = min(numdots, maxdots); 122 dirmot = 'v'; 123 perp = 'h'; 124 motincr = DX * sgn (yd); 125 perpincr = DX * sgn (xd); 126 } 127 incrway = itemp = sgn ((int) slope); 128 for (i = 0; i < numdots; i++) { 129 val -= incrway; 130 if (dirmot == 'h') 131 hmot(motincr); 132 else 133 vmot(motincr); 134 if (val * slope < 0) { 135 if (perp == 'h') 136 hmot(perpincr); 137 else 138 vmot(perpincr); 139 val += slope; 140 } 141 put1(drawdot); 142 } 143 hgoto(ohpos + dx); 144 vgoto(ovpos + dy); 145 setsize(osize); 146 147 return (0); 148 } 149 150 int 151 drawwig(s) /* draw wiggly line */ 152 char *s; 153 { 154 int x[50], y[50], xp, yp, pxp, pyp; 155 float t1, t2, t3, w; 156 int i, j, numdots, N; 157 int osize, ofont; 158 char temp[50], *p, *getstr(); 159 160 osize = size; 161 setsize(t_size(pstab[osize-1] / drawsize)); 162 p = s; 163 for (N = 2; (p=getstr(p,temp)) != NULL && N < sizeof(x)/sizeof(x[0]); N++) { 164 x[N] = atoi(temp); 165 p = getstr(p, temp); 166 y[N] = atoi(temp); 167 } 168 x[0] = x[1] = hpos; 169 y[0] = y[1] = vpos; 170 for (i = 1; i < N; i++) { 171 x[i+1] += x[i]; 172 y[i+1] += y[i]; 173 } 174 x[N] = x[N-1]; 175 y[N] = y[N-1]; 176 pxp = pyp = -9999; 177 for (i = 0; i < N-1; i++) { /* interval */ 178 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; 179 numdots /= DX; 180 numdots = min(numdots, maxdots); 181 for (j = 0; j < numdots; j++) { /* points within */ 182 w = (float) j / numdots; 183 t1 = 0.5 * w * w; 184 w = w - 0.5; 185 t2 = 0.75 - w * w; 186 w = w - 0.5; 187 t3 = 0.5 * w * w; 188 xp = t1 * x[i+2] + t2 * x[i+1] + t3 * x[i] + 0.5; 189 yp = t1 * y[i+2] + t2 * y[i+1] + t3 * y[i] + 0.5; 190 if (xp != pxp || yp != pyp) { 191 hgoto(xp); 192 vgoto(yp); 193 put1(drawdot); 194 pxp = xp; 195 pyp = yp; 196 } 197 } 198 } 199 setsize(osize); 200 201 return (0); 202 } 203 204 char *getstr(p, temp) /* copy next non-blank string from p to temp, update p */ 205 char *p, *temp; 206 { 207 while (*p == ' ' || *p == '\t' || *p == '\n') 208 p++; 209 if (*p == '\0') { 210 temp[0] = 0; 211 return(NULL); 212 } 213 while (*p != ' ' && *p != '\t' && *p != '\n' && *p != '\0') 214 *temp++ = *p++; 215 *temp = '\0'; 216 return(p); 217 } 218 219 int 220 drawcirc(d) 221 { 222 int xc, yc; 223 224 xc = hpos; 225 yc = vpos; 226 conicarc(hpos + d/2, -vpos, hpos, -vpos, hpos, -vpos, d/2, d/2); 227 hgoto(xc + d); /* circle goes to right side */ 228 vgoto(yc); 229 230 return (0); 231 } 232 233 int 234 dist(x1, y1, x2, y2) /* integer distance from x1,y1 to x2,y2 */ 235 { 236 float dx, dy; 237 238 dx = x2 - x1; 239 dy = y2 - y1; 240 return sqrt(dx*dx + dy*dy) + 0.5; 241 } 242 243 int 244 drawarc(dx1, dy1, dx2, dy2) 245 { 246 int x0, y0, x2, y2, r; 247 248 x0 = hpos + dx1; /* center */ 249 y0 = vpos + dy1; 250 x2 = x0 + dx2; /* "to" */ 251 y2 = y0 + dy2; 252 r = sqrt((float) dx1 * dx1 + (float) dy1 * dy1) + 0.5; 253 conicarc(x0, -y0, hpos, -vpos, x2, -y2, r, r); 254 255 return (0); 256 } 257 258 int 259 drawellip(a, b) 260 { 261 int xc, yc; 262 263 xc = hpos; 264 yc = vpos; 265 conicarc(hpos + a/2, -vpos, hpos, -vpos, hpos, -vpos, a/2, b/2); 266 hgoto(xc + a); 267 vgoto(yc); 268 269 return (0); 270 } 271 272 #define sqr(x) (long int)(x)*(x) 273 274 int 275 conicarc(x, y, x0, y0, x1, y1, a, b) 276 { 277 /* based on Bresenham, CACM, Feb 77, pp 102-3 */ 278 /* by Chris Van Wyk */ 279 /* capitalized vars are an internal reference frame */ 280 long dotcount = 0; 281 int osize, ofont; 282 int xs, ys, xt, yt, Xs, Ys, qs, Xt, Yt, qt, 283 M1x, M1y, M2x, M2y, M3x, M3y, 284 Q, move, Xc, Yc; 285 int ox1, oy1; 286 long delta; 287 float xc, yc; 288 float radius, slope; 289 float xstep, ystep; 290 291 osize = size; 292 setsize(t_size(pstab[osize-1] / drawsize)); 293 ox1 = x1; 294 oy1 = y1; 