src/mesa/swrast/s_drawpix.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/bufferobj.h"
  28 #include "main/condrender.h"
  29 #include "main/context.h"
  30 #include "main/image.h"
  31 #include "main/imports.h"
  32 #include "main/macros.h"
  33 #include "main/pack.h"
  34 #include "main/pixeltransfer.h"
  35 #include "main/state.h"
  36
  37 #include "s_context.h"
  38 #include "s_span.h"
  39 #include "s_stencil.h"
  40 #include "s_zoom.h"
  41
  42
  43
  44 /**
  45  * Try to do a fast and simple RGB(a) glDrawPixels.
  46  * Return:  GL_TRUE if success, GL_FALSE if slow path must be used instead
  47  */
  48 static GLboolean
  49 fast_draw_rgba_pixels(struct gl_context *ctx, GLint x, GLint y,
  50                       GLsizei width, GLsizei height,
  51                       GLenum format, GLenum type,
  52                       const struct gl_pixelstore_attrib *userUnpack,
  53                       const GLvoid *pixels)
  54 {
  55    const GLint imgX = x, imgY = y;
  56    struct gl_renderbuffer *rb = ctx->DrawBuffer->_ColorDrawBuffers[0];
  57    GLenum rbType;
  58    SWcontext *swrast = SWRAST_CONTEXT(ctx);
  59    SWspan span;
  60    GLboolean simpleZoom;
  61    GLint yStep;  /* +1 or -1 */
  62    struct gl_pixelstore_attrib unpack;
  63    GLint destX, destY, drawWidth, drawHeight; /* post clipping */
  64
  65    if (!rb)
  66       return GL_TRUE; /* no-op */
  67
  68    rbType = rb->DataType;
  69
  70    if ((swrast->_RasterMask & ~CLIP_BIT) ||
  71        ctx->Texture._EnabledCoordUnits ||
  72        userUnpack->SwapBytes ||
  73        ctx->_ImageTransferState) {
  74       /* can't handle any of those conditions */
  75       return GL_FALSE;
  76    }
  77
  78    INIT_SPAN(span, GL_BITMAP);
  79    span.arrayMask = SPAN_RGBA;
  80    span.arrayAttribs = FRAG_BIT_COL0;
  81    _swrast_span_default_attribs(ctx, &span);
  82
  83    /* copy input params since clipping may change them */
  84    unpack = *userUnpack;
  85    destX = x;
  86    destY = y;
  87    drawWidth = width;
  88    drawHeight = height;
  89
  90    /* check for simple zooming and clipping */
  91    if (ctx->Pixel.ZoomX == 1.0F &&
  92        (ctx->Pixel.ZoomY == 1.0F || ctx->Pixel.ZoomY == -1.0F)) {
  93       if (!_mesa_clip_drawpixels(ctx, &destX, &destY,
  94                                  &drawWidth, &drawHeight, &unpack)) {
  95          /* image was completely clipped: no-op, all done */
  96          return GL_TRUE;
  97       }
  98       simpleZoom = GL_TRUE;
  99       yStep = (GLint) ctx->Pixel.ZoomY;
 100       ASSERT(yStep == 1 || yStep == -1);
 101    }
 102    else {
 103       /* non-simple zooming */
 104       simpleZoom = GL_FALSE;
 105       yStep = 1;
 106       if (unpack.RowLength == 0)
 107          unpack.RowLength = width;
 108    }
 109
 110    /*
 111     * Ready to draw!
