xref: /freebsd/lib/libvgl/simple.c (revision 731d06abf2105cc0873fa84e972178f9f37ca760)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1991-1997 Søren Schmidt
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer
12  *    in this position and unchanged.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. The name of the author may not be used to endorse or promote products
17  *    derived from this software without specific prior written permission
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <signal.h>
35 #include <sys/fbio.h>
36 #include <sys/endian.h>
37 #include "vgl.h"
38 
39 static byte VGLSavePaletteRed[256];
40 static byte VGLSavePaletteGreen[256];
41 static byte VGLSavePaletteBlue[256];
42 
43 #define ABS(a)		(((a)<0) ? -(a) : (a))
44 #define SGN(a)		(((a)<0) ? -1 : 1)
45 #define min(x, y)	(((x) < (y)) ? (x) : (y))
46 #define max(x, y)	(((x) > (y)) ? (x) : (y))
47 
48 void
49 VGLSetXY(VGLBitmap *object, int x, int y, u_long color)
50 {
51   int offset;
52 
53   VGLCheckSwitch();
54   if (x>=0 && x<object->VXsize && y>=0 && y<object->VYsize) {
55     if (object->Type == MEMBUF ||
56         !VGLMouseFreeze(x, y, 1, 1, 0x80000000 | color)) {
57       offset = (y * object->VXsize + x) * object->PixelBytes;
58       switch (object->Type) {
59       case VIDBUF8S:
60       case VIDBUF16S:
61       case VIDBUF24S:
62       case VIDBUF32S:
63         offset = VGLSetSegment(offset);
64         /* FALLTHROUGH */
65       case MEMBUF:
66       case VIDBUF8:
67       case VIDBUF16:
68       case VIDBUF24:
69       case VIDBUF32:
70         color = htole32(color);
71         switch (object->PixelBytes) {
72         case 1:
73           memcpy(&object->Bitmap[offset], &color, 1);
74           break;
75         case 2:
76           memcpy(&object->Bitmap[offset], &color, 2);
77           break;
78         case 3:
79           memcpy(&object->Bitmap[offset], &color, 3);
80           break;
81         case 4:
82           memcpy(&object->Bitmap[offset], &color, 4);
83           break;
84         }
85         break;
86       case VIDBUF8X:
87         outb(0x3c4, 0x02);
88         outb(0x3c5, 0x01 << (x&0x3));
89 	object->Bitmap[(unsigned)(VGLAdpInfo.va_line_width*y)+(x/4)] = ((byte)color);
90 	break;
91       case VIDBUF4S:
92 	offset = VGLSetSegment(y*VGLAdpInfo.va_line_width + x/8);
93 	goto set_planar;
94       case VIDBUF4:
95 	offset = y*VGLAdpInfo.va_line_width + x/8;
96 set_planar:
97         outb(0x3c4, 0x02); outb(0x3c5, 0x0f);
98         outb(0x3ce, 0x00); outb(0x3cf, (byte)color & 0x0f);	/* set/reset */
99         outb(0x3ce, 0x01); outb(0x3cf, 0x0f);		/* set/reset enable */
100         outb(0x3ce, 0x08); outb(0x3cf, 0x80 >> (x%8));	/* bit mask */
101 	object->Bitmap[offset] |= (byte)color;
102       }
103     }
104     if (object->Type != MEMBUF)
105       VGLMouseUnFreeze();
106   }
107 }
108 
109 static u_long
110 __VGLGetXY(VGLBitmap *object, int x, int y)
111 {
112   int offset;
113   int i;
114   u_long color;
115   byte mask;
116 
117   offset = (y * object->VXsize + x) * object->PixelBytes;
118   switch (object->Type) {
119     case VIDBUF8S:
120     case VIDBUF16S:
