src/mesa/state_tracker/st_cb_readpixels.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28
  29 /**
  30  * glReadPixels interface to pipe
  31  *
  32  * \author Brian Paul
  33  */
  34
  35
  36 #include "main/imports.h"
  37 #include "main/bufferobj.h"
  38 #include "main/context.h"
  39 #include "main/image.h"
  40 #include "main/pack.h"
  41 #include "main/pbo.h"
  42
  43 #include "pipe/p_context.h"
  44 #include "pipe/p_defines.h"
  45 #include "util/u_format.h"
  46 #include "util/u_inlines.h"
  47 #include "util/u_tile.h"
  48
  49 #include "st_debug.h"
  50 #include "st_context.h"
  51 #include "st_atom.h"
  52 #include "st_cb_bitmap.h"
  53 #include "st_cb_readpixels.h"
  54 #include "st_cb_fbo.h"
  55
  56 /**
  57  * Special case for reading stencil buffer.
  58  * For color/depth we use get_tile().  For stencil, map the stencil buffer.
  59  */
  60 void
  61 st_read_stencil_pixels(struct gl_context *ctx, GLint x, GLint y,
  62                        GLsizei width, GLsizei height,
  63                        GLenum format, GLenum type,
  64                        const struct gl_pixelstore_attrib *packing,
  65                        GLvoid *pixels)
  66 {
  67    struct gl_framebuffer *fb = ctx->ReadBuffer;
  68    struct pipe_context *pipe = st_context(ctx)->pipe;
  69    struct st_renderbuffer *strb = st_renderbuffer(fb->_StencilBuffer);
  70    struct pipe_transfer *pt;
  71    ubyte *stmap;
  72    GLint j;
  73
  74    if (strb->Base.Wrapped) {
  75       strb = st_renderbuffer(strb->Base.Wrapped);
  76    }
  77
  78    if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
  79       y = ctx->DrawBuffer->Height - y - height;
  80    }
  81
  82    /* Create a read transfer from the renderbuffer's texture */
  83
  84    pt = pipe_get_transfer(pipe, strb->texture,
  85                           0, 0,
  86                           PIPE_TRANSFER_READ,
  87                           x, y, width, height);
  88
  89    /* map the stencil buffer */
  90    stmap = pipe_transfer_map(pipe, pt);
  91
  92    /* width should never be > MAX_WIDTH since we did clipping earlier */
  93    ASSERT(width <= MAX_WIDTH);
  94
  95    /* process image row by row */
  96    for (j = 0; j < height; j++) {
  97       GLvoid *dest;
  98       GLstencil sValues[MAX_WIDTH];
  99       GLfloat zValues[MAX_WIDTH];
 100       GLint srcY;
 101
 102       if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
 103          srcY = height - j - 1;
 104       }
 105       else {
 106          srcY = j;
 107       }
 108
 109       /* get stencil (and Z) values */
 110       switch (pt->resource->format) {
 111       case PIPE_FORMAT_S8_USCALED:
 112          {
 113             const ubyte *src = stmap + srcY * pt->stride;
 114             memcpy(sValues, src, width);
 115          }
 116          break;
 117       case PIPE_FORMAT_Z24_UNORM_S8_USCALED:
 118          if (format == GL_DEPTH_STENCIL) {
 119             const uint *src = (uint *) (stmap + srcY * pt->stride);
 120             const GLfloat scale = 1.0f / (0xffffff);
 121             GLint k;
 122             for (k = 0; k < width; k++) {
 123                sValues[k] = src[k] >> 24;
 124                zValues[k] = (src[k] & 0xffffff) * scale;
 125             }
 126          }
 127          else {
 128             const uint *src = (uint *) (stmap + srcY * pt->stride);
 129             GLint k;
 130             for (k = 0; k < width; k++) {
 131                sValues[k] = src[k] >> 24;
 132             }
 133          }
 134          break;
 135       case PIPE_FORMAT_S8_USCALED_Z24_UNORM:
 136          if (format == GL_DEPTH_STENCIL) {
 137             const uint *src = (uint *) (stmap + srcY * pt->stride);
 138             const GLfloat scale = 1.0f / (0xffffff);
 139             GLint k;
 140             for (k = 0; k < width; k++) {
 141                sValues[k] = src[k] & 0xff;
 142                zValues[k] = (src[k] >> 8) * scale;
 143             }
 144          }
 145          else {
 146             const uint *src = (uint *) (stmap + srcY * pt->stride);
 147             GLint k;
 148             for (k = 0; k < width; k++) {
 149                sValues[k] = src[k] & 0xff;
 150             }
 151          }
 152          break;
 153       default:
 154          assert(0);
 155       }
 156
 157       /* store */
 158       dest = _mesa_image_address2d(packing, pixels, width, height,
 159                                    format, type, j, 0);
 160       if (format == GL_DEPTH_STENCIL) {
 161          _mesa_pack_depth_stencil_span(ctx, width, dest,
 162                                        zValues, sValues, packing);
 163       }
 164       else {
 165          _mesa_pack_stencil_span(ctx, width, type, dest, sValues, packing);
 166       }
 167    }
 168
 169    /* unmap the stencil buffer */
 170    pipe_transfer_unmap(pipe, pt);
 171    pipe->transfer_destroy(pipe, pt);
 172 }
 173
 174
 175 /**
 176  * Return renderbuffer to use for reading color pixels for glRead/CopyPixel
 177  * commands.