 112     */
 113
 114    if (format == GL_RGBA && type == rbType) {
 115       const GLubyte *src
 116          = (const GLubyte *) _mesa_image_address2d(&unpack, pixels, width,
 117                                                    height, format, type, 0, 0);
 118       const GLint srcStride = _mesa_image_row_stride(&unpack, width,
 119                                                      format, type);
 120       if (simpleZoom) {
 121          GLint row;
 122          for (row = 0; row < drawHeight; row++) {
 123             rb->PutRow(ctx, rb, drawWidth, destX, destY, src, NULL);
 124             src += srcStride;
 125             destY += yStep;
 126          }
 127       }
 128       else {
 129          /* with zooming */
 130          GLint row;
 131          for (row = 0; row < drawHeight; row++) {
 132             span.x = destX;
 133             span.y = destY + row;
 134             span.end = drawWidth;
 135             span.array->ChanType = rbType;
 136             _swrast_write_zoomed_rgba_span(ctx, imgX, imgY, &span, src);
 137             src += srcStride;
 138          }
 139          span.array->ChanType = CHAN_TYPE;
 140       }
 141       return GL_TRUE;
 142    }
 143
 144    if (format == GL_RGB && type == rbType) {
 145       const GLubyte *src
 146          = (const GLubyte *) _mesa_image_address2d(&unpack, pixels, width,
 147                                                    height, format, type, 0, 0);
 148       const GLint srcStride = _mesa_image_row_stride(&unpack, width,
 149                                                      format, type);
 150       if (simpleZoom) {
 151          GLint row;
 152          for (row = 0; row < drawHeight; row++) {
 153             rb->PutRowRGB(ctx, rb, drawWidth, destX, destY, src, NULL);
 154             src += srcStride;
 155             destY += yStep;
 156          }
 157       }
 158       else {
 159          /* with zooming */
 160          GLint row;
 161          for (row = 0; row < drawHeight; row++) {
 162             span.x = destX;
 163             span.y = destY;
 164             span.end = drawWidth;
 165             span.array->ChanType = rbType;
 166             _swrast_write_zoomed_rgb_span(ctx, imgX, imgY, &span, src);
 167             src += srcStride;
 168             destY++;
 169          }
 170          span.array->ChanType = CHAN_TYPE;
 171       }
 172       return GL_TRUE;
 173    }
 174
 175    /* Remaining cases haven't been tested with alignment != 1 */
 176    if (userUnpack->Alignment != 1)
 177       return GL_FALSE;
 178
 179    if (format == GL_LUMINANCE && type == CHAN_TYPE && rbType == CHAN_TYPE) {
 180       const GLchan *src = (const GLchan *) pixels
 181          + (unpack.SkipRows * unpack.RowLength + unpack.SkipPixels);
 182       if (simpleZoom) {
 183          /* no zooming */
 184          GLint row;
 185          ASSERT(drawWidth <= MAX_WIDTH);
 186          for (row = 0; row < drawHeight; row++) {
 187             GLchan rgb[MAX_WIDTH][3];
 188             GLint i;
 189             for (i = 0;i<drawWidth;i++) {
 190                rgb[i][0] = src[i];
 191                rgb[i][1] = src[i];
 192                rgb[i][2] = src[i];
 193             }
 194             rb->PutRowRGB(ctx, rb, drawWidth, destX, destY, rgb, NULL);
 195             src += unpack.RowLength;
 196             destY += yStep;
 197          }
 198       }
 199       else {
 200          /* with zooming */
 201          GLint row;
 202          ASSERT(drawWidth <= MAX_WIDTH);
 203          for (row = 0; row < drawHeight; row++) {
 204             GLchan rgb[MAX_WIDTH][3];
 205             GLint i;
 206             for (i = 0;i<drawWidth;i++) {
 207                rgb[i][0] = src[i];
 208                rgb[i][1] = src[i];
 209                rgb[i][2] = src[i];
 210             }
 211             span.x = destX;
 212             span.y = destY;
 213             span.end = drawWidth;
 214             _swrast_write_zoomed_rgb_span(ctx, imgX, imgY, &span, rgb);
 215             src += unpack.RowLength;
 216             destY++;
 217          }
 218       }
 219       return GL_TRUE;
 220    }
 221
 222    if (format == GL_LUMINANCE_ALPHA && type == CHAN_TYPE && rbType == CHAN_TYPE) {
 223       const GLchan *src = (const GLchan *) pixels
 224          + (unpack.SkipRows * unpack.RowLength + unpack.SkipPixels)*2;
 225       if (simpleZoom) {
 226          GLint row;
 227          ASSERT(drawWidth <= MAX_WIDTH);
 228          for (row = 0; row < drawHeight; row++) {
 229             GLint i;
 230             const GLchan *ptr = src;
 231             for (i = 0;i<drawWidth;i++) {
 232                span.array->rgba[i][0] = *ptr;
 233                span.array->rgba[i][1] = *ptr;
 234                span.array->rgba[i][2] = *ptr++;
 235                span.array->rgba[i][3] = *ptr++;
