src/mesa/swrast/s_copypix.c

   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  */
  51 static GLboolean
  52 regions_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  */
  93 static void
  94 copy_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
 113
 114    /* allocate space for GLfloat image */
 115    tmpImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
 116    if (!tmpImage) {
 117       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 118       return;
 119    }
 120    convImage = (GLfloat *) _mesa_malloc(width * height * 4 * sizeof(GLfloat));
 121    if (!convImage) {
 122       _mesa_free(tmpImage);
 123       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 124       return;
 125    }
 126
 127    /* read source image as float/RGBA */
 128    dest = tmpImage;
 129    for (row = 0; row < height; row++) {
 130       _swrast_read_rgba_span(ctx, ctx->ReadBuffer->_ColorReadBuffer,
 131                              width, srcx, srcy + row, GL_FLOAT, dest);
 132       dest += 4 * width;
 133    }
 134
 135    /* do the image transfer ops which preceed convolution */
 136    for (row = 0; row < height; row++) {
 137       GLfloat (*rgba)[4] = (GLfloat (*)[4]) (tmpImage + row * width * 4);
 138       _mesa_apply_rgba_transfer_ops(ctx,
 139                                     transferOps & IMAGE_PRE_CONVOLUTION_BITS,
 140                                     width, rgba);
 141    }
 142
 143    /* do convolution */
 144    if (ctx->Pixel.Convolution2DEnabled) {
 145       _mesa_convolve_2d_image(ctx, &width, &height, tmpImage, convImage);
 146    }
 147    else {
 148       ASSERT(ctx->Pixel.Separable2DEnabled);
 149       _mesa_convolve_sep_image(ctx, &width, &height, tmpImage, convImage);
 150    }
 151    _mesa_free(tmpImage);
 152
 153    /* do remaining post-convolution image transfer ops */
 154    for (row = 0; row < height; row++) {
 155       GLfloat (*rgba)[4] = (GLfloat (*)[4]) (convImage + row * width * 4);
 156       _mesa_apply_rgba_transfer_ops(ctx,
 157                                     transferOps & IMAGE_POST_CONVOLUTION_BITS,
 158                                     width, rgba);
 159    }
 160
 161    if (!sink) {
 162       /* write the new image */
 163       for (row = 0; row < height; row++) {
 164          const GLfloat *src = convImage + row * width * 4;
 165          GLvoid *rgba = span.array->color.sz1.rgba; /* row storage */
 166
 167          /* copy convolved colors into span array */
 168          _mesa_memcpy(rgba, src, width * 4 * sizeof(GLfloat));
 169
 170          /* write span */
 171          span.x = destx;
 172          span.y = desty + row;
 173          span.end = width;
 174          span.array->ChanType = GL_FLOAT;
 175          if (zoom) {
 176             _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
 177          }
 178          else {
 179             _swrast_write_rgba_span(ctx, &span);
 180          }
 181       }
 182       /* restore this */
 183       span.array->ChanType = CHAN_TYPE;
 184    }
 185
 186    _mesa_free(convImage);
 187 }
 188
 189
 190 /**
 191  * RGBA copypixels
 192  */
 193 static void
 194 copy_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
 195                  GLint width, GLint height, GLint destx, GLint desty)
 196 {
 197    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 198    GLfloat *tmpImage, *p;
 199    GLint sy, dy, stepy, row;
 200    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 201    GLint overlapping;
 202    const GLuint transferOps = ctx->_ImageTransferState;
 203    SWspan span;
 204
 205    if (!ctx->ReadBuffer->_ColorReadBuffer) {
 206       /* no readbuffer - OK */
 207       return;
 208    }
 209
