src/mesa/swrast/s_copypix.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  7.1
   4  *
   5  * Copyright (C) 1999-2007  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 "main/glheader.h"
  27 #include "main/context.h"
  28 #include "main/colormac.h"
  29 #include "main/condrender.h"
  30 #include "main/convolve.h"
  31 #include "main/image.h"
  32 #include "main/macros.h"
  33 #include "main/imports.h"
  34
  35 #include "s_context.h"
  36 #include "s_depth.h"
  37 #include "s_span.h"
  38 #include "s_stencil.h"
  39 #include "s_zoom.h"
  40
  41
  42
  43 /**
  44  * Determine if there's overlap in an image copy.
  45  * This test also compensates for the fact that copies are done from
  46  * bottom to top and overlaps can sometimes be handled correctly
  47  * without making a temporary image copy.
  48  * \return GL_TRUE if the regions overlap, GL_FALSE otherwise.
  49  */
  50 static GLboolean
  51 regions_overlap(GLint srcx, GLint srcy,
  52                 GLint dstx, GLint dsty,
  53                 GLint width, GLint height,
  54                 GLfloat zoomX, GLfloat zoomY)
  55 {
  56    if (zoomX == 1.0 && zoomY == 1.0) {
  57       /* no zoom */
  58       if (srcx >= dstx + width || (srcx + width <= dstx)) {
  59          return GL_FALSE;
  60       }
  61       else if (srcy < dsty) { /* this is OK */
  62          return GL_FALSE;
  63       }
  64       else if (srcy > dsty + height) {
  65          return GL_FALSE;
  66       }
  67       else {
  68          return GL_TRUE;
  69       }
  70    }
  71    else {
  72       /* add one pixel of slop when zooming, just to be safe */
  73       if (srcx > (dstx + ((zoomX > 0.0F) ? (width * zoomX + 1.0F) : 0.0F))) {
  74          /* src is completely right of dest */
  75          return GL_FALSE;
  76       }
  77       else if (srcx + width + 1.0F < dstx + ((zoomX > 0.0F) ? 0.0F : (width * zoomX))) {
  78          /* src is completely left of dest */
  79          return GL_FALSE;
  80       }
  81       else if ((srcy < dsty) && (srcy + height < dsty + (height * zoomY))) {
  82          /* src is completely below dest */
  83          return GL_FALSE;
  84       }
  85       else if ((srcy > dsty) && (srcy + height > dsty + (height * zoomY))) {
  86          /* src is completely above dest */
  87          return GL_FALSE;
  88       }
  89       else {
  90          return GL_TRUE;
  91       }
  92    }
  93 }
  94
  95
  96 /**
  97  * RGBA copypixels with convolution.
  98  */
  99 static void
 100 copy_conv_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
 101                       GLint width, GLint height, GLint destx, GLint desty)
 102 {
 103    GLint row;
 104    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 105    const GLbitfield transferOps = ctx->_ImageTransferState;
 106    const GLboolean sink = (ctx->Pixel.MinMaxEnabled && ctx->MinMax.Sink)
 107       || (ctx->Pixel.HistogramEnabled && ctx->Histogram.Sink);
 108    GLfloat *dest, *tmpImage, *convImage;
 109    SWspan span;
 110
 111    INIT_SPAN(span, GL_BITMAP);
 112    _swrast_span_default_attribs(ctx, &span);
 113    span.arrayMask = SPAN_RGBA;
 114    span.arrayAttribs = FRAG_BIT_COL0;
 115
 116    /* allocate space for GLfloat image */
 117    tmpImage = (GLfloat *) malloc(width * height * 4 * sizeof(GLfloat));
 118    if (!tmpImage) {
 119       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 120       return;
 121    }