 236             }
 237             rb->PutRow(ctx, rb, drawWidth, destX, destY,
 238                        span.array->rgba, NULL);
 239             src += unpack.RowLength*2;
 240             destY += yStep;
 241          }
 242       }
 243       else {
 244          /* with zooming */
 245          GLint row;
 246          ASSERT(drawWidth <= MAX_WIDTH);
 247          for (row = 0; row < drawHeight; row++) {
 248             const GLchan *ptr = src;
 249             GLint i;
 250             for (i = 0;i<drawWidth;i++) {
 251                span.array->rgba[i][0] = *ptr;
 252                span.array->rgba[i][1] = *ptr;
 253                span.array->rgba[i][2] = *ptr++;
 254                span.array->rgba[i][3] = *ptr++;
 255             }
 256             span.x = destX;
 257             span.y = destY;
 258             span.end = drawWidth;
 259             _swrast_write_zoomed_rgba_span(ctx, imgX, imgY, &span,
 260                                            span.array->rgba);
 261             src += unpack.RowLength*2;
 262             destY++;
 263          }
 264       }
 265       return GL_TRUE;
 266    }
 267
 268    if (format == GL_COLOR_INDEX && type == GL_UNSIGNED_BYTE) {
 269       const GLubyte *src = (const GLubyte *) pixels
 270          + unpack.SkipRows * unpack.RowLength + unpack.SkipPixels;
 271       if (rbType == GL_UNSIGNED_BYTE) {
 272          /* convert ubyte/CI data to ubyte/RGBA */
 273          if (simpleZoom) {
 274             GLint row;
 275             for (row = 0; row < drawHeight; row++) {
 276                ASSERT(drawWidth <= MAX_WIDTH);
 277                _mesa_map_ci8_to_rgba8(ctx, drawWidth, src,
 278                                       span.array->rgba8);
 279                rb->PutRow(ctx, rb, drawWidth, destX, destY,
 280                           span.array->rgba8, NULL);
 281                src += unpack.RowLength;
 282                destY += yStep;
 283             }
 284          }
 285          else {
 286             /* ubyte/CI to ubyte/RGBA with zooming */
 287             GLint row;
 288             for (row = 0; row < drawHeight; row++) {
 289                ASSERT(drawWidth <= MAX_WIDTH);
 290                _mesa_map_ci8_to_rgba8(ctx, drawWidth, src,
 291                                       span.array->rgba8);
 292                span.x = destX;
 293                span.y = destY;
 294                span.end = drawWidth;
 295                _swrast_write_zoomed_rgba_span(ctx, imgX, imgY, &span,
 296                                               span.array->rgba8);
 297                src += unpack.RowLength;
 298                destY++;
 299             }
 300          }
 301          return GL_TRUE;
 302       }
 303    }
 304
 305    /* can't handle this pixel format and/or data type */
 306    return GL_FALSE;
 307 }
 308
 309
 310
 311 /*
 312  * Draw stencil image.
 313  */
 314 static void
 315 draw_stencil_pixels( struct gl_context *ctx, GLint x, GLint y,
 316                      GLsizei width, GLsizei height,
 317                      GLenum type,
 318                      const struct gl_pixelstore_attrib *unpack,
 319                      const GLvoid *pixels )
 320 {
 321    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0 || ctx->Pixel.ZoomY != 1.0;
 322    GLint skipPixels;
 323
 324    /* if width > MAX_WIDTH, have to process image in chunks */
 325    skipPixels = 0;
 326    while (skipPixels < width) {
 327       const GLint spanX = x + skipPixels;
 328       const GLint spanWidth = MIN2(width - skipPixels, MAX_WIDTH);
 329       GLint row;
 330       for (row = 0; row < height; row++) {
 331          const GLint spanY = y + row;
 332          GLstencil values[MAX_WIDTH];
 333          GLenum destType = (sizeof(GLstencil) == sizeof(GLubyte))
 334                          ? GL_UNSIGNED_BYTE : GL_UNSIGNED_SHORT;
 335          const GLvoid *source = _mesa_image_address2d(unpack, pixels,
 336                                                       width, height,
 337                                                       GL_COLOR_INDEX, type,
 338                                                       row, skipPixels);
 339          _mesa_unpack_stencil_span(ctx, spanWidth, destType, values,
 340                                    type, source, unpack,
 341                                    ctx->_ImageTransferState);
 342          if (zoom) {
 343             _swrast_write_zoomed_stencil_span(ctx, x, y, spanWidth,
 344                                               spanX, spanY, values);
 345          }
 346          else {
 347             _swrast_write_stencil_span(ctx, spanWidth, spanX, spanY, values);
 348          }
 349       }
 350       skipPixels += spanWidth;
 351    }
 352 }
 353
 354
 355 /*
 356  * Draw depth image.
