s_copypix.c revision 38a1c2b4959d35236933c14d3944cce94283ca30 
1/*
2 * Mesa 3-D graphics library
3 * Version:  6.5.2
4 *
5 * Copyright (C) 1999-2006  Brian Paul   All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25
26#include "glheader.h"
27#include "context.h"
28#include "colormac.h"
29#include "convolve.h"
30#include "histogram.h"
31#include "image.h"
32#include "macros.h"
33#include "imports.h"
34#include "pixel.h"
35
36#include "s_context.h"
37#include "s_depth.h"
38#include "s_span.h"
39#include "s_stencil.h"
40#include "s_zoom.h"
41
42
43
44/**
45 * Determine if there's overlap in an image copy.
46 * This test also compensates for the fact that copies are done from
47 * bottom to top and overlaps can sometimes be handled correctly
48 * without making a temporary image copy.
49 * \return GL_TRUE if the regions overlap, GL_FALSE otherwise.
50 */
51static GLboolean
52regions_overlap(GLint srcx, GLint srcy,
53                GLint dstx, GLint dsty,
54                GLint width, GLint height,
55                GLfloat zoomX, GLfloat zoomY)
56{
57   if (zoomX == 1.0 && zoomY == 1.0) {
58      /* no zoom */
59      if (srcx >= dstx + width || (srcx + width <= dstx)) {
60         return GL_FALSE;
61      }
62      else if (srcy < dsty) { /* this is OK */
63         return GL_FALSE;
64      }
65      else if (srcy > dsty + height) {
66         return GL_FALSE;
67      }
68      else {
69         return GL_TRUE;
70      }
71   }
72   else {
73      /* add one pixel of slop when zooming, just to be safe */
74      if ((srcx > dstx + (width * zoomX) + 1) || (srcx + width + 1 < dstx)) {
75         return GL_FALSE;
76      }
77      else if ((srcy < dsty) && (srcy + height < dsty + (height * zoomY))) {
78         return GL_FALSE;
79      }
80      else if ((srcy > dsty) && (srcy + height > dsty + (height * zoomY))) {
81         return GL_FALSE;
82      }
83      else {
84         return GL_TRUE;
85      }
86   }
87}
88
89
90/**
91 * RGBA copypixels with convolution.
92 */
93static void
94copy_conv_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
95                      GLint width, GLint height, GLint destx, GLint desty)
96{
97   SWcontext *swrast = SWRAST_CONTEXT(ctx);
98   GLint row;
99   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
100   const GLbitfield transferOps = ctx->_ImageTransferState;
101   const GLboolean sink = (ctx->Pixel.MinMaxEnabled && ctx->MinMax.Sink)
102      || (ctx->Pixel.HistogramEnabled && ctx->Histogram.Sink);
103   GLfloat *dest, *tmpImage, *convImage;
104   SWspan span;
105
106   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_RGBA);
107
108   if (ctx->Depth.Test)
109      _swrast_span_default_z(ctx, &span);
110   if (swrast->_FogEnabled)
111      _swrast_span_default_fog(ctx, &span);
112   if (ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)
113      _swrast_span_default_secondary_color(ctx, &span);
114
115   /* allocate space for GLfloat image */
116   tmpImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
117   if (!tmpImage) {
118      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
119      return;
120   }
121   convImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
122   if (!convImage) {
123      _mesa_free(tmpImage);
124      _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
125      return;
126   }
127
128   /* read source image as float/RGBA */
129   dest = tmpImage;
130   for (row = 0; row < height; row++) {
131      _swrast_read_rgba_span(ctx, ctx->ReadBuffer->_ColorReadBuffer,
132                             width, srcx, srcy + row, GL_FLOAT, dest);
133      dest += 4 * width;
134   }
135
136   /* do the image transfer ops which preceed convolution */
137   for (row = 0; row < height; row++) {
138      GLfloat (*rgba)[4] = (GLfloat (*)[4]) (tmpImage + row * width * 4);
139      _mesa_apply_rgba_transfer_ops(ctx,
140                                    transferOps & IMAGE_PRE_CONVOLUTION_BITS,
141                                    width, rgba);
142   }
143
144   /* do convolution */
145   if (ctx->Pixel.Convolution2DEnabled) {
146      _mesa_convolve_2d_image(ctx, &width, &height, tmpImage, convImage);