 122    convImage = (GLfloat *) malloc(width * height * 4 * sizeof(GLfloat));
 123    if (!convImage) {
 124       free(tmpImage);
 125       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 126       return;
 127    }
 128
 129    /* read source image as float/RGBA */
 130    dest = tmpImage;
 131    for (row = 0; row < height; row++) {
 132       _swrast_read_rgba_span(ctx, ctx->ReadBuffer->_ColorReadBuffer,
 133                              width, srcx, srcy + row, GL_FLOAT, dest);
 134       dest += 4 * width;
 135    }
 136
 137    /* do the image transfer ops which preceed convolution */
 138    for (row = 0; row < height; row++) {
 139       GLfloat (*rgba)[4] = (GLfloat (*)[4]) (tmpImage + row * width * 4);
 140       _mesa_apply_rgba_transfer_ops(ctx,
 141                                     transferOps & IMAGE_PRE_CONVOLUTION_BITS,
 142                                     width, rgba);
 143    }
 144
 145    /* do convolution */
 146    if (ctx->Pixel.Convolution2DEnabled) {
 147       _mesa_convolve_2d_image(ctx, &width, &height, tmpImage, convImage);
 148    }
 149    else {
 150       ASSERT(ctx->Pixel.Separable2DEnabled);
 151       _mesa_convolve_sep_image(ctx, &width, &height, tmpImage, convImage);
 152    }
 153    free(tmpImage);
 154
 155    /* do remaining post-convolution image transfer ops */
 156    for (row = 0; row < height; row++) {
 157       GLfloat (*rgba)[4] = (GLfloat (*)[4]) (convImage + row * width * 4);
 158       _mesa_apply_rgba_transfer_ops(ctx,
 159                                     transferOps & IMAGE_POST_CONVOLUTION_BITS,
 160                                     width, rgba);
 161    }
 162
 163    if (!sink) {
 164       /* write the new image */
 165       for (row = 0; row < height; row++) {
 166          const GLfloat *src = convImage + row * width * 4;
 167          GLfloat *rgba = (GLfloat *) span.array->attribs[FRAG_ATTRIB_COL0];
 168
 169          /* copy convolved colors into span array */
 170          memcpy(rgba, src, width * 4 * sizeof(GLfloat));
 171
 172          /* write span */
 173          span.x = destx;
 174          span.y = desty + row;
 175          span.end = width;
 176          span.array->ChanType = GL_FLOAT;
 177          if (zoom) {
 178             _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
 179          }
 180          else {
 181             _swrast_write_rgba_span(ctx, &span);
 182          }
 183       }
 184       /* restore this */
 185       span.array->ChanType = CHAN_TYPE;
 186    }
 187
 188    free(convImage);
 189 }
 190
 191
 192 /**
 193  * RGBA copypixels
 194  */
 195 static void
 196 copy_rgba_pixels(GLcontext *ctx, GLint srcx, GLint srcy,
 197                  GLint width, GLint height, GLint destx, GLint desty)
 198 {
 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    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 222       overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
 223                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 224    }
 225    else {
 226       overlapping = GL_FALSE;
 227    }
 228
 229    /* Determine if copy should be done bottom-to-top or top-to-bottom */
 230    if (!overlapping && srcy < desty) {
 231       /* top-down  max-to-min */
 232       sy = srcy + height - 1;
 233       dy = desty + height - 1;
 234       stepy = -1;
 235    }
 236    else {
 237       /* bottom-up  min-to-max */
 238       sy = srcy;
 239       dy = desty;
 240       stepy = 1;