 357  */
 358 static void
 359 draw_depth_pixels( struct gl_context *ctx, GLint x, GLint y,
 360                    GLsizei width, GLsizei height,
 361                    GLenum type,
 362                    const struct gl_pixelstore_attrib *unpack,
 363                    const GLvoid *pixels )
 364 {
 365    const GLboolean scaleOrBias
 366       = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
 367    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0 || ctx->Pixel.ZoomY != 1.0;
 368    SWspan span;
 369
 370    INIT_SPAN(span, GL_BITMAP);
 371    span.arrayMask = SPAN_Z;
 372    _swrast_span_default_attribs(ctx, &span);
 373
 374    if (type == GL_UNSIGNED_SHORT
 375        && ctx->DrawBuffer->Visual.depthBits == 16
 376        && !scaleOrBias
 377        && !zoom
 378        && width <= MAX_WIDTH
 379        && !unpack->SwapBytes) {
 380       /* Special case: directly write 16-bit depth values */
 381       GLint row;
 382       for (row = 0; row < height; row++) {
 383          const GLushort *zSrc = (const GLushort *)
 384             _mesa_image_address2d(unpack, pixels, width, height,
 385                                   GL_DEPTH_COMPONENT, type, row, 0);
 386          GLint i;
 387          for (i = 0; i < width; i++)
 388             span.array->z[i] = zSrc[i];
 389          span.x = x;
 390          span.y = y + row;
 391          span.end = width;
 392          _swrast_write_rgba_span(ctx, &span);
 393       }
 394    }
 395    else if (type == GL_UNSIGNED_INT
 396             && !scaleOrBias
 397             && !zoom
 398             && width <= MAX_WIDTH
 399             && !unpack->SwapBytes) {
 400       /* Special case: shift 32-bit values down to Visual.depthBits */
 401       const GLint shift = 32 - ctx->DrawBuffer->Visual.depthBits;
 402       GLint row;
 403       for (row = 0; row < height; row++) {
 404          const GLuint *zSrc = (const GLuint *)
 405             _mesa_image_address2d(unpack, pixels, width, height,
 406                                   GL_DEPTH_COMPONENT, type, row, 0);
 407          if (shift == 0) {
 408             memcpy(span.array->z, zSrc, width * sizeof(GLuint));
 409          }
 410          else {
 411             GLint col;
 412             for (col = 0; col < width; col++)
 413                span.array->z[col] = zSrc[col] >> shift;
 414          }
 415          span.x = x;
 416          span.y = y + row;
 417          span.end = width;
 418          _swrast_write_rgba_span(ctx, &span);
 419       }
 420    }
 421    else {
 422       /* General case */
 423       const GLuint depthMax = ctx->DrawBuffer->_DepthMax;
 424       GLint skipPixels = 0;
 425
 426       /* in case width > MAX_WIDTH do the copy in chunks */
 427       while (skipPixels < width) {
 428          const GLint spanWidth = MIN2(width - skipPixels, MAX_WIDTH);
 429          GLint row;
 430          ASSERT(span.end <= MAX_WIDTH);
 431          for (row = 0; row < height; row++) {
 432             const GLvoid *zSrc = _mesa_image_address2d(unpack,
 433                                                       pixels, width, height,
 434                                                       GL_DEPTH_COMPONENT, type,
 435                                                       row, skipPixels);
 436
 437             /* Set these for each row since the _swrast_write_* function may
 438              * change them while clipping.
 439              */
 440             span.x = x + skipPixels;
 441             span.y = y + row;
 442             span.end = spanWidth;
 443
 444             _mesa_unpack_depth_span(ctx, spanWidth,
 445                                     GL_UNSIGNED_INT, span.array->z, depthMax,
 446                                     type, zSrc, unpack);
 447             if (zoom) {
 448                _swrast_write_zoomed_depth_span(ctx, x, y, &span);
 449             }
 450             else {
 451                _swrast_write_rgba_span(ctx, &span);
 452             }
 453          }
 454          skipPixels += spanWidth;
 455       }
 456    }
 457 }
 458
 459
 460
 461 /**
 462  * Draw RGBA image.