147   }
148   else {
149      ASSERT(ctx->Pixel.Separable2DEnabled);
150      _mesa_convolve_sep_image(ctx, &width, &height, tmpImage, convImage);
151   }
152   _mesa_free(tmpImage);
153
154   /* do remaining post-convolution image transfer ops */
155   for (row = 0; row < height; row++) {
156      GLfloat (*rgba)[4] = (GLfloat (*)[4]) (convImage + row * width * 4);
157      _mesa_apply_rgba_transfer_ops(ctx,
158                                    transferOps & IMAGE_POST_CONVOLUTION_BITS,
159                                    width, rgba);
160   }
161
162   if (!sink) {
163      /* write the new image */
164      for (row = 0; row < height; row++) {
165         const GLfloat *src = convImage + row * width * 4;
166         GLvoid *rgba = span.array->color.sz1.rgba; /* row storage */
167
168         /* copy convolved colors into span array */
169         _mesa_memcpy(rgba, src, width * 4 * sizeof(GLfloat));
170
171         /* write span */
172         span.x = destx;
173         span.y = desty + row;
174         span.end = width;
175         span.array->ChanType = GL_FLOAT;
176         if (zoom) {
177            _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
178         }
179         else {
180            _swrast_write_rgba_span(ctx, &span);
181         }
182      }
183      /* restore this */
184      span.array->ChanType = CHAN_TYPE;
185   }
186
187   _mesa_free(convImage);
188}
189
190
191/**
192 * RGBA copypixels
193 */
194static void
195copy_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
196                 GLint width, GLint height, GLint destx, GLint desty)
197{
198   SWcontext *swrast = SWRAST_CONTEXT(ctx);
199   GLfloat *tmpImage, *p;
200   GLint sy, dy, stepy, row;
201   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
202   GLint overlapping;
203   GLuint transferOps = ctx->_ImageTransferState;
204   SWspan span;
205
206   if (!ctx->ReadBuffer->_ColorReadBuffer) {
207      /* no readbuffer - OK */
208      return;
209   }
210
211   if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) {
212      copy_conv_rgba_pixels(ctx, srcx, srcy, width, height, destx, desty);
213      return;
214   }
215   else if (ctx->Pixel.Convolution1DEnabled) {
216      /* make sure we don't apply 1D convolution */
217      transferOps &= ~(IMAGE_CONVOLUTION_BIT |
218                       IMAGE_POST_CONVOLUTION_SCALE_BIAS);
219   }
220
221   /* Determine if copy should be done bottom-to-top or top-to-bottom */
222   if (srcy < desty) {
223      /* top-down  max-to-min */
224      sy = srcy + height - 1;
225      dy = desty + height - 1;
226      stepy = -1;
227   }
228   else {
229      /* bottom-up  min-to-max */
230      sy = srcy;
231      dy = desty;
232      stepy = 1;
233   }
234
235   if (ctx->DrawBuffer == ctx->ReadBuffer) {
236      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
237                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
238   }
239   else {
240      overlapping = GL_FALSE;
241   }
242
243   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_RGBA);
244   if (ctx->Depth.Test)
245      _swrast_span_default_z(ctx, &span);
246   if (swrast->_FogEnabled)
247      _swrast_span_default_fog(ctx, &span);
248   if (ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)
249      _swrast_span_default_secondary_color(ctx, &span);
250
251   if (overlapping) {
252      tmpImage = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat) * 4);
253      if (!tmpImage) {
254         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
255         return;
256      }
257      /* read the source image as RGBA/float */
258      p = tmpImage;
259      for (row = 0; row < height; row++) {
260         _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
261                                 width, srcx, sy + row, GL_FLOAT, p );
262         p += width * 4;
263      }
264      p = tmpImage;
265   }
266   else {
267      tmpImage = NULL;  /* silence compiler warnings */
268      p = NULL;
269   }
270
271   ASSERT(width < MAX_WIDTH);
272
273   for (row = 0; row < height; row++, sy += stepy, dy += stepy) {
274      GLvoid *rgba = span.array->attribs[FRAG_ATTRIB_COL0];