 241    }
 242
 243    INIT_SPAN(span, GL_BITMAP);
 244    _swrast_span_default_attribs(ctx, &span);
 245    span.arrayMask = SPAN_RGBA;
 246    span.arrayAttribs = FRAG_BIT_COL0; /* we'll fill in COL0 attrib values */
 247
 248    if (overlapping) {
 249       tmpImage = (GLfloat *) malloc(width * height * sizeof(GLfloat) * 4);
 250       if (!tmpImage) {
 251          _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
 252          return;
 253       }
 254       /* read the source image as RGBA/float */
 255       p = tmpImage;
 256       for (row = 0; row < height; row++) {
 257          _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
 258                                  width, srcx, sy + row, GL_FLOAT, p );
 259          p += width * 4;
 260       }
 261       p = tmpImage;
 262    }
 263    else {
 264       tmpImage = NULL;  /* silence compiler warnings */
 265       p = NULL;
 266    }
 267
 268    ASSERT(width < MAX_WIDTH);
 269
 270    for (row = 0; row < height; row++, sy += stepy, dy += stepy) {
 271       GLvoid *rgba = span.array->attribs[FRAG_ATTRIB_COL0];
 272
 273       /* Get row/span of source pixels */
 274       if (overlapping) {
 275          /* get from buffered image */
 276          memcpy(rgba, p, width * sizeof(GLfloat) * 4);
 277          p += width * 4;
 278       }
 279       else {
 280          /* get from framebuffer */
 281          _swrast_read_rgba_span( ctx, ctx->ReadBuffer->_ColorReadBuffer,
 282                                  width, srcx, sy, GL_FLOAT, rgba );
 283       }
 284
 285       if (transferOps) {
 286          _mesa_apply_rgba_transfer_ops(ctx, transferOps, width,
 287                                        (GLfloat (*)[4]) rgba);
 288       }
 289
 290       /* Write color span */
 291       span.x = destx;
 292       span.y = dy;
 293       span.end = width;
 294       span.array->ChanType = GL_FLOAT;
 295       if (zoom) {
 296          _swrast_write_zoomed_rgba_span(ctx, destx, desty, &span, rgba);
 297       }
 298       else {
 299          _swrast_write_rgba_span(ctx, &span);
 300       }
 301    }
 302
 303    span.array->ChanType = CHAN_TYPE; /* restore */
 304
 305    if (overlapping)
 306       free(tmpImage);
 307 }
 308
 309
 310 /**
 311  * Convert floating point Z values to integer Z values with pixel transfer's
 312  * Z scale and bias.
 313  */
 314 static void
 315 scale_and_bias_z(GLcontext *ctx, GLuint width,
 316                  const GLfloat depth[], GLuint z[])
 317 {
 318    const GLuint depthMax = ctx->DrawBuffer->_DepthMax;
 319    GLuint i;
 320
 321    if (depthMax <= 0xffffff &&
 322        ctx->Pixel.DepthScale == 1.0 &&
 323        ctx->Pixel.DepthBias == 0.0) {
 324       /* no scale or bias and no clamping and no worry of overflow */
 325       const GLfloat depthMaxF = ctx->DrawBuffer->_DepthMaxF;
 326       for (i = 0; i < width; i++) {
 327          z[i] = (GLuint) (depth[i] * depthMaxF);
 328       }
 329    }
 330    else {
 331       /* need to be careful with overflow */
 332       const GLdouble depthMaxF = ctx->DrawBuffer->_DepthMaxF;
 333       for (i = 0; i < width; i++) {
 334          GLdouble d = depth[i] * ctx->Pixel.DepthScale + ctx->Pixel.DepthBias;
 335          d = CLAMP(d, 0.0, 1.0) * depthMaxF;
 336          if (d >= depthMaxF)
 337             z[i] = depthMax;
 338          else
 339             z[i] = (GLuint) d;
 340       }
 341    }
 342 }
 343
 344
 345
 346 /*
 347  * TODO: Optimize!!!!