121     case VIDBUF24S:
122     case VIDBUF32S:
123       offset = VGLSetSegment(offset);
124       /* FALLTHROUGH */
125     case MEMBUF:
126     case VIDBUF8:
127     case VIDBUF16:
128     case VIDBUF24:
129     case VIDBUF32:
130       switch (object->PixelBytes) {
131       case 1:
132         memcpy(&color, &object->Bitmap[offset], 1);
133         return le32toh(color) & 0xff;
134       case 2:
135         memcpy(&color, &object->Bitmap[offset], 2);
136         return le32toh(color) & 0xffff;
137       case 3:
138         memcpy(&color, &object->Bitmap[offset], 3);
139         return le32toh(color) & 0xffffff;
140       case 4:
141         memcpy(&color, &object->Bitmap[offset], 4);
142         return le32toh(color);
143       }
144       break;
145     case VIDBUF8X:
146       outb(0x3ce, 0x04); outb(0x3cf, x & 0x3);
147       return object->Bitmap[(unsigned)(VGLAdpInfo.va_line_width*y)+(x/4)];
148     case VIDBUF4S:
149       offset = VGLSetSegment(y*VGLAdpInfo.va_line_width + x/8);
150       goto get_planar;
151     case VIDBUF4:
152       offset = y*VGLAdpInfo.va_line_width + x/8;
153 get_planar:
154       color = 0;
155       mask = 0x80 >> (x%8);
156       for (i = 0; i < VGLModeInfo.vi_planes; i++) {
157 	outb(0x3ce, 0x04); outb(0x3cf, i);
158 	color |= (((volatile VGLBitmap *)object)->Bitmap[offset] & mask) ?
159 		 (1 << i) : 0;
160       }
161       return color;
162   }
163   return 0;		/* XXX black? */
164 }
165 
166 u_long
167 VGLGetXY(VGLBitmap *object, int x, int y)
168 {
169   u_long color;
170 
171   VGLCheckSwitch();
172   if (x<0 || x>=object->VXsize || y<0 || y>=object->VYsize)
173     return 0;
174   if (object->Type != MEMBUF) {
175     color = VGLMouseFreeze(x, y, 1, 1, 0x40000000);
176     if (color & 0x40000000) {
177       VGLMouseUnFreeze();
178       return color & 0xffffff;
179     }
180   }
181   color = __VGLGetXY(object, x, y);
182   if (object->Type != MEMBUF)
183     VGLMouseUnFreeze();
184   return color;
185 }
186 
187  /*
188   * Symmetric Double Step Line Algorithm by Brian Wyvill from
189   * "Graphics Gems", Academic Press, 1990.
190   */
191 
192 #define SL_SWAP(a,b)           {a^=b; b^=a; a^=b;}
193 #define SL_ABSOLUTE(i,j,k)     ( (i-j)*(k = ( (i-j)<0 ? -1 : 1)))
194 
195 void
196 plot(VGLBitmap * object, int x, int y, int flag, u_long color)
197 {
198   /* non-zero flag indicates the pixels need swapping back. */
199   if (flag)
200     VGLSetXY(object, y, x, color);
201   else
202     VGLSetXY(object, x, y, color);
203 }
204 
205 
206 void
207 VGLLine(VGLBitmap *object, int x1, int y1, int x2, int y2, u_long color)
208 {
209   int dx, dy, incr1, incr2, D, x, y, xend, c, pixels_left;
210   int sign_x, sign_y, step, reverse, i;
211 
212   dx = SL_ABSOLUTE(x2, x1, sign_x);
213   dy = SL_ABSOLUTE(y2, y1, sign_y);
214   /* decide increment sign by the slope sign */
215   if (sign_x == sign_y)
216     step = 1;
217   else
218     step = -1;
219 
220   if (dy > dx) {	/* chooses axis of greatest movement (make dx) */
221     SL_SWAP(x1, y1);
222     SL_SWAP(x2, y2);
223     SL_SWAP(dx, dy);
224     reverse = 1;
225   } else
226     reverse = 0;