275
276      /* Get row/span of source pixels */
277      if (overlapping) {
278         /* get from buffered image */
279         _mesa_memcpy(rgba, p, width * sizeof(GLfloat) * 4);
280         p += width * 4;
281      }
282      else {
283         /* get from framebuffer */
284         _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
285                                 width, srcx, sy, GL_FLOAT, rgba );
286      }
287
288      if (transferOps) {
289         _mesa_apply_rgba_transfer_ops(ctx, transferOps, width,
290                                       (GLfloat (*)[4]) rgba);
291      }
292
293      /* Write color span */
294      span.x = destx;
295      span.y = dy;
296      span.end = width;
297      span.array->ChanType = GL_FLOAT;
298      if (zoom) {
299         _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
300      }
301      else {
302         _swrast_write_rgba_span(ctx, &span);
303      }
304   }
305
306   span.array->ChanType = CHAN_TYPE; /* restore */
307
308   if (overlapping)
309      _mesa_free(tmpImage);
310}
311
312
313static void
314copy_ci_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
315                GLint width, GLint height,
316                GLint destx, GLint desty )
317{
318   SWcontext *swrast = SWRAST_CONTEXT(ctx);
319   GLuint *tmpImage,*p;
320   GLint sy, dy, stepy;
321   GLint j;
322   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
323   GLint overlapping;
324   SWspan span;
325
326   if (!ctx->ReadBuffer->_ColorReadBuffer) {
327      /* no readbuffer - OK */
328      return;
329   }
330
331   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_INDEX);
332
333   /* Determine if copy should be bottom-to-top or top-to-bottom */
334   if (srcy<desty) {
335      /* top-down  max-to-min */
336      sy = srcy + height - 1;
337      dy = desty + height - 1;
338      stepy = -1;
339   }
340   else {
341      /* bottom-up  min-to-max */
342      sy = srcy;
343      dy = desty;
344      stepy = 1;
345   }
346
347   if (ctx->DrawBuffer == ctx->ReadBuffer) {
348      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
349                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
350   }
351   else {
352      overlapping = GL_FALSE;
353   }
354
355   if (ctx->Depth.Test)
356      _swrast_span_default_z(ctx, &span);
357   if (swrast->_FogEnabled)
358      _swrast_span_default_fog(ctx, &span);
359
360   if (overlapping) {
361      GLint ssy = sy;
362      tmpImage = (GLuint *) _mesa_malloc(width * height * sizeof(GLuint));
363      if (!tmpImage) {
364         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
365         return;
366      }
367      /* read the image */
368      p = tmpImage;
369      for (j = 0; j < height; j++, ssy += stepy) {
370         _swrast_read_index_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
371                                  width, srcx, ssy, p );
372         p += width;
373      }
374      p = tmpImage;
375   }
376   else {
377      tmpImage = NULL;  /* silence compiler warning */
378      p = NULL;
379   }
380
381   for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
382      /* Get color indexes */
383      if (overlapping) {
384         _mesa_memcpy(span.array->index, p, width * sizeof(GLuint));
385         p += width;
386      }
387      else {
388         _swrast_read_index_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
389                                  width, srcx, sy, span.array->index );
390      }
391
392      if (ctx->_ImageTransferState)
393         _mesa_apply_ci_transfer_ops(ctx, ctx->_ImageTransferState,
394                                     width, span.array->index);
395
396      /* write color indexes */
397      span.x = destx;
398      span.y = dy;
399      span.end = width;
400      if (zoom)
401         _swrast_write_zoomed_index_span(ctx, destx, desty, &span);
402      else
403         _swrast_write_index_span(ctx, &span);
404   }
405
406   if (overlapping)
407      _mesa_free(tmpImage);
408}
409
410
411/**
412 * Convert floating point Z values to integer Z values with pixel transfer's
413 * Z scale and bias.