 210    if (ctx->Pixel.Convolution2DEnabled || ctx->Pixel.Separable2DEnabled) {
 211       copy_conv_rgba_pixels(ctx, srcx, srcy, width, height, destx, desty);
 212       return;
 213    }
 214
 215    /* Determine if copy should be done bottom-to-top or top-to-bottom */
 216    if (srcy < desty) {
 217       /* top-down  max-to-min */
 218       sy = srcy + height - 1;
 219       dy = desty + height - 1;
 220       stepy = -1;
 221    }
 222    else {
 223       /* bottom-up  min-to-max */
 224       sy = srcy;
 225       dy = desty;
 226       stepy = 1;
 227    }
 228
 229    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 230       overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
 231                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 232    }
 233    else {
 234       overlapping = GL_FALSE;
 235    }
 236
 237    INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_RGBA);
 238    if (ctx->Depth.Test)
 239       _swrast_span_default_z(ctx, &span);
 240    if (swrast->_FogEnabled)
 241       _swrast_span_default_fog(ctx, &span);
 242
 243    if (overlapping) {
 244       tmpImage = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat) * 4);
 245       if (!tmpImage) {
 246          _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
 247          return;
 248       }
 249       /* read the source image as RGBA/float */
 250       p = tmpImage;
 251       for (row = 0; row < height; row++) {
 252          _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
 253                                  width, srcx, sy + row, GL_FLOAT, p );
 254          p += width * 4;
 255       }
 256       p = tmpImage;
 257    }
 258    else {
 259       tmpImage = NULL;  /* silence compiler warnings */
 260       p = NULL;
 261    }
 262
 263    ASSERT(width < MAX_WIDTH);
 264
 265    for (row = 0; row < height; row++, sy += stepy, dy += stepy) {
 266       GLvoid *rgba = span.array->color.sz4.rgba;
 267
 268       /* Get row/span of source pixels */
 269       if (overlapping) {
 270          /* get from buffered image */
 271          _mesa_memcpy(rgba, p, width * sizeof(GLfloat) * 4);
 272          p += width * 4;
 273       }
 274       else {
 275          /* get from framebuffer */
 276          _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
 277                                  width, srcx, sy, GL_FLOAT, rgba );
 278       }
 279
 280       if (transferOps) {
 281          _mesa_apply_rgba_transfer_ops(ctx, transferOps, width,
 282                                        (GLfloat (*)[4]) rgba);
 283       }
 284
 285       /* Write color span */
 286       span.x = destx;
 287       span.y = dy;
 288       span.end = width;
 289       span.array->ChanType = GL_FLOAT;
 290       if (zoom) {
 291          _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
 292       }
 293       else {
 294          _swrast_write_rgba_span(ctx, &span);
 295       }
 296    }
 297
 298    span.array->ChanType = CHAN_TYPE; /* restore */
 299
 300    if (overlapping)
 301       _mesa_free(tmpImage);
 302 }
 303
 304
 305 static void
 306 copy_ci_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
 307                 GLint width, GLint height,
 308                 GLint destx, GLint desty )
 309 {
 310    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 311    GLuint *tmpImage,*p;
 312    GLint sy, dy, stepy;
 313    GLint j;
 314    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 315    GLint overlapping;
 316    SWspan span;
 317
 318    if (!ctx->ReadBuffer->_ColorReadBuffer) {
 319       /* no readbuffer - OK */
 320       return;
 321    }
 322
 323    INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_INDEX);
 324