227   /* note error check for dx==0 should be included here */
228   if (x1 > x2) {      /* start from the smaller coordinate */
229     x = x2;
230     y = y2;
231 /*  x1 = x1;
232     y1 = y1; */
233   } else {
234     x = x1;
235     y = y1;
236     x1 = x2;
237     y1 = y2;
238   }
239 
240 
241   /* Note dx=n implies 0 - n or (dx+1) pixels to be set */
242   /* Go round loop dx/4 times then plot last 0,1,2 or 3 pixels */
243   /* In fact (dx-1)/4 as 2 pixels are already plotted */
244   xend = (dx - 1) / 4;
245   pixels_left = (dx - 1) % 4;  /* number of pixels left over at the
246            * end */
247   plot(object, x, y, reverse, color);
248   if (pixels_left < 0)
249     return;      /* plot only one pixel for zero length
250            * vectors */
251   plot(object, x1, y1, reverse, color);  /* plot first two points */
252   incr2 = 4 * dy - 2 * dx;
253   if (incr2 < 0) {    /* slope less than 1/2 */
254     c = 2 * dy;
255     incr1 = 2 * c;
256     D = incr1 - dx;
257 
258     for (i = 0; i < xend; i++) {  /* plotting loop */
259       ++x;
260       --x1;
261       if (D < 0) {
262         /* pattern 1 forwards */
263         plot(object, x, y, reverse, color);
264         plot(object, ++x, y, reverse, color);
265         /* pattern 1 backwards */
266         plot(object, x1, y1, reverse, color);
267         plot(object, --x1, y1, reverse, color);
268         D += incr1;
269       } else {
270         if (D < c) {
271           /* pattern 2 forwards */
272           plot(object, x, y, reverse, color);
273           plot(object, ++x, y += step, reverse,
274               color);
275           /* pattern 2 backwards */
276           plot(object, x1, y1, reverse, color);
277           plot(object, --x1, y1 -= step, reverse,
278               color);
279         } else {
280           /* pattern 3 forwards */
281           plot(object, x, y += step, reverse, color);
282           plot(object, ++x, y, reverse, color);
283           /* pattern 3 backwards */
284           plot(object, x1, y1 -= step, reverse,
285               color);
286           plot(object, --x1, y1, reverse, color);
287         }
288         D += incr2;
289       }
290     }      /* end for */
291 
292     /* plot last pattern */
293     if (pixels_left) {
294       if (D < 0) {
295         plot(object, ++x, y, reverse, color);  /* pattern 1 */
296         if (pixels_left > 1)
297           plot(object, ++x, y, reverse, color);
298         if (pixels_left > 2)
299           plot(object, --x1, y1, reverse, color);
300       } else {
301         if (D < c) {
302           plot(object, ++x, y, reverse, color);  /* pattern 2  */
303           if (pixels_left > 1)
304             plot(object, ++x, y += step, reverse, color);
305           if (pixels_left > 2)
306             plot(object, --x1, y1, reverse, color);
307         } else {
308           /* pattern 3 */
309           plot(object, ++x, y += step, reverse, color);
310           if (pixels_left > 1)
311             plot(object, ++x, y, reverse, color);
312           if (pixels_left > 2)
313             plot(object, --x1, y1 -= step, reverse, color);
314         }
315       }