 348  */
 349 static void
 350 copy_depth_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
 351                    GLint width, GLint height,
 352                    GLint destx, GLint desty )
 353 {
 354    struct gl_framebuffer *fb = ctx->ReadBuffer;
 355    struct gl_renderbuffer *readRb = fb->_DepthBuffer;
 356    GLfloat *p, *tmpImage;
 357    GLint sy, dy, stepy;
 358    GLint j;
 359    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 360    GLint overlapping;
 361    SWspan span;
 362
 363    if (!readRb) {
 364       /* no readbuffer - OK */
 365       return;
 366    }
 367
 368    INIT_SPAN(span, GL_BITMAP);
 369    _swrast_span_default_attribs(ctx, &span);
 370    span.arrayMask = SPAN_Z;
 371
 372    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 373       overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
 374                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 375    }
 376    else {
 377       overlapping = GL_FALSE;
 378    }
 379
 380    /* Determine if copy should be bottom-to-top or top-to-bottom */
 381    if (!overlapping && srcy < desty) {
 382       /* top-down  max-to-min */
 383       sy = srcy + height - 1;
 384       dy = desty + height - 1;
 385       stepy = -1;
 386    }
 387    else {
 388       /* bottom-up  min-to-max */
 389       sy = srcy;
 390       dy = desty;
 391       stepy = 1;
 392    }
 393
 394    if (overlapping) {
 395       GLint ssy = sy;
 396       tmpImage = (GLfloat *) malloc(width * height * sizeof(GLfloat));
 397       if (!tmpImage) {
 398          _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
 399          return;
 400       }
 401       p = tmpImage;
 402       for (j = 0; j < height; j++, ssy += stepy) {
 403          _swrast_read_depth_span_float(ctx, readRb, width, srcx, ssy, p);
 404          p += width;
 405       }
 406       p = tmpImage;
 407    }
 408    else {
 409       tmpImage = NULL;  /* silence compiler warning */
 410       p = NULL;
 411    }
 412
 413    for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
 414       GLfloat depth[MAX_WIDTH];
 415       /* get depth values */
 416       if (overlapping) {
 417          memcpy(depth, p, width * sizeof(GLfloat));
 418          p += width;
 419       }
 420       else {
 421          _swrast_read_depth_span_float(ctx, readRb, width, srcx, sy, depth);
 422       }
 423
 424       /* apply scale and bias */
 425       scale_and_bias_z(ctx, width, depth, span.array->z);
 426
 427       /* write depth values */
 428       span.x = destx;
 429       span.y = dy;
 430       span.end = width;
 431       if (zoom)
 432          _swrast_write_zoomed_depth_span(ctx, destx, desty, &span);
 433       else
 434          _swrast_write_rgba_span(ctx, &span);
 435    }
 436
 437    if (overlapping)
 438       free(tmpImage);
 439 }
 440
 441
 442
 443 static void
 444 copy_stencil_pixels( GLcontext *ctx, GLint srcx, GLint srcy,
 445                      GLint width, GLint height,
 446                      GLint destx, GLint desty )
 447 {
 448    struct gl_framebuffer *fb = ctx->ReadBuffer;
 449    struct gl_renderbuffer *rb = fb->_StencilBuffer;
 450    GLint sy, dy, stepy;
 451    GLint j;
 452    GLstencil *p, *tmpImage;
 453    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 454    GLint overlapping;
 455
 456    if (!rb) {
 457       /* no readbuffer - OK */
 458       return;
 459    }
 460
 461    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 462       overlapping = regions_overlap(srcx, srcy, destx, desty, width, height,
 463                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 464    }
 465    else {
 466       overlapping = GL_FALSE;
 467    }
 468
 469    /* Determine if copy should be bottom-to-top or top-to-bottom */
 470    if (!overlapping && srcy < desty) {
 471       /* top-down  max-to-min */
 472       sy = srcy + height - 1;
 473       dy = desty + height - 1;
 474       stepy = -1;
 475    }
 476    else {
 477       /* bottom-up  min-to-max */
 478       sy = srcy;
 479       dy = desty;
 480       stepy = 1;
 481    }
 482
 483    if (overlapping) {
 484       GLint ssy = sy;
 485       tmpImage = (GLstencil *) malloc(width * height * sizeof(GLstencil));
 486       if (!tmpImage) {
 487          _mesa_error( ctx, GL_OUT_OF_MEMORY, "glCopyPixels" );
 488          return;
 489       }
 490       p = tmpImage;
 491       for (j = 0; j < height; j++, ssy += stepy) {
 492          _swrast_read_stencil_span( ctx, rb, width, srcx, ssy, p );
 493          p += width;
 494       }
 495       p = tmpImage;
 496    }
 497    else {
 498       tmpImage = NULL;  /* silence compiler warning */
 499       p = NULL;
 500    }
 501
 502    for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
 503       GLstencil stencil[MAX_WIDTH];
 504
 505       /* Get stencil values */
 506       if (overlapping) {
 507          memcpy(stencil, p, width * sizeof(GLstencil));
 508          p += width;
 509       }
 510       else {
 511          _swrast_read_stencil_span( ctx, rb, width, srcx, sy, stencil );
 512       }
 513
 514       _mesa_apply_stencil_transfer_ops(ctx, width, stencil);
 515
 516       /* Write stencil values */
 517       if (zoom) {
 518          _swrast_write_zoomed_stencil_span(ctx, destx, desty, width,
 519                                            destx, dy, stencil);
 520       }
 521       else {
 522          _swrast_write_stencil_span( ctx, width, destx, dy, stencil );
 523       }
 524    }
 525
 526    if (overlapping)
 527       free(tmpImage);
 528 }
 529
 530
 531 /**
 532  * This isn't terribly efficient.  If a driver really has combined
 533  * depth/stencil buffers the driver should implement an optimized
 534  * CopyPixels function.