 325    /* Determine if copy should be bottom-to-top or top-to-bottom */
 326    if (srcy<desty) {
 327       /* top-down  max-to-min */
 328       sy = srcy + height - 1;
 329       dy = desty + height - 1;
 330       stepy = -1;
 331    }
 332    else {
 333       /* bottom-up  min-to-max */
 334       sy = srcy;
 335       dy = desty;
 336       stepy = 1;
 337    }
 338
 339    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 340       overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
 341                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 342    }
 343    else {
 344       overlapping = GL_FALSE;
 345    }
 346
 347    if (ctx->Depth.Test)
 348       _swrast_span_default_z(ctx, &span);
 349    if (swrast->_FogEnabled)
 350       _swrast_span_default_fog(ctx, &span);
 351
 352    if (overlapping) {
 353       GLint ssy = sy;
 354       tmpImage = (GLuint *) _mesa_malloc(width * height * sizeof(GLuint));
 355       if (!tmpImage) {
 356          _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
 357          return;
 358       }
 359       /* read the image */
 360       p = tmpImage;
 361       for (j = 0; j < height; j++, ssy += stepy) {
 362          _swrast_read_index_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
 363                                   width, srcx, ssy, p );
 364          p += width;
 365       }
 366       p = tmpImage;
 367    }
 368    else {
 369       tmpImage = NULL;  /* silence compiler warning */
 370       p = NULL;
 371    }
 372
 373    for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
 374       /* Get color indexes */
 375       if (overlapping) {
 376          _mesa_memcpy(span.array->index, p, width * sizeof(GLuint));
 377          p += width;
 378       }
 379       else {
 380          _swrast_read_index_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
 381                                   width, srcx, sy, span.array->index );
 382       }
 383
 384       if (ctx->_ImageTransferState)
 385          _mesa_apply_ci_transfer_ops(ctx, ctx->_ImageTransferState,
 386                                      width, span.array->index);
 387
 388       /* write color indexes */
 389       span.x = destx;
 390       span.y = dy;
 391       span.end = width;
 392       if (zoom)
 393          _swrast_write_zoomed_index_span(ctx, destx, desty, &span);
 394       else
 395          _swrast_write_index_span(ctx, &span);
 396    }
 397
 398    if (overlapping)
 399       _mesa_free(tmpImage);
 400 }
 401
 402
 403 /**
 404  * Convert floating point Z values to integer Z values with pixel transfer's
 405  * Z scale and bias.
 406  */
 407 static void
 408 scale_and_bias_z(GLcontext *ctx, GLuint width,
 409                  const GLfloat depth[], GLuint z[])
 410 {
 411    const GLuint depthMax = ctx->DrawBuffer->_DepthMax;
 412    GLuint i;
 413
 414    if (depthMax <= 0xffffff &&
 415        ctx->Pixel.DepthScale == 1.0 &&
 416        ctx->Pixel.DepthBias == 0.0) {
 417       /* no scale or bias and no clamping and no worry of overflow */
 418       const GLfloat depthMaxF = ctx->DrawBuffer->_DepthMaxF;
 419       for (i = 0; i < width; i++) {
 420          z[i] = (GLuint) (depth[i] * depthMaxF);
 421       }
 422    }
 423    else {
 424       /* need to be careful with overflow */
 425       const GLdouble depthMaxF = ctx->DrawBuffer->_DepthMaxF;
 426       for (i = 0; i < width; i++) {
 427          GLdouble d = depth[i] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
 428          d = CLAMP(d, 0.0, 1.0) * depthMaxF;
 429          if (d >= depthMaxF)
 430             z[i] = depthMax;
 431          else
 432             z[i] = (GLuint) d;
 433       }
 434    }
 435 }
 436
 437
 438
 439 /*
 440  * TODO: Optimize!!!!