 178  */
 179 struct st_renderbuffer *
 180 st_get_color_read_renderbuffer(struct gl_context *ctx)
 181 {
 182    struct gl_framebuffer *fb = ctx->ReadBuffer;
 183    struct st_renderbuffer *strb =
 184       st_renderbuffer(fb->_ColorReadBuffer);
 185
 186    return strb;
 187 }
 188
 189
 190 /**
 191  * Try to do glReadPixels in a fast manner for common cases.
 192  * \return GL_TRUE for success, GL_FALSE for failure
 193  */
 194 static GLboolean
 195 st_fast_readpixels(struct gl_context *ctx, struct st_renderbuffer *strb,
 196                    GLint x, GLint y, GLsizei width, GLsizei height,
 197                    GLenum format, GLenum type,
 198                    const struct gl_pixelstore_attrib *pack,
 199                    GLvoid *dest)
 200 {
 201    GLubyte alphaORoperand;
 202    enum combination {
 203       A8R8G8B8_UNORM_TO_RGBA_UBYTE,
 204       A8R8G8B8_UNORM_TO_RGB_UBYTE,
 205       A8R8G8B8_UNORM_TO_BGRA_UINT,
 206       A8R8G8B8_UNORM_TO_RGBA_UINT
 207    } combo;
 208
 209    if (ctx->_ImageTransferState)
 210       return GL_FALSE;
 211
 212    if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM) {
 213       alphaORoperand = 0;
 214    } else if (strb->format == PIPE_FORMAT_B8G8R8X8_UNORM ) {
 215       alphaORoperand = 0xff;
 216    } else {
 217       return GL_FALSE;
 218    }
 219
 220    if (format == GL_RGBA && type == GL_UNSIGNED_BYTE) {
 221       combo = A8R8G8B8_UNORM_TO_RGBA_UBYTE;
 222    }
 223    else if (format == GL_RGB && type == GL_UNSIGNED_BYTE) {
 224       combo = A8R8G8B8_UNORM_TO_RGB_UBYTE;
 225    }
 226    else if (format == GL_BGRA && type == GL_UNSIGNED_INT_8_8_8_8_REV) {
 227       combo = A8R8G8B8_UNORM_TO_BGRA_UINT;
 228    }
 229    else if (format == GL_RGBA && type == GL_UNSIGNED_INT_8_8_8_8) {
 230       combo = A8R8G8B8_UNORM_TO_RGBA_UINT;
 231    }
 232    else {
 233       return GL_FALSE;
 234    }
 235
 236    /*printf("st_fast_readpixels combo %d\n", (GLint) combo);*/
 237
 238    {
 239       struct pipe_context *pipe = st_context(ctx)->pipe;
 240       struct pipe_transfer *trans;
 241       const GLubyte *map;
 242       GLubyte *dst;
 243       GLint row, col, dy, dstStride;
 244
 245       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 246          /* convert GL Y to Gallium Y */
 247          y = strb->texture->height0 - y - height;
 248       }
 249
 250       trans = pipe_get_transfer(pipe, strb->texture,
 251                                 0, 0,
 252                                 PIPE_TRANSFER_READ,
 253                                 x, y, width, height);
 254       if (!trans) {
 255          return GL_FALSE;
 256       }
 257
 258       map = pipe_transfer_map(pipe, trans);
 259       if (!map) {
 260          pipe->transfer_destroy(pipe, trans);
 261          return GL_FALSE;
 262       }
 263
 264       /* We always write to the user/dest buffer from low addr to high addr
 265        * but the read order depends on renderbuffer orientation
 266        */
 267       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 268          /* read source rows from bottom to top */
 269          y = height - 1;
 270          dy = -1;
 271       }
 272       else {
 273          /* read source rows from top to bottom */
 274          y = 0;
 275          dy = 1;
 276       }
 277
 278       dst = _mesa_image_address2d(pack, dest, width, height,