316     }      /* end if pixels_left */
317   }
318   /* end slope < 1/2 */
319   else {        /* slope greater than 1/2 */
320     c = 2 * (dy - dx);
321     incr1 = 2 * c;
322     D = incr1 + dx;
323     for (i = 0; i < xend; i++) {
324       ++x;
325       --x1;
326       if (D > 0) {
327         /* pattern 4 forwards */
328         plot(object, x, y += step, reverse, color);
329         plot(object, ++x, y += step, reverse, color);
330         /* pattern 4 backwards */
331         plot(object, x1, y1 -= step, reverse, color);
332         plot(object, --x1, y1 -= step, reverse, color);
333         D += incr1;
334       } else {
335         if (D < c) {
336           /* pattern 2 forwards */
337           plot(object, x, y, reverse, color);
338           plot(object, ++x, y += step, reverse,
339               color);
340 
341           /* pattern 2 backwards */
342           plot(object, x1, y1, reverse, color);
343           plot(object, --x1, y1 -= step, reverse,
344               color);
345         } else {
346           /* pattern 3 forwards */
347           plot(object, x, y += step, reverse, color);
348           plot(object, ++x, y, reverse, color);
349           /* pattern 3 backwards */
350           plot(object, x1, y1 -= step, reverse, color);
351           plot(object, --x1, y1, reverse, color);
352         }
353         D += incr2;
354       }
355     }      /* end for */
356     /* plot last pattern */
357     if (pixels_left) {
358       if (D > 0) {
359         plot(object, ++x, y += step, reverse, color);  /* pattern 4 */
360         if (pixels_left > 1)
361           plot(object, ++x, y += step, reverse,
362               color);
363         if (pixels_left > 2)
364           plot(object, --x1, y1 -= step, reverse,
365               color);
366       } else {
367         if (D < c) {
368           plot(object, ++x, y, reverse, color);  /* pattern 2  */
369           if (pixels_left > 1)
370             plot(object, ++x, y += step, reverse, color);
371           if (pixels_left > 2)
372             plot(object, --x1, y1, reverse, color);
373         } else {
374           /* pattern 3 */
375           plot(object, ++x, y += step, reverse, color);
376           if (pixels_left > 1)
377             plot(object, ++x, y, reverse, color);
378           if (pixels_left > 2) {
379             if (D > c)  /* step 3 */
380               plot(object, --x1, y1 -= step, reverse, color);
381             else  /* step 2 */
382               plot(object, --x1, y1, reverse, color);
383           }
384         }
385       }
386     }
387   }
388 }
389 
390 void
391 VGLBox(VGLBitmap *object, int x1, int y1, int x2, int y2, u_long color)
392 {
393   VGLLine(object, x1, y1, x2, y1, color);
394   VGLLine(object, x2, y1, x2, y2, color);
395   VGLLine(object, x2, y2, x1, y2, color);
396   VGLLine(object, x1, y2, x1, y1, color);
397 }
398 
399 void
400 VGLFilledBox(VGLBitmap *object, int x1, int y1, int x2, int y2, u_long color)
401 {
402   int y;
403 
404   for (y=y1; y<=y2; y++) VGLLine(object, x1, y, x2, y, color);
405 }
406 
407 static inline void
408 set4pixels(VGLBitmap *object, int x, int y, int xc, int yc, u_long color)