 463  */
 464 static void
 465 draw_rgba_pixels( struct gl_context *ctx, GLint x, GLint y,
 466                   GLsizei width, GLsizei height,
 467                   GLenum format, GLenum type,
 468                   const struct gl_pixelstore_attrib *unpack,
 469                   const GLvoid *pixels )
 470 {
 471    const GLint imgX = x, imgY = y;
 472    const GLboolean zoom = ctx->Pixel.ZoomX!=1.0 || ctx->Pixel.ZoomY!=1.0;
 473    GLfloat *convImage = NULL;
 474    GLbitfield transferOps = ctx->_ImageTransferState;
 475    SWspan span;
 476
 477    /* Try an optimized glDrawPixels first */
 478    if (fast_draw_rgba_pixels(ctx, x, y, width, height, format, type,
 479                              unpack, pixels)) {
 480       return;
 481    }
 482
 483    INIT_SPAN(span, GL_BITMAP);
 484    _swrast_span_default_attribs(ctx, &span);
 485    span.arrayMask = SPAN_RGBA;
 486    span.arrayAttribs = FRAG_BIT_COL0; /* we're fill in COL0 attrib values */
 487
 488    if (ctx->DrawBuffer->_NumColorDrawBuffers > 0 &&
 489        ctx->DrawBuffer->_ColorDrawBuffers[0]->DataType != GL_FLOAT &&
 490        ctx->Color.ClampFragmentColor != GL_FALSE) {
 491       /* need to clamp colors before applying fragment ops */
 492       transferOps |= IMAGE_CLAMP_BIT;
 493    }
 494
 495    /*
 496     * General solution
 497     */
 498    {
 499       const GLbitfield interpMask = span.interpMask;
 500       const GLbitfield arrayMask = span.arrayMask;
 501       const GLint srcStride
 502          = _mesa_image_row_stride(unpack, width, format, type);
 503       GLint skipPixels = 0;
 504       /* use span array for temp color storage */
 505       GLfloat *rgba = (GLfloat *) span.array->attribs[FRAG_ATTRIB_COL0];
 506
 507       /* if the span is wider than MAX_WIDTH we have to do it in chunks */
 508       while (skipPixels < width) {
 509          const GLint spanWidth = MIN2(width - skipPixels, MAX_WIDTH);
 510          const GLubyte *source
 511             = (const GLubyte *) _mesa_image_address2d(unpack, pixels,
 512                                                       width, height, format,
 513                                                       type, 0, skipPixels);
 514          GLint row;
 515
 516          for (row = 0; row < height; row++) {
 517             /* get image row as float/RGBA */
 518             _mesa_unpack_color_span_float(ctx, spanWidth, GL_RGBA, rgba,
 519                                      format, type, source, unpack,
 520                                      transferOps);
 521             /* Set these for each row since the _swrast_write_* functions
 522              * may change them while clipping/rendering.
 523              */
 524             span.array->ChanType = GL_FLOAT;
 525             span.x = x + skipPixels;
 526             span.y = y + row;
 527             span.end = spanWidth;
 528             span.arrayMask = arrayMask;
 529             span.interpMask = interpMask;
 530             if (zoom) {
 531                _swrast_write_zoomed_rgba_span(ctx, imgX, imgY, &span, rgba);
 532             }
 533             else {
 534                _swrast_write_rgba_span(ctx, &span);
 535             }
 536
 537             source += srcStride;
 538          } /* for row */
 539
 540          skipPixels += spanWidth;
 541       } /* while skipPixels < width */
 542
 543       /* XXX this is ugly/temporary, to undo above change */
 544       span.array->ChanType = CHAN_TYPE;
 545    }
 546
 547    if (convImage) {
 548       free(convImage);
 549    }
 550 }
 551
 552
 553 /**
 554  * This is a bit different from drawing GL_DEPTH_COMPONENT pixels.
 555  * The only per-pixel operations that apply are depth scale/bias,
 556  * stencil offset/shift, GL_DEPTH_WRITEMASK and GL_STENCIL_WRITEMASK,
 557  * and pixel zoom.
 558  * Also, only the depth buffer and stencil buffers are touched, not the
 559  * color buffer(s).
 560  */
 561 static void
 562 draw_depth_stencil_pixels(struct gl_context *ctx, GLint x, GLint y,
 563                           GLsizei width, GLsizei height, GLenum type,
 564                           const struct gl_pixelstore_attrib *unpack,
 565                           const GLvoid *pixels)
 566 {
 567    const GLint imgX = x, imgY = y;
 568    const GLboolean scaleOrBias
 569       = ctx->Pixel.DepthScale != 1.0 || ctx->Pixel.DepthBias != 0.0;
 570    const GLuint depthMax = ctx->DrawBuffer->_DepthMax;
 571    const GLuint stencilMask = ctx->Stencil.WriteMask[0];
 572    const GLuint stencilType = (STENCIL_BITS == 8) ?