 441  */
 442 static void
 443 copy_depth_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
 444                    GLint width, GLint height,
 445                    GLint destx, GLint desty )
 446 {
 447    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 448    struct gl_framebuffer *fb = ctx->ReadBuffer;
 449    struct gl_renderbuffer *readRb = fb->_DepthBuffer;
 450    GLfloat *p, *tmpImage;
 451    GLint sy, dy, stepy;
 452    GLint j;
 453    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 454    GLint overlapping;
 455    SWspan span;
 456
 457    if (!readRb) {
 458       /* no readbuffer - OK */
 459       return;
 460    }
 461
 462    INIT_SPAN(span, GL_BITMAP, 0, 0, SPAN_Z);
 463
 464    /* Determine if copy should be bottom-to-top or top-to-bottom */
 465    if (srcy<desty) {
 466       /* top-down  max-to-min */
 467       sy = srcy + height - 1;
 468       dy = desty + height - 1;
 469       stepy = -1;
 470    }
 471    else {
 472       /* bottom-up  min-to-max */
 473       sy = srcy;
 474       dy = desty;
 475       stepy = 1;
 476    }
 477
 478    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 479       overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
 480                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 481    }
 482    else {
 483       overlapping = GL_FALSE;
 484    }
 485
 486    _swrast_span_default_color(ctx, &span);
 487    if (swrast->_FogEnabled)
 488       _swrast_span_default_fog(ctx, &span);
 489
 490    if (overlapping) {
 491       GLint ssy = sy;
 492       tmpImage = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat));
 493       if (!tmpImage) {
 494          _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
 495          return;
 496       }
 497       p = tmpImage;
 498       for (j = 0; j < height; j++, ssy += stepy) {
 499          _swrast_read_depth_span_float(ctx, readRb, width, srcx, ssy, p);
 500          p += width;
 501       }
 502       p = tmpImage;
 503    }
 504    else {
 505       tmpImage = NULL;  /* silence compiler warning */
 506       p = NULL;
 507    }
 508
 509    for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
 510       GLfloat depth[MAX_WIDTH];
 511       /* get depth values */
 512       if (overlapping) {
 513          _mesa_memcpy(depth, p, width * sizeof(GLfloat));
 514          p += width;
 515       }
 516       else {
 517          _swrast_read_depth_span_float(ctx, readRb, width, srcx, sy, depth);
 518       }
 519
 520       /* apply scale and bias */
 521       scale_and_bias_z(ctx, width, depth, span.array->z);
 522
 523       /* write depth values */
 524       span.x = destx;
 525       span.y = dy;
 526       span.end = width;
 527       if (fb->Visual.rgbMode) {
 528          if (zoom)
 529             _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span,
 530                                            span.array->rgba);
 531          else
 532             _swrast_write_rgba_span(ctx, &span);
 533       }
 534       else {
 535          if (zoom)
 536             _swrast_write_zoomed_index_span(ctx, destx, desty, &span);
 537          else
 538             _swrast_write_index_span(ctx, &span);
 539       }
 540    }
 541
 542    if (overlapping)
 543       _mesa_free(tmpImage);
 544 }
 545
 546
 547
 548 static void
 549 copy_stencil_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
 550                      GLint width, GLint height,
 551                      GLint destx, GLint desty )
 552 {
 553    struct gl_framebuffer *fb = ctx->ReadBuffer;
 554    struct gl_renderbuffer *rb = fb->_StencilBuffer;
 555    GLint sy, dy, stepy;
 556    GLint j;
 557    GLstencil *p, *tmpImage;
 558    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 559    GLint overlapping;
 560
 561    if (!rb) {
 562       /* no readbuffer - OK */
 563       return;
 564    }
 565
 566    /* Determine if copy should be bottom-to-top or top-to-bottom */
 567    if (srcy < desty) {
 568       /* top-down  max-to-min */
 569       sy = srcy + height - 1;
 570       dy = desty + height - 1;
 571       stepy = -1;
 572    }
 573    else {
 574       /* bottom-up  min-to-max */
 575       sy = srcy;
 576       dy = desty;
 577       stepy = 1;
 578    }
 579
 580    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 581       overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
 582                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 583    }
 584    else {
 585       overlapping = GL_FALSE;
 586    }
 587
 588    if (overlapping) {
 589       GLint ssy = sy;
 590       tmpImage = (GLstencil *) _mesa_malloc(width * height * sizeof(GLstencil));
 591       if (!tmpImage) {
 592          _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
 593          return;
 594       }
 595       p = tmpImage;
 596       for (j = 0; j < height; j++, ssy += stepy) {
 597          _swrast_read_stencil_span( ctx, rb, width, srcx, ssy, p );
 598          p += width;
 599       }
 600       p = tmpImage;
 601    }
 602    else {
 603       tmpImage = NULL;  /* silence compiler warning */
 604       p = NULL;
 605    }
 606
 607    for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
 608       GLstencil stencil[MAX_WIDTH];
 609
 610       /* Get stencil values */
 611       if (overlapping) {
 612          _mesa_memcpy(stencil, p, width * sizeof(GLstencil));
 613          p += width;
 614       }
 615       else {
 616          _swrast_read_stencil_span( ctx, rb, width, srcx, sy, stencil );
 617       }
 618
 619       _mesa_apply_stencil_transfer_ops(ctx, width, stencil);
 620
 621       /* Write stencil values */
 622       if (zoom) {
 623          _swrast_write_zoomed_stencil_span(ctx, destx, desty, width,
 624                                            destx, dy, stencil);
 625       }
 626       else {
 627          _swrast_write_stencil_span( ctx, width, destx, dy, stencil );
 628       }
 629    }
 630
 631    if (overlapping)
 632       _mesa_free(tmpImage);
 633 }
 634
 635
 636 /**
 637  * This isn't terribly efficient.  If a driver really has combined
 638  * depth/stencil buffers the driver should implement an optimized
 639  * CopyPixels function.