409 {
410   if (x!=0) {
411     VGLSetXY(object, xc+x, yc+y, color);
412     VGLSetXY(object, xc-x, yc+y, color);
413     if (y!=0) {
414       VGLSetXY(object, xc+x, yc-y, color);
415       VGLSetXY(object, xc-x, yc-y, color);
416     }
417   }
418   else {
419     VGLSetXY(object, xc, yc+y, color);
420     if (y!=0)
421       VGLSetXY(object, xc, yc-y, color);
422   }
423 }
424 
425 void
426 VGLEllipse(VGLBitmap *object, int xc, int yc, int a, int b, u_long color)
427 {
428   int x = 0, y = b, asq = a*a, asq2 = a*a*2, bsq = b*b;
429   int bsq2 = b*b*2, d = bsq-asq*b+asq/4, dx = 0, dy = asq2*b;
430 
431   while (dx<dy) {
432     set4pixels(object, x, y, xc, yc, color);
433     if (d>0) {
434       y--; dy-=asq2; d-=dy;
435     }
436     x++; dx+=bsq2; d+=bsq+dx;
437   }
438   d+=(3*(asq-bsq)/2-(dx+dy))/2;
439   while (y>=0) {
440     set4pixels(object, x, y, xc, yc, color);
441     if (d<0) {
442       x++; dx+=bsq2; d+=dx;
443     }
444     y--; dy-=asq2; d+=asq-dy;
445   }
446 }
447 
448 static inline void
449 set2lines(VGLBitmap *object, int x, int y, int xc, int yc, u_long color)
450 {
451   if (x!=0) {
452     VGLLine(object, xc+x, yc+y, xc-x, yc+y, color);
453     if (y!=0)
454       VGLLine(object, xc+x, yc-y, xc-x, yc-y, color);
455   }
456   else {
457     VGLLine(object, xc, yc+y, xc, yc-y, color);
458   }
459 }
460 
461 void
462 VGLFilledEllipse(VGLBitmap *object, int xc, int yc, int a, int b, u_long color)
463 {
464   int x = 0, y = b, asq = a*a, asq2 = a*a*2, bsq = b*b;
465   int bsq2 = b*b*2, d = bsq-asq*b+asq/4, dx = 0, dy = asq2*b;
466 
467   while (dx<dy) {
468     set2lines(object, x, y, xc, yc, color);
469     if (d>0) {
470       y--; dy-=asq2; d-=dy;
471     }
472     x++; dx+=bsq2; d+=bsq+dx;
473   }
474   d+=(3*(asq-bsq)/2-(dx+dy))/2;
475   while (y>=0) {
476     set2lines(object, x, y, xc, yc, color);
477     if (d<0) {
478       x++; dx+=bsq2; d+=dx;
479     }
480     y--; dy-=asq2; d+=asq-dy;
481   }
482 }
483 
484 void
485 VGLClear(VGLBitmap *object, u_long color)
486 {
487   VGLBitmap src;
488   int offset;
489   int len;
490   int i;
491 
492   VGLCheckSwitch();
493   if (object->Type != MEMBUF)
494     VGLMouseFreeze(0, 0, object->Xsize, object->Ysize, color);
495   switch (object->Type) {
496   case MEMBUF:
497   case VIDBUF8:
498   case VIDBUF8S:
499   case VIDBUF16:
500   case VIDBUF16S:
501   case VIDBUF24:
502   case VIDBUF24S:
503   case VIDBUF32:
504   case VIDBUF32S:
505     src.Type = MEMBUF;
506     src.Xsize = object->Xsize;
507     src.VXsize = object->VXsize;
508     src.Ysize = 1;
509     src.VYsize = 1;
510     src.Xorigin = 0;
511     src.Yorigin = 0;
512     src.Bitmap = alloca(object->VXsize * object->PixelBytes);
513     src.PixelBytes = object->PixelBytes;
514     color = htole32(color);
515     for (i = 0; i < object->VXsize; i++)
516       bcopy(&color, src.Bitmap + i * object->PixelBytes, object->PixelBytes);
517     for (i = 0; i < object->VYsize; i++)
518       __VGLBitmapCopy(&src, 0, 0, object, 0, i, object->VXsize, 1);
519     break;
520 
521   case VIDBUF8X:
522     /* XXX works only for Xsize % 4 = 0 */
523     outb(0x3c6, 0xff);