 573       GL_UNSIGNED_BYTE : GL_UNSIGNED_SHORT;
 574    const GLboolean zoom = ctx->Pixel.ZoomX != 1.0 || ctx->Pixel.ZoomY != 1.0;
 575    struct gl_renderbuffer *depthRb, *stencilRb;
 576    struct gl_pixelstore_attrib clippedUnpack = *unpack;
 577
 578    if (!zoom) {
 579       if (!_mesa_clip_drawpixels(ctx, &x, &y, &width, &height,
 580                                  &clippedUnpack)) {
 581          /* totally clipped */
 582          return;
 583       }
 584    }
 585
 586    depthRb = ctx->ReadBuffer->Attachment[BUFFER_DEPTH].Renderbuffer;
 587    stencilRb = ctx->ReadBuffer->Attachment[BUFFER_STENCIL].Renderbuffer;
 588    ASSERT(depthRb);
 589    ASSERT(stencilRb);
 590
 591    if (depthRb->_BaseFormat == GL_DEPTH_STENCIL_EXT &&
 592        stencilRb->_BaseFormat == GL_DEPTH_STENCIL_EXT &&
 593        depthRb == stencilRb &&
 594        !scaleOrBias &&
 595        !zoom &&
 596        ctx->Depth.Mask &&
 597        (stencilMask & 0xff) == 0xff) {
 598       /* This is the ideal case.
 599        * Drawing GL_DEPTH_STENCIL pixels into a combined depth/stencil buffer.
 600        * Plus, no pixel transfer ops, zooming, or masking needed.
 601        */
 602       GLint i;
 603       for (i = 0; i < height; i++) {
 604          const GLuint *src = (const GLuint *)
 605             _mesa_image_address2d(&clippedUnpack, pixels, width, height,
 606                                   GL_DEPTH_STENCIL_EXT, type, i, 0);
 607          depthRb->PutRow(ctx, depthRb, width, x, y + i, src, NULL);
 608       }
 609    }
 610    else {
 611       /* sub-optimal cases:
 612        * Separate depth/stencil buffers, or pixel transfer ops required.
 613        */
 614       /* XXX need to handle very wide images (skippixels) */
 615       GLint i;
 616
 617       depthRb = ctx->DrawBuffer->_DepthBuffer;
 618       stencilRb = ctx->DrawBuffer->_StencilBuffer;
 619
 620       for (i = 0; i < height; i++) {
 621          const GLuint *depthStencilSrc = (const GLuint *)
 622             _mesa_image_address2d(&clippedUnpack, pixels, width, height,
 623                                   GL_DEPTH_STENCIL_EXT, type, i, 0);
 624
 625          if (ctx->Depth.Mask) {
 626             if (!scaleOrBias && ctx->DrawBuffer->Visual.depthBits == 24) {
 627                /* fast path 24-bit zbuffer */
 628                GLuint zValues[MAX_WIDTH];
 629                GLint j;
 630                ASSERT(depthRb->DataType == GL_UNSIGNED_INT);
 631                for (j = 0; j < width; j++) {
 632                   zValues[j] = depthStencilSrc[j] >> 8;
 633                }
 634                if (zoom)
 635                   _swrast_write_zoomed_z_span(ctx, imgX, imgY, width,
 636                                               x, y + i, zValues);
 637                else
 638                   depthRb->PutRow(ctx, depthRb, width, x, y + i, zValues,NULL);
 639             }
 640             else if (!scaleOrBias && ctx->DrawBuffer->Visual.depthBits == 16) {
 641                /* fast path 16-bit zbuffer */
 642                GLushort zValues[MAX_WIDTH];
 643                GLint j;
 644                ASSERT(depthRb->DataType == GL_UNSIGNED_SHORT);
 645                for (j = 0; j < width; j++) {
 646                   zValues[j] = depthStencilSrc[j] >> 16;
 647                }
 648                if (zoom)
 649                   _swrast_write_zoomed_z_span(ctx, imgX, imgY, width,
 650                                               x, y + i, zValues);
 651                else
 652                   depthRb->PutRow(ctx, depthRb, width, x, y + i, zValues,NULL);
 653             }
 654             else {
 655                /* general case */
 656                GLuint zValues[MAX_WIDTH];  /* 16 or 32-bit Z value storage */
 657                _mesa_unpack_depth_span(ctx, width,
 658                                        depthRb->DataType, zValues, depthMax,