 640  */
 641 static void
 642 copy_depth_stencil_pixels(GLcontext *ctx,
 643                           const GLint srcX, const GLint srcY,
 644                           const GLint width, const GLint height,
 645                           const GLint destX, const GLint destY)
 646 {
 647    struct gl_renderbuffer *stencilReadRb, *depthReadRb, *depthDrawRb;
 648    GLint sy, dy, stepy;
 649    GLint j;
 650    GLstencil *tempStencilImage = NULL, *stencilPtr = NULL;
 651    GLfloat *tempDepthImage = NULL, *depthPtr = NULL;
 652    const GLfloat depthScale = ctx->DrawBuffer->_DepthMaxF;
 653    const GLuint stencilMask = ctx->Stencil.WriteMask[0];
 654    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 655    const GLboolean scaleOrBias
 656       = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
 657    GLint overlapping;
 658
 659    depthDrawRb = ctx->DrawBuffer->_DepthBuffer;
 660    depthReadRb = ctx->ReadBuffer->_DepthBuffer;
 661    stencilReadRb = ctx->ReadBuffer->_StencilBuffer;
 662
 663    ASSERT(depthDrawRb);
 664    ASSERT(depthReadRb);
 665    ASSERT(stencilReadRb);
 666
 667    /* Determine if copy should be bottom-to-top or top-to-bottom */
 668    if (srcY < destY) {
 669       /* top-down  max-to-min */
 670       sy = srcY + height - 1;
 671       dy = destY + height - 1;
 672       stepy = -1;
 673    }
 674    else {
 675       /* bottom-up  min-to-max */
 676       sy = srcY;
 677       dy = destY;
 678       stepy = 1;
 679    }
 680
 681    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 682       overlapping = regions_overlap(srcX, srcY, destX, destY, width, height,
 683                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 684    }
 685    else {
 686       overlapping = GL_FALSE;
 687    }
 688
 689    if (overlapping) {
 690       GLint ssy = sy;
 691
 692       if (stencilMask != 0x0) {
 693          tempStencilImage
 694             = (GLstencil *) _mesa_malloc(width * height * sizeof(GLstencil));
 695          if (!tempStencilImage) {
 696             _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 697             return;
 698          }
 699
 700          /* get copy of stencil pixels */
 701          stencilPtr = tempStencilImage;
 702          for (j = 0; j < height; j++, ssy += stepy) {
 703             _swrast_read_stencil_span(ctx, stencilReadRb,
 704                                       width, srcX, ssy, stencilPtr);
 705             stencilPtr += width;
 706          }
 707          stencilPtr = tempStencilImage;
 708       }
 709
 710       if (ctx->Depth.Mask) {
 711          tempDepthImage
 712             = (GLfloat *) _mesa_malloc(width * height * sizeof(GLfloat));
 713          if (!tempDepthImage) {
 714             _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 715             _mesa_free(tempStencilImage);
 716             return;
 717          }
 718
 719          /* get copy of depth pixels */
 720          depthPtr = tempDepthImage;
 721          for (j = 0; j < height; j++, ssy += stepy) {
 722             _swrast_read_depth_span_float(ctx, depthReadRb,