 535  */
 536 static void
 537 copy_depth_stencil_pixels(GLcontext *ctx,
 538                           const GLint srcX, const GLint srcY,
 539                           const GLint width, const GLint height,
 540                           const GLint destX, const GLint destY)
 541 {
 542    struct gl_renderbuffer *stencilReadRb, *depthReadRb, *depthDrawRb;
 543    GLint sy, dy, stepy;
 544    GLint j;
 545    GLstencil *tempStencilImage = NULL, *stencilPtr = NULL;
 546    GLfloat *tempDepthImage = NULL, *depthPtr = NULL;
 547    const GLfloat depthScale = ctx->DrawBuffer->_DepthMaxF;
 548    const GLuint stencilMask = ctx->Stencil.WriteMask[0];
 549    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0F || ctx->Pixel.ZoomY != 1.0F;
 550    const GLboolean scaleOrBias
 551       = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
 552    GLint overlapping;
 553
 554    depthDrawRb = ctx->DrawBuffer->_DepthBuffer;
 555    depthReadRb = ctx->ReadBuffer->_DepthBuffer;
 556    stencilReadRb = ctx->ReadBuffer->_StencilBuffer;
 557
 558    ASSERT(depthDrawRb);
 559    ASSERT(depthReadRb);
 560    ASSERT(stencilReadRb);
 561
 562    if (ctx->DrawBuffer == ctx->ReadBuffer) {
 563       overlapping = regions_overlap(srcX, srcY, destX, destY, width, height,
 564                                     ctx->Pixel.ZoomX, ctx->Pixel.ZoomY);
 565    }
 566    else {
 567       overlapping = GL_FALSE;
 568    }
 569
 570    /* Determine if copy should be bottom-to-top or top-to-bottom */
 571    if (!overlapping && srcY < destY) {
 572       /* top-down  max-to-min */
 573       sy = srcY + height - 1;
 574       dy = destY + height - 1;
 575       stepy = -1;
 576    }
 577    else {
 578       /* bottom-up  min-to-max */
 579       sy = srcY;
 580       dy = destY;
 581       stepy = 1;
 582    }
 583
 584    if (overlapping) {
 585       GLint ssy = sy;
 586
 587       if (stencilMask != 0x0) {
 588          tempStencilImage
 589             = (GLstencil *) malloc(width * height * sizeof(GLstencil));
 590          if (!tempStencilImage) {
 591             _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 592             return;
 593          }
 594
 595          /* get copy of stencil pixels */
 596          stencilPtr = tempStencilImage;
 597          for (j = 0; j < height; j++, ssy += stepy) {
 598             _swrast_read_stencil_span(ctx, stencilReadRb,
 599                                       width, srcX, ssy, stencilPtr);
 600             stencilPtr += width;
 601          }
 602          stencilPtr = tempStencilImage;
 603       }
 604
 605       if (ctx->Depth.Mask) {
 606          tempDepthImage
 607             = (GLfloat *) malloc(width * height * sizeof(GLfloat));
 608          if (!tempDepthImage) {
 609             _mesa_error(ctx, GL_OUT_OF_MEMORY, "glCopyPixels");
 610             free(tempStencilImage);
 611             return;
 612          }
 613
 614          /* get copy of depth pixels */
 615          depthPtr = tempDepthImage;
 616          for (j = 0; j < height; j++, ssy += stepy) {