 659                                        type, depthStencilSrc, &clippedUnpack);
 660                if (zoom) {
 661                   _swrast_write_zoomed_z_span(ctx, imgX, imgY, width, x,
 662                                               y + i, zValues);
 663                }
 664                else {
 665                   depthRb->PutRow(ctx, depthRb, width, x, y + i, zValues,NULL);
 666                }
 667             }
 668          }
 669
 670          if (stencilMask != 0x0) {
 671             GLstencil stencilValues[MAX_WIDTH];
 672             /* get stencil values, with shift/offset/mapping */
 673             _mesa_unpack_stencil_span(ctx, width, stencilType, stencilValues,
 674                                       type, depthStencilSrc, &clippedUnpack,
 675                                       ctx->_ImageTransferState);
 676             if (zoom)
 677                _swrast_write_zoomed_stencil_span(ctx, imgX, imgY, width,
 678                                                   x, y + i, stencilValues);
 679             else
 680                _swrast_write_stencil_span(ctx, width, x, y + i, stencilValues);
 681          }
 682       }
 683    }
 684 }
 685
 686
 687 /**
 688  * Execute software-based glDrawPixels.
 689  * By time we get here, all error checking will have been done.
 690  */
 691 void
 692 _swrast_DrawPixels( struct gl_context *ctx,
 693                     GLint x, GLint y,
 694                     GLsizei width, GLsizei height,
 695                     GLenum format, GLenum type,
 696                     const struct gl_pixelstore_attrib *unpack,
 697                     const GLvoid *pixels )
 698 {
 699    SWcontext *swrast = SWRAST_CONTEXT(ctx);
 700    GLboolean save_vp_override = ctx->VertexProgram._Overriden;
 701
 702    if (!_mesa_check_conditional_render(ctx))
 703       return; /* don't draw */
 704
 705    /* We are creating fragments directly, without going through vertex
 706     * programs.
 707     *
 708     * This override flag tells the fragment processing code that its input
 709     * comes from a non-standard source, and it may therefore not rely on
 710     * optimizations that assume e.g. constant color if there is no color
 711     * vertex array.
 712     */
 713    _mesa_set_vp_override(ctx, GL_TRUE);
 714
 715    swrast_render_start(ctx);
 716
 717    if (ctx->NewState)
 718       _mesa_update_state(ctx);
 719
 720    if (swrast->NewState)
 721       _swrast_validate_derived( ctx );
 722
 723     pixels = _mesa_map_pbo_source(ctx, unpack, pixels);
 724     if (!pixels) {
 725        swrast_render_finish(ctx);
 726        _mesa_set_vp_override(ctx, save_vp_override);
 727        return;
 728     }
 729
 730    switch (format) {
 731    case GL_STENCIL_INDEX:
 732       draw_stencil_pixels( ctx, x, y, width, height, type, unpack, pixels );
 733       break;
 734    case GL_DEPTH_COMPONENT:
 735       draw_depth_pixels( ctx, x, y, width, height, type, unpack, pixels );
 736       break;
 737    case GL_COLOR_INDEX:
 738    case GL_RED:
 739    case GL_GREEN:
 740    case GL_BLUE:
 741    case GL_ALPHA:
 742    case GL_LUMINANCE:
 743    case GL_LUMINANCE_ALPHA:
 744    case GL_RGB:
 745    case GL_BGR:
 746    case GL_RGBA:
 747    case GL_BGRA:
 748    case GL_ABGR_EXT:
 749       draw_rgba_pixels(ctx, x, y, width, height, format, type, unpack, pixels);
 750       break;
 751    case GL_DEPTH_STENCIL_EXT:
 752       draw_depth_stencil_pixels(ctx, x, y, width, height,
 753                                 type, unpack, pixels);
 754       break;
 755    default:
 756       _mesa_problem(ctx, "unexpected format 0x%x in _swrast_DrawPixels", format);
 757       /* don't return yet, clean-up */
 758    }
 759
 760    swrast_render_finish(ctx);
 761    _mesa_set_vp_override(ctx, save_vp_override);
 762
 763    _mesa_unmap_pbo_source(ctx, unpack);
 764 }