 723                                           width, srcX, ssy, depthPtr);
 724             depthPtr += width;
 725          }
 726          depthPtr = tempDepthImage;
 727       }
 728    }
 729
 730    for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
 731       if (stencilMask != 0x0) {
 732          GLstencil stencil[MAX_WIDTH];
 733
 734          /* Get stencil values */
 735          if (overlapping) {
 736             _mesa_memcpy(stencil, stencilPtr, width * sizeof(GLstencil));
 737             stencilPtr += width;
 738          }
 739          else {
 740             _swrast_read_stencil_span(ctx, stencilReadRb,
 741                                       width, srcX, sy, stencil);
 742          }
 743
 744          _mesa_apply_stencil_transfer_ops(ctx, width, stencil);
 745
 746          /* Write values */
 747          if (zoom) {
 748             _swrast_write_zoomed_stencil_span(ctx, destX, destY, width,
 749                                               destX, dy, stencil);
 750          }
 751          else {
 752             _swrast_write_stencil_span( ctx, width, destX, dy, stencil );
 753          }
 754       }
 755
 756       if (ctx->Depth.Mask) {
 757          GLfloat depth[MAX_WIDTH];
 758          GLuint zVals32[MAX_WIDTH];
 759          GLushort zVals16[MAX_WIDTH];
 760          GLvoid *zVals;
 761          GLuint zBytes;
 762
 763          /* get depth values */
 764          if (overlapping) {
 765             _mesa_memcpy(depth, depthPtr, width * sizeof(GLfloat));
 766             depthPtr += width;
 767          }
 768          else {
 769             _swrast_read_depth_span_float(ctx, depthReadRb,
 770                                           width, srcX, sy, depth);
 771          }
 772
 773          /* scale & bias */
 774          if (scaleOrBias) {
 775             _mesa_scale_and_bias_depth(ctx, width, depth);
 776          }
 777          /* convert to integer Z values */
 778          if (depthDrawRb->DataType == GL_UNSIGNED_SHORT) {
 779             GLint k;
 780             for (k = 0; k < width; k++)
 781                zVals16[k] = (GLushort) (depth[k] * depthScale);
 782             zVals = zVals16;
 783             zBytes = 2;
 784          }
 785          else {
 786             GLint k;
 787             for (k = 0; k < width; k++)
 788                zVals32[k] = (GLuint) (depth[k] * depthScale);
 789             zVals = zVals32;
 790             zBytes = 4;
 791          }
 792
 793          /* Write values */
 794          if (zoom) {
 795             _swrast_write_zoomed_z_span(ctx, destX, destY, width,
 796                                         destX, dy, zVals);
 797          }
 798          else {
 799             _swrast_put_row(ctx, depthDrawRb, width, destX, dy, zVals, zBytes);
 800          }
 801       }
 802    }
 803
 804    if (tempStencilImage)
 805       _mesa_free(tempStencilImage);
 806
 807    if (tempDepthImage)
 808       _mesa_free(tempDepthImage);
 809 }
 810
 811
 812
 813 /**
 814  * Try to do a fast copy pixels.