295 if (a != b) /* an arc of an ellipse; internally, will still think of circle */ 296 if (a > b) { 297 xstep = (float)a / b; 298 ystep = 1; 299 radius = b; 300 } else { 301 xstep = 1; 302 ystep = (float)b / a; 303 radius = a; 304 } 305 else { /* a circular arc; radius is computed from center and first point */ 306 xstep = ystep = 1; 307 radius = sqrt((float)(sqr(x0 - x) + sqr(y0 - y))); 308 } 309 310 311 xc = x0; 312 yc = y0; 313 /* now, use start and end point locations to figure out 314 the angle at which start and end happen; use these 315 angles with known radius to figure out where start 316 and end should be 317 */ 318 slope = atan2((double)(y0 - y), (double)(x0 - x) ); 319 if (slope == 0.0 && x0 < x) 320 slope = 3.14159265; 321 x0 = x + radius * cos(slope) + 0.5; 322 y0 = y + radius * sin(slope) + 0.5; 323 slope = atan2((double)(y1 - y), (double)(x1 - x)); 324 if (slope == 0.0 && x1 < x) 325 slope = 3.14159265; 326 x1 = x + radius * cos(slope) + 0.5; 327 y1 = y + radius * sin(slope) + 0.5; 328 /* step 2: translate to zero-centered circle */ 329 xs = x0 - x; 330 ys = y0 - y; 331 xt = x1 - x; 332 yt = y1 - y; 333 /* step 3: normalize to first quadrant */ 334 if (xs < 0) 335 if (ys < 0) { 336 Xs = abs(ys); 337 Ys = abs(xs); 338 qs = 3; 339 M1x = 0; 340 M1y = -1; 341 M2x = 1; 342 M2y = -1; 343 M3x = 1; 344 M3y = 0; 345 } else { 346 Xs = abs(xs); 347 Ys = abs(ys); 348 qs = 2; 349 M1x = -1; 350 M1y = 0; 351 M2x = -1; 352 M2y = -1; 353 M3x = 0; 354 M3y = -1; 355 } 356 else if (ys < 0) { 357 Xs = abs(xs); 358 Ys = abs(ys); 359 qs = 0; 360 M1x = 1; 361 M1y = 0; 362 M2x = 1; 363 M2y = 1; 364 M3x = 0; 365 M3y = 1; 366 } else { 367 Xs = abs(ys); 368 Ys = abs(xs); 369 qs = 1; 370 M1x = 0; 371 M1y = 1; 372 M2x = -1; 373 M2y = 1; 374 M3x = -1; 375 M3y = 0; 376 } 377 378 379 Xc = Xs; 380 Yc = Ys; 381 if (xt < 0) 382 if (yt < 0) { 383 Xt = abs(yt); 384 Yt = abs(xt); 385 qt = 3; 386 } else { 387 Xt = abs(xt); 388 Yt = abs(yt); 389 qt = 2; 390 } 391 else if (yt < 0) { 392 Xt = abs(xt); 393 Yt = abs(yt); 394 qt = 0; 395 } else { 396 Xt = abs(yt); 397 Yt = abs(xt); 398 qt = 1; 399 } 400 401 402 /* step 4: calculate number of quadrant crossings */ 403 if (((4 + qt - qs) 404 % 4 == 0) 405 && (Xt <= Xs) 406 && (Yt >= Ys) 407 ) 408 Q = 3; 409 else 410 Q = (4 + qt - qs) % 4 - 1; 411 /* step 5: calculate initial decision difference */ 412 delta = sqr(Xs + 1) 413 + sqr(Ys - 1) 414 -sqr(xs) 415 -sqr(ys); 416 /* here begins the work of drawing 417 we hope it ends here too */ 418 while ((Q >= 0) 419 || ((Q > -2) 420 && ((Xt > Xc) 421 && (Yt < Yc) 422 ) 423 ) 424 ) { 425 if (dotcount++ % DX == 0) 426 putdot((int)xc, (int)yc); 427 if (Yc < 0.5) { 428 /* reinitialize */ 429 Xs = Xc = 0; 430 Ys = Yc = sqrt((float)(sqr(xs) + sqr(ys))); 431 delta = sqr(Xs + 1) + sqr(Ys - 1) - sqr(xs) - sqr(ys); 432 Q--; 433 M1x = M3x; 434 M1y = M3y; 435 { 436 int T; 437 T = M2y; 438 M2y = M2x; 439 M2x = -T; 440 T = M3y; 441 M3y = M3x; 442 M3x = -T; 443 } 444 } else { 445 if (delta <= 0) 446 if (2 * delta + 2 * Yc - 1 <= 0) 447 move = 1; 448 else 449 move = 2; 450 else if (2 * delta - 2 * Xc - 1 <= 0) 451 move = 2; 452 else 453 move = 3; 454 switch (move) { 455 case 1: 456 Xc++; 457 delta += 2 * Xc + 1; 458 xc += M1x * xstep; 459 yc += M1y * ystep; 460 break; 461 case 2: 462 Xc++; 463 Yc--; 464 delta += 2 * Xc - 2 * Yc + 2; 465 xc += M2x * xstep; 466 yc += M2y * ystep; 467 break; 468 case 3: 469 Yc--; 470 delta -= 2 * Yc + 1; 471 xc += M3x * xstep; 472 yc += M3y * ystep; 473 break; 474 } 475 } 476 } 477 478 479 setsize(osize); 480 drawline((int)xc-ox1,(int)yc-oy1,"."); 481 482 return (0); 483 } 484 485 int 486 putdot(x, y) 487 { 488 arcmove(x, y); 489 put1(drawdot); 490 491 return (0); 492 } 493