524     outb(0x3c4, 0x02); outb(0x3c5, 0x0f);
525     memset(object->Bitmap, (byte)color, VGLAdpInfo.va_line_width*object->VYsize);
526     break;
527 
528   case VIDBUF4:
529   case VIDBUF4S:
530     /* XXX works only for Xsize % 8 = 0 */
531     outb(0x3c4, 0x02); outb(0x3c5, 0x0f);
532     outb(0x3ce, 0x05); outb(0x3cf, 0x02);		/* mode 2 */
533     outb(0x3ce, 0x01); outb(0x3cf, 0x00);		/* set/reset enable */
534     outb(0x3ce, 0x08); outb(0x3cf, 0xff);		/* bit mask */
535     for (offset = 0; offset < VGLAdpInfo.va_line_width*object->VYsize; ) {
536       VGLSetSegment(offset);
537       len = min(object->VXsize*object->VYsize - offset,
538 		VGLAdpInfo.va_window_size);
539       memset(object->Bitmap, (byte)color, len);
540       offset += len;
541     }
542     outb(0x3ce, 0x05); outb(0x3cf, 0x00);
543     break;
544   }
545   if (object->Type != MEMBUF)
546     VGLMouseUnFreeze();
547 }
548 
549 void
550 VGLRestorePalette()
551 {
552   int i;
553 
554   outb(0x3C6, 0xFF);
555   inb(0x3DA);
556   outb(0x3C8, 0x00);
557   for (i=0; i<256; i++) {
558     outb(0x3C9, VGLSavePaletteRed[i]);
559     inb(0x84);
560     outb(0x3C9, VGLSavePaletteGreen[i]);
561     inb(0x84);
562     outb(0x3C9, VGLSavePaletteBlue[i]);
563     inb(0x84);
564   }
565   inb(0x3DA);
566   outb(0x3C0, 0x20);
567 }
568 
569 void
570 VGLSavePalette()
571 {
572   int i;
573 
574   outb(0x3C6, 0xFF);
575   inb(0x3DA);
576   outb(0x3C7, 0x00);
577   for (i=0; i<256; i++) {
578     VGLSavePaletteRed[i] = inb(0x3C9);
579     inb(0x84);
580     VGLSavePaletteGreen[i] = inb(0x3C9);
581     inb(0x84);
582     VGLSavePaletteBlue[i] = inb(0x3C9);
583     inb(0x84);
584   }
585   inb(0x3DA);
586   outb(0x3C0, 0x20);
587 }
588 
589 void
590 VGLSetPalette(byte *red, byte *green, byte *blue)
591 {
592   int i;
593 
594   for (i=0; i<256; i++) {
595     VGLSavePaletteRed[i] = red[i];
596     VGLSavePaletteGreen[i] = green[i];
597     VGLSavePaletteBlue[i] = blue[i];
598   }
599   VGLCheckSwitch();
600   outb(0x3C6, 0xFF);
601   inb(0x3DA);
602   outb(0x3C8, 0x00);
603   for (i=0; i<256; i++) {
604     outb(0x3C9, VGLSavePaletteRed[i]);
605     inb(0x84);
606     outb(0x3C9, VGLSavePaletteGreen[i]);
607     inb(0x84);
608     outb(0x3C9, VGLSavePaletteBlue[i]);
609     inb(0x84);
610   }
611   inb(0x3DA);
612   outb(0x3C0, 0x20);
613 }
614 
615 void
616 VGLSetPaletteIndex(byte color, byte red, byte green, byte blue)
617 {
618   VGLSavePaletteRed[color] = red;
619   VGLSavePaletteGreen[color] = green;
620   VGLSavePaletteBlue[color] = blue;
621   VGLCheckSwitch();
622   outb(0x3C6, 0xFF);
623   inb(0x3DA);
624   outb(0x3C8, color);
625   outb(0x3C9, red); outb(0x3C9, green); outb(0x3C9, blue);
626   inb(0x3DA);
627   outb(0x3C0, 0x20);
628 }
629 
630 void
631 VGLSetBorder(byte color)
632 {
633   VGLCheckSwitch();
634   inb(0x3DA);
635   outb(0x3C0,0x11); outb(0x3C0, color);
636   inb(0x3DA);
637   outb(0x3C0, 0x20);
638 }
639 
640 void
641 VGLBlankDisplay(int blank)
642 {
643   byte val;
644 
645   VGLCheckSwitch();
646   outb(0x3C4, 0x01); val = inb(0x3C5); outb(0x3C4, 0x01);
647   outb(0x3C5, ((blank) ? (val |= 0x20) : (val &= 0xDF)));
648 }
649