 815  */
 816 static GLboolean
 817 fast_copy_pixels(GLcontext *ctx,
 818                  GLint srcX, GLint srcY, GLsizei width, GLsizei height,
 819                  GLint dstX, GLint dstY, GLenum type)
 820 {
 821    struct gl_framebuffer *srcFb = ctx->ReadBuffer;
 822    struct gl_framebuffer *dstFb = ctx->DrawBuffer;
 823    struct gl_renderbuffer *srcRb, *dstRb;
 824    GLint row, yStep;
 825
 826    if (SWRAST_CONTEXT(ctx)->_RasterMask != 0x0 ||
 827        ctx->Pixel.ZoomX != 1.0F ||
 828        ctx->Pixel.ZoomY != 1.0F ||
 829        ctx->_ImageTransferState) {
 830       /* can't handle these */
 831       return GL_FALSE;
 832    }
 833
 834    if (type == GL_COLOR) {
 835       if (dstFb->_NumColorDrawBuffers[0] != 1)
 836          return GL_FALSE;
 837       srcRb = srcFb->_ColorReadBuffer;
 838       dstRb = dstFb->_ColorDrawBuffers[0][0];
 839    }
 840    else if (type == GL_STENCIL) {
 841       srcRb = srcFb->_StencilBuffer;
 842       dstRb = dstFb->_StencilBuffer;
 843    }
 844    else if (type == GL_DEPTH) {
 845       srcRb = srcFb->_DepthBuffer;
 846       dstRb = dstFb->_DepthBuffer;
 847    }
 848    else if (type == GL_DEPTH_STENCIL_EXT) {
 849       /* XXX correct? */
 850       srcRb = srcFb->Attachment[BUFFER_DEPTH].Renderbuffer;
 851       dstRb = dstFb->Attachment[BUFFER_DEPTH].Renderbuffer;
 852    }
 853
 854    /* src and dst renderbuffers must be same format and type */
 855    if (!srcRb || !dstRb ||
 856        srcRb->DataType != dstRb->DataType ||
 857        srcRb->_BaseFormat != dstRb->_BaseFormat) {
 858       return GL_FALSE;
 859    }
 860
 861    /* clipping not supported */
 862    if (srcX < 0 || srcX + width > srcFb->Width ||
 863        srcY < 0 || srcY + height > srcFb->Width ||
 864        dstX < dstFb->_Xmin || dstX + width > dstFb->_Xmax ||
 865        dstY < dstFb->_Ymin || dstY + height > dstFb->_Ymax) {
 866       return GL_FALSE;
 867    }
 868
 869    /* overlapping src/dst doesn't matter, just determine Y direction */
 870    if (srcY < dstY) {
 871       /* top-down  max-to-min */
 872       srcY = srcY + height - 1;
 873       dstY = dstY + height - 1;
 874       yStep = -1;
 875    }
 876    else {
 877       /* bottom-up  min-to-max */
 878       yStep = 1;
 879    }
 880
 881    for (row = 0; row < height; row++) {
 882       GLuint temp[MAX_WIDTH][4];
 883       srcRb->GetRow(ctx, srcRb, width, srcX, srcY, temp);
 884       dstRb->PutRow(ctx, dstRb, width, dstX, dstY, temp, NULL);
 885       srcY += yStep;
 886       dstY += yStep;
 887    }
 888
 889    return GL_TRUE;
 890 }
 891
 892
 893 /**
 894  * Do software-based glCopyPixels.
 895  * By time we get here, all parameters will have been error-checked.
 896  */
 897 void
 898 _swrast_CopyPixels( GLcontext *ctx,
 899                     GLint srcx, GLint srcy, GLsizei width, GLsizei height,
 900                     GLint destx, GLint desty, GLenum type )
 901 {
 902    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 903    RENDER_START(swrast,ctx);
 904
 905    if (swrast->NewState)
 906       _swrast_validate_derived( ctx );
 907
 908    if (!fast_copy_pixels(ctx, srcx, srcy, width, height, destx, desty, type)) {
 909       switch (type) {
 910       case GL_COLOR:
 911          if (ctx->Visual.rgbMode) {
 912             copy_rgba_pixels( ctx, srcx, srcy, width, height, destx, desty );
 913          }
 914          else {
 915             copy_ci_pixels( ctx, srcx, srcy, width, height, destx, desty );
 916          }
 917          break;
 918       case GL_DEPTH:
 919          copy_depth_pixels( ctx, srcx, srcy, width, height, destx, desty );
 920          break;
 921       case GL_STENCIL:
 922          copy_stencil_pixels( ctx, srcx, srcy, width, height, destx, desty );
 923          break;
 924       case GL_DEPTH_STENCIL_EXT:
 925          copy_depth_stencil_pixels(ctx, srcx, srcy, width, height, destx, desty);
 926          break;
 927       default:
 928          _mesa_problem(ctx, "unexpected type in _swrast_CopyPixels");
 929       }
 930    }
 931
 932    RENDER_FINISH(swrast,ctx);
 933 }