 617             _swrast_read_depth_span_float(ctx, depthReadRb,
 618                                           width, srcX, ssy, depthPtr);
 619             depthPtr += width;
 620          }
 621          depthPtr = tempDepthImage;
 622       }
 623    }
 624
 625    for (j = 0; j < height; j++, sy += stepy, dy += stepy) {
 626       if (stencilMask != 0x0) {
 627          GLstencil stencil[MAX_WIDTH];
 628
 629          /* Get stencil values */
 630          if (overlapping) {
 631             memcpy(stencil, stencilPtr, width * sizeof(GLstencil));
 632             stencilPtr += width;
 633          }
 634          else {
 635             _swrast_read_stencil_span(ctx, stencilReadRb,
 636                                       width, srcX, sy, stencil);
 637          }
 638
 639          _mesa_apply_stencil_transfer_ops(ctx, width, stencil);
 640
 641          /* Write values */
 642          if (zoom) {
 643             _swrast_write_zoomed_stencil_span(ctx, destX, destY, width,
 644                                               destX, dy, stencil);
 645          }
 646          else {
 647             _swrast_write_stencil_span( ctx, width, destX, dy, stencil );
 648          }
 649       }
 650
 651       if (ctx->Depth.Mask) {
 652          GLfloat depth[MAX_WIDTH];
 653          GLuint zVals32[MAX_WIDTH];
 654          GLushort zVals16[MAX_WIDTH];
 655          GLvoid *zVals;
 656          GLuint zBytes;
 657
 658          /* get depth values */
 659          if (overlapping) {
 660             memcpy(depth, depthPtr, width * sizeof(GLfloat));
 661             depthPtr += width;
 662          }
 663          else {
 664             _swrast_read_depth_span_float(ctx, depthReadRb,
 665                                           width, srcX, sy, depth);
 666          }
 667
 668          /* scale & bias */
 669          if (scaleOrBias) {
 670             _mesa_scale_and_bias_depth(ctx, width, depth);
 671          }
 672          /* convert to integer Z values */
 673          if (depthDrawRb->DataType == GL_UNSIGNED_SHORT) {
 674             GLint k;
 675             for (k = 0; k < width; k++)
 676                zVals16[k] = (GLushort) (depth[k] * depthScale);
 677             zVals = zVals16;
 678             zBytes = 2;
 679          }
 680          else {
 681             GLint k;
 682             for (k = 0; k < width; k++)
 683                zVals32[k] = (GLuint) (depth[k] * depthScale);
 684             zVals = zVals32;
 685             zBytes = 4;
 686          }
 687
 688          /* Write values */
 689          if (zoom) {
 690             _swrast_write_zoomed_z_span(ctx, destX, destY, width,
 691                                         destX, dy, zVals);
 692          }
 693          else {
 694             _swrast_put_row(ctx, depthDrawRb, width, destX, dy, zVals, zBytes);
 695          }
 696       }
 697    }
 698
 699    if (tempStencilImage)
 700       free(tempStencilImage);
 701
 702    if (tempDepthImage)
 703       free(tempDepthImage);
 704 }
 705
 706
 707
 708 /**
 709  * Try to do a fast copy pixels.