 279                                   format, type, 0, 0);
 280       dstStride = _mesa_image_row_stride(pack, width, format, type);
 281
 282       switch (combo) {
 283       case A8R8G8B8_UNORM_TO_RGBA_UBYTE:
 284          for (row = 0; row < height; row++) {
 285             const GLubyte *src = map + y * trans->stride;
 286             for (col = 0; col < width; col++) {
 287                GLuint pixel = ((GLuint *) src)[col];
 288                dst[col*4+0] = (pixel >> 16) & 0xff;
 289                dst[col*4+1] = (pixel >>  8) & 0xff;
 290                dst[col*4+2] = (pixel >>  0) & 0xff;
 291                dst[col*4+3] = ((pixel >> 24) & 0xff) | alphaORoperand;
 292             }
 293             dst += dstStride;
 294             y += dy;
 295          }
 296          break;
 297       case A8R8G8B8_UNORM_TO_RGB_UBYTE:
 298          for (row = 0; row < height; row++) {
 299             const GLubyte *src = map + y * trans->stride;
 300             for (col = 0; col < width; col++) {
 301                GLuint pixel = ((GLuint *) src)[col];
 302                dst[col*3+0] = (pixel >> 16) & 0xff;
 303                dst[col*3+1] = (pixel >>  8) & 0xff;
 304                dst[col*3+2] = (pixel >>  0) & 0xff;
 305             }
 306             dst += dstStride;
 307             y += dy;
 308          }
 309          break;
 310       case A8R8G8B8_UNORM_TO_BGRA_UINT:
 311          for (row = 0; row < height; row++) {
 312             const GLubyte *src = map + y * trans->stride;
 313             memcpy(dst, src, 4 * width);
 314             if (alphaORoperand) {
 315                 for (col = 0; col < width; col++) {
 316                     dst[col*4+3] |= alphaORoperand;
 317                 }
 318             }
 319             dst += dstStride;
 320             y += dy;
 321          }
 322          break;
 323       case A8R8G8B8_UNORM_TO_RGBA_UINT:
 324          for (row = 0; row < height; row++) {
 325             const GLubyte *src = map + y * trans->stride;
 326             for (col = 0; col < width; col++) {
 327                GLuint pixel = ((GLuint *) src)[col];
 328                dst[col*4+0] = ((pixel >> 24) & 0xff) | alphaORoperand;
 329                dst[col*4+1] = (pixel >> 0) & 0xff;
 330                dst[col*4+2] = (pixel >> 8) & 0xff;
 331                dst[col*4+3] = (pixel >> 16) & 0xff;
 332             }
 333             dst += dstStride;
 334             y += dy;
 335          }
 336          break;
 337       default:
 338          ; /* nothing */
 339       }
 340
 341       pipe_transfer_unmap(pipe, trans);
 342       pipe->transfer_destroy(pipe, trans);
 343    }
 344
 345    return GL_TRUE;
 346 }
 347
 348
 349 /**
 350  * Do glReadPixels by getting rows from the framebuffer transfer with
 351  * get_tile().  Convert to requested format/type with Mesa image routines.
 352  * Image transfer ops are done in software too.
 353  */
 354 static void
 355 st_readpixels(struct gl_context *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
 356               GLenum format, GLenum type,
 357               const struct gl_pixelstore_attrib *pack,
 358               GLvoid *dest)
 359 {
 360    struct st_context *st = st_context(ctx);
 361    struct pipe_context *pipe = st->pipe;
 362    GLfloat (*temp)[4];
 363    GLbitfield transferOps = ctx->_ImageTransferState;
 364    GLsizei i, j;