414 */
415static void
416scale_and_bias_z(GLcontext *ctx, GLuint width,
417                 const GLfloat depth[], GLuint z[])
418{
419   const GLuint depthMax = ctx->DrawBuffer->_DepthMax;
420   GLuint i;
421
422   if (depthMax <= 0xffffff &&
423       ctx->Pixel.DepthScale == 1.0 &&
424       ctx->Pixel.DepthBias == 0.0) {
425      /* no scale or bias and no clamping and no worry of overflow */
426      const GLfloat depthMaxF = ctx->DrawBuffer->_DepthMaxF;
427      for (i = 0; i < width; i++) {
428         z[i] = (GLuint) (depth[i] * depthMaxF);
429      }
430   }
431   else {
432      /* need to be careful with overflow */
433      const GLdouble depthMaxF = ctx->DrawBuffer->_DepthMaxF;
434      for (i = 0; i < width; i++) {
435         GLdouble d = depth[i] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
436         d = CLAMP(d, 0.0, 1.0) * depthMaxF;
437         if (d >= depthMaxF)
438            z[i] = depthMax;
439         else
440            z[i] = (GLuint) d;
441      }
442   }
443}
444
445
446
447/*
448 * TODO: Optimize!!!!
449 */
450static void
451copy_depth_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
452                   GLint width, GLint height,
453                   GLint destx, GLint desty )
454{
455   SWcontext *swrast = SWRAST_CONTEXT(ctx);
456   struct gl_framebuffer *fb = ctx->ReadBuffer;
457   struct gl_renderbuffer *readRb = fb->_DepthBuffer;
458   GLfloat *p, *tmpImage;
459   GLint sy, dy, stepy;
460   GLint j;
461   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
462   GLint overlapping;
463   SWspan span;
464
465   if (!readRb) {
466      /* no readbuffer - OK */
467      return;
468   }
469
470   INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_Z);
471
472   /* Determine if copy should be bottom-to-top or top-to-bottom */
473   if (srcy<desty) {
474      /* top-down  max-to-min */
475      sy = srcy + height - 1;
476      dy = desty + height - 1;
477      stepy = -1;
478   }
479   else {
480      /* bottom-up  min-to-max */
481      sy = srcy;
482      dy = desty;
483      stepy = 1;
484   }
485
486   if (ctx->DrawBuffer == ctx->ReadBuffer) {
487      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
488                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
489   }
490   else {
491      overlapping = GL_FALSE;
492   }
493
494   _swrast_span_default_color(ctx, &span);
495   if (ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)
496      _swrast_span_default_secondary_color(ctx, &span);
497   if (swrast->_FogEnabled)
498      _swrast_span_default_fog(ctx, &span);
499
500   if (overlapping) {
501      GLint ssy = sy;
502      tmpImage = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat));
503      if (!tmpImage) {
504         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
505         return;
506      }
507      p = tmpImage;
508      for (j = 0; j < height; j++, ssy += stepy) {
509         _swrast_read_depth_span_float(ctx, readRb, width, srcx, ssy, p);
510         p += width;
511      }
512      p = tmpImage;
513   }
514   else {
515      tmpImage = NULL;  /* silence compiler warning */
516      p = NULL;
517   }
518
519   for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
520      GLfloat depth[MAX_WIDTH];
521      /* get depth values */
522      if (overlapping) {
523         _mesa_memcpy(depth, p, width * sizeof(GLfloat));
524         p += width;
525      }
526      else {
527         _swrast_read_depth_span_float(ctx, readRb, width, srcx, sy, depth);
528      }
529
530      /* apply scale and bias */
531      scale_and_bias_z(ctx, width, depth, span.array->z);
532
533      /* write depth values */
534      span.x = destx;
535      span.y = dy;
536      span.end = width;
537      if (fb->Visual.rgbMode) {
538         if (zoom)
539            _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span,
540                                           span.array->rgba);
541         else
542            _swrast_write_rgba_span(ctx, &span);
543      }
544      else {
545         if (zoom)
546            _swrast_write_zoomed_index_span(ctx, destx, desty, &span);
547         else
548            _swrast_write_index_span(ctx, &span);
549      }
550   }
551
552   if (overlapping)
553      _mesa_free(tmpImage);
554}
555
556