 710  */
 711 static GLboolean
 712 fast_copy_pixels(GLcontext *ctx,
 713                  GLint srcX, GLint srcY, GLsizei width, GLsizei height,
 714                  GLint dstX, GLint dstY, GLenum type)
 715 {
 716    struct gl_framebuffer *srcFb = ctx->ReadBuffer;
 717    struct gl_framebuffer *dstFb = ctx->DrawBuffer;
 718    struct gl_renderbuffer *srcRb, *dstRb;
 719    GLint row, yStep;
 720
 721    if (SWRAST_CONTEXT(ctx)->_RasterMask != 0x0 ||
 722        ctx->Pixel.ZoomX != 1.0F ||
 723        ctx->Pixel.ZoomY != 1.0F ||
 724        ctx->_ImageTransferState) {
 725       /* can't handle these */
 726       return GL_FALSE;
 727    }
 728
 729    if (type == GL_COLOR) {
 730       if (dstFb->_NumColorDrawBuffers != 1)
 731          return GL_FALSE;
 732       srcRb = srcFb->_ColorReadBuffer;
 733       dstRb = dstFb->_ColorDrawBuffers[0];
 734    }
 735    else if (type == GL_STENCIL) {
 736       srcRb = srcFb->_StencilBuffer;
 737       dstRb = dstFb->_StencilBuffer;
 738    }
 739    else if (type == GL_DEPTH) {
 740       srcRb = srcFb->_DepthBuffer;
 741       dstRb = dstFb->_DepthBuffer;
 742    }
 743    else {
 744       ASSERT(type == GL_DEPTH_STENCIL_EXT);
 745       /* XXX correct? */
 746       srcRb = srcFb->Attachment[BUFFER_DEPTH].Renderbuffer;
 747       dstRb = dstFb->Attachment[BUFFER_DEPTH].Renderbuffer;
 748    }
 749
 750    /* src and dst renderbuffers must be same format and type */
 751    if (!srcRb || !dstRb ||
 752        srcRb->DataType != dstRb->DataType ||
 753        srcRb->_BaseFormat != dstRb->_BaseFormat) {
 754       return GL_FALSE;
 755    }
 756
 757    /* clipping not supported */
 758    if (srcX < 0 || srcX + width > (GLint) srcFb->Width ||
 759        srcY < 0 || srcY + height > (GLint) srcFb->Height ||
 760        dstX < dstFb->_Xmin || dstX + width > dstFb->_Xmax ||
 761        dstY < dstFb->_Ymin || dstY + height > dstFb->_Ymax) {
 762       return GL_FALSE;
 763    }
 764
 765    /* overlapping src/dst doesn't matter, just determine Y direction */
 766    if (srcY < dstY) {
 767       /* top-down  max-to-min */
 768       srcY = srcY + height - 1;
 769       dstY = dstY + height - 1;
 770       yStep = -1;
 771    }
 772    else {
 773       /* bottom-up  min-to-max */
 774       yStep = 1;
 775    }
 776
 777    for (row = 0; row < height; row++) {
 778       GLuint temp[MAX_WIDTH][4];
 779       srcRb->GetRow(ctx, srcRb, width, srcX, srcY, temp);
 780       dstRb->PutRow(ctx, dstRb, width, dstX, dstY, temp, NULL);
 781       srcY += yStep;
 782       dstY += yStep;
 783    }
 784
 785    return GL_TRUE;
 786 }
 787
 788
 789 /**
 790  * Do software-based glCopyPixels.
 791  * By time we get here, all parameters will have been error-checked.
 792  */
 793 void
 794 _swrast_CopyPixels( GLcontext *ctx,
 795                     GLint srcx, GLint srcy, GLsizei width, GLsizei height,
 796                     GLint destx, GLint desty, GLenum type )
 797 {
 798    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 799    swrast_render_start(ctx);
 800
 801    if (!_mesa_check_conditional_render(ctx))
 802       return; /* don't copy */
 803
 804    if (swrast->NewState)
 805       _swrast_validate_derived( ctx );
 806
 807    if (!fast_copy_pixels(ctx, srcx, srcy, width, height, destx, desty, type)) {
 808       switch (type) {
 809       case GL_COLOR:
 810          copy_rgba_pixels( ctx, srcx, srcy, width, height, destx, desty );
 811          break;
 812       case GL_DEPTH:
 813          copy_depth_pixels( ctx, srcx, srcy, width, height, destx, desty );
 814          break;
 815       case GL_STENCIL:
 816          copy_stencil_pixels( ctx, srcx, srcy, width, height, destx, desty );
 817          break;
 818       case GL_DEPTH_STENCIL_EXT:
 819          copy_depth_stencil_pixels(ctx, srcx, srcy, width, height, destx, desty);
 820          break;
 821       default:
 822          _mesa_problem(ctx, "unexpected type in _swrast_CopyPixels");
 823       }
 824    }
 825
 826    swrast_render_finish(ctx);
 827 }