557
558static void
559copy_stencil_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
560                     GLint width, GLint height,
561                     GLint destx, GLint desty )
562{
563   struct gl_framebuffer *fb = ctx->ReadBuffer;
564   struct gl_renderbuffer *rb = fb->_StencilBuffer;
565   GLint sy, dy, stepy;
566   GLint j;
567   GLstencil *p, *tmpImage;
568   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
569   GLint overlapping;
570
571   if (!rb) {
572      /* no readbuffer - OK */
573      return;
574   }
575
576   /* Determine if copy should be bottom-to-top or top-to-bottom */
577   if (srcy < desty) {
578      /* top-down  max-to-min */
579      sy = srcy + height - 1;
580      dy = desty + height - 1;
581      stepy = -1;
582   }
583   else {
584      /* bottom-up  min-to-max */
585      sy = srcy;
586      dy = desty;
587      stepy = 1;
588   }
589
590   if (ctx->DrawBuffer == ctx->ReadBuffer) {
591      overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
592                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
593   }
594   else {
595      overlapping = GL_FALSE;
596   }
597
598   if (overlapping) {
599      GLint ssy = sy;
600      tmpImage = (GLstencil *) _mesa_malloc(width * height * sizeof(GLstencil));
601      if (!tmpImage) {
602         _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
603         return;
604      }
605      p = tmpImage;
606      for (j = 0; j < height; j++, ssy += stepy) {
607         _swrast_read_stencil_span( ctx, rb, width, srcx, ssy, p );
608         p += width;
609      }
610      p = tmpImage;
611   }
612   else {
613      tmpImage = NULL;  /* silence compiler warning */
614      p = NULL;
615   }
616
617   for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
618      GLstencil stencil[MAX_WIDTH];
619
620      /* Get stencil values */
621      if (overlapping) {
622         _mesa_memcpy(stencil, p, width * sizeof(GLstencil));
623         p += width;
624      }
625      else {
626         _swrast_read_stencil_span( ctx, rb, width, srcx, sy, stencil );
627      }
628
629      _mesa_apply_stencil_transfer_ops(ctx, width, stencil);
630
631      /* Write stencil values */
632      if (zoom) {
633         _swrast_write_zoomed_stencil_span(ctx, destx, desty, width,
634                                           destx, dy, stencil);
635      }
636      else {
637         _swrast_write_stencil_span( ctx, width, destx, dy, stencil );
638      }
639   }
640
641   if (overlapping)
642      _mesa_free(tmpImage);
643}
644
645
646/**
647 * This isn't terribly efficient.  If a driver really has combined
648 * depth/stencil buffers the driver should implement an optimized
649 * CopyPixels function.
650 */
651static void
652copy_depth_stencil_pixels(GLcontext *ctx,
653                          const GLint srcX, const GLint srcY,
654                          const GLint width, const GLint height,
655                          const GLint destX, const GLint destY)
656{
657   struct gl_renderbuffer *stencilReadRb, *depthReadRb, *depthDrawRb;
658   GLint sy, dy, stepy;
659   GLint j;
660   GLstencil *tempStencilImage = NULL, *stencilPtr = NULL;
661   GLfloat *tempDepthImage = NULL, *depthPtr = NULL;
662   const GLfloat depthScale = ctx->DrawBuffer->_DepthMaxF;
663   const GLuint stencilMask = ctx->Stencil.WriteMask[0];
664   const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
665   const GLboolean scaleOrBias
666      = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
667   GLint overlapping;
668
669   depthDrawRb = ctx->DrawBuffer->_DepthBuffer;
670   depthReadRb = ctx->ReadBuffer->_DepthBuffer;
671   stencilReadRb = ctx->ReadBuffer->_StencilBuffer;
672
673   ASSERT(depthDrawRb);
674   ASSERT(depthReadRb);
675   ASSERT(stencilReadRb);
676
677   /* Determine if copy should be bottom-to-top or top-to-bottom */
678   if (srcY < destY) {
679      /* top-down  max-to-min */
680      sy = srcY + height - 1;
681      dy = destY + height - 1;
682      stepy = -1;
683   }
684   else {
685      /* bottom-up  min-to-max */
686      sy = srcY;
687      dy = destY;
688      stepy = 1;
689   }
690
691   if (ctx->DrawBuffer == ctx->ReadBuffer) {
692      overlapping = regions_overlap(srcX, srcY, destX, destY, width, height,
693                                    ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
694   }
695   else {
696      overlapping = GL_FALSE;
697   }
698
699   if (overlapping) {
700      GLint ssy = sy;
701
702      if (stencilMask != 0x0) {
703         tempStencilImage
704            = (GLstencil *) _mesa_malloc(width * height * sizeof(GLstencil));
705         if (!tempStencilImage) {
706            _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
707            return;
708         }
709
710         /* get copy of stencil pixels */
711         stencilPtr = tempStencilImage;
712         for (j = 0; j < height; j++, ssy += stepy) {
713            _swrast_read_stencil_span(ctx, stencilReadRb,
714                                      width, srcX, ssy, stencilPtr);
715            stencilPtr += width;
716         }
717         stencilPtr = tempStencilImage;
718      }
719
720      if (ctx->Depth.Mask) {
721         tempDepthImage
722            = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat));
723         if (!tempDepthImage) {
724            _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
725            _mesa_free(tempStencilImage);
726            return;
727         }
728
729         /* get copy of depth pixels */
730         depthPtr = tempDepthImage;
731         for (j = 0; j < height; j++, ssy += stepy) {
732            _swrast_read_depth_span_float(ctx, depthReadRb,
733                                          width, srcX, ssy, depthPtr);
734            depthPtr += width;
735         }
736         depthPtr = tempDepthImage;
737      }
738   }
739
740   for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
741      if (stencilMask != 0x0) {
742         GLstencil stencil[MAX_WIDTH];
743
744         /* Get stencil values */
745         if (overlapping) {
746            _mesa_memcpy(stencil, stencilPtr, width * sizeof(GLstencil));
747            stencilPtr += width;
748         }
749         else {
750            _swrast_read_stencil_span(ctx, stencilReadRb,
751                                      width, srcX, sy, stencil);
752         }
753
754         _mesa_apply_stencil_transfer_ops(ctx, width, stencil);
755
756         /* Write values */
757         if (zoom) {
758            _swrast_write_zoomed_stencil_span(ctx, destX, destY, width,
759                                              destX, dy, stencil);
760         }
761         else {
762            _swrast_write_stencil_span( ctx, width, destX, dy, stencil );
763         }
764      }
765
766      if (ctx->Depth.Mask) {
767         GLfloat depth[MAX_WIDTH];
768         GLuint zVals32[MAX_WIDTH];
769         GLushort zVals16[MAX_WIDTH];
770         GLvoid *zVals;
771         GLuint zBytes;
772
773         /* get depth values */
774         if (overlapping) {
775            _mesa_memcpy(depth, depthPtr, width * sizeof(GLfloat));
776            depthPtr += width;
777         }
778         else {
779            _swrast_read_depth_span_float(ctx, depthReadRb,
780                                          width, srcX, sy, depth);
781         }
782
783         /* scale & bias */
784         if (scaleOrBias) {
785            _mesa_scale_and_bias_depth(ctx, width, depth);
786         }
787         /* convert to integer Z values */
788         if (depthDrawRb->DataType == GL_UNSIGNED_SHORT) {
789            GLint k;
790            for (k = 0; k < width; k++)
791               zVals16[k] = (GLushort) (depth[k] * depthScale);
792            zVals = zVals16;
793            zBytes = 2;
794         }
795         else {
796            GLint k;
797            for (k = 0; k < width; k++)
798               zVals32[k] = (GLuint) (depth[k] * depthScale);
799            zVals = zVals32;
800            zBytes = 4;
801         }
802
803         /* Write values */
804         if (zoom) {
805            _swrast_write_zoomed_z_span(ctx, destX, destY, width,
806                                        destX, dy, zVals);
807         }
808         else {
809            _swrast_put_row(ctx, depthDrawRb, width, destX, dy, zVals, zBytes);
810         }
811      }
812   }
813
814   if (tempStencilImage)
815      _mesa_free(tempStencilImage);
816
817   if (tempDepthImage)
818      _mesa_free(tempDepthImage);
819}
820
821
822
823/**
824 * Try to do a fast copy pixels.
825 */
826static GLboolean
827fast_copy_pixels(GLcontext *ctx,
828                 GLint srcX, GLint srcY, GLsizei width, GLsizei height,
829                 GLint dstX, GLint dstY, GLenum type)
830{
831   struct gl_framebuffer *srcFb = ctx->ReadBuffer;
832   struct gl_framebuffer *dstFb = ctx->DrawBuffer;
833   struct gl_renderbuffer *srcRb, *dstRb;
834   GLint row, yStep;
835
836   if (SWRAST_CONTEXT(ctx)->_RasterMask != 0x0 ||
837       ctx->Pixel.ZoomX != 1.0F ||
838       ctx->Pixel.ZoomY != 1.0F ||
839       ctx->_ImageTransferState) {
840      /* can't handle these */
841      return GL_FALSE;
842   }
843
844   if (type == GL_COLOR) {
845      if (dstFb->_NumColorDrawBuffers[0] != 1)
846         return GL_FALSE;
847      srcRb = srcFb->_ColorReadBuffer;
848      dstRb = dstFb->_ColorDrawBuffers[0][0];
849   }
850   else if (type == GL_STENCIL) {
851      srcRb = srcFb->_StencilBuffer;
852      dstRb = dstFb->_StencilBuffer;
853   }
854   else if (type == GL_DEPTH) {
855      srcRb = srcFb->_DepthBuffer;
856      dstRb = dstFb->_DepthBuffer;
857   }
858   else {
859      ASSERT(type == GL_DEPTH_STENCIL_EXT);
860      /* XXX correct? */
861      srcRb = srcFb->Attachment[BUFFER_DEPTH].Renderbuffer;
862      dstRb = dstFb->Attachment[BUFFER_DEPTH].Renderbuffer;
863   }
864
865   /* src and dst renderbuffers must be same format and type */
866   if (!srcRb || !dstRb ||
867       srcRb->DataType != dstRb->DataType ||
868       srcRb->_BaseFormat != dstRb->_BaseFormat) {
869      return GL_FALSE;
870   }
871
872   /* clipping not supported */
873   if (srcX < 0 || srcX + width > (GLint) srcFb->Width ||
874       srcY < 0 || srcY + height > (GLint) srcFb->Height ||
875       dstX < dstFb->_Xmin || dstX + width > dstFb->_Xmax ||
876       dstY < dstFb->_Ymin || dstY + height > dstFb->_Ymax) {
877      return GL_FALSE;
878   }
879
880   /* overlapping src/dst doesn't matter, just determine Y direction */
881   if (srcY < dstY) {
882      /* top-down  max-to-min */
883      srcY = srcY + height - 1;
884      dstY = dstY + height - 1;
885      yStep = -1;
886   }
887   else {
888      /* bottom-up  min-to-max */
889      yStep = 1;
890   }
891
892   for (row = 0; row < height; row++) {
893      GLuint temp[MAX_WIDTH][4];
894      srcRb->GetRow(ctx, srcRb, width, srcX, srcY, temp);
895      dstRb->PutRow(ctx, dstRb, width, dstX, dstY, temp, NULL);
896      srcY += yStep;
897      dstY += yStep;
898   }
899
900   return GL_TRUE;
901}
902
903
904/**
905 * Do software-based glCopyPixels.
906 * By time we get here, all parameters will have been error-checked.
907 */
908void
909_swrast_CopyPixels( GLcontext *ctx,
910		    GLint srcx, GLint srcy, GLsizei width, GLsizei height,
911		    GLint destx, GLint desty, GLenum type )
912{
913   SWcontext *swrast = SWRAST_CONTEXT(ctx);
914   RENDER_START(swrast,ctx);
915
916   if (swrast->NewState)
917      _swrast_validate_derived( ctx );
918
919   if (!fast_copy_pixels(ctx, srcx, srcy, width, height, destx, desty, type)) {
920      switch (type) {
921      case GL_COLOR:
922         if (ctx->Visual.rgbMode) {
923            copy_rgba_pixels( ctx, srcx, srcy, width, height, destx, desty );
924         }
925         else {
926            copy_ci_pixels( ctx, srcx, srcy, width, height, destx, desty );
927         }
928         break;
929      case GL_DEPTH:
930         copy_depth_pixels( ctx, srcx, srcy, width, height, destx, desty );
931         break;
932      case GL_STENCIL:
933         copy_stencil_pixels( ctx, srcx, srcy, width, height, destx, desty );
934         break;
935      case GL_DEPTH_STENCIL_EXT:
936         copy_depth_stencil_pixels(ctx, srcx, srcy, width, height, destx, desty);
937         break;
938      default:
939         _mesa_problem(ctx, "unexpected type in _swrast_CopyPixels");
940      }
941   }
942
943   RENDER_FINISH(swrast,ctx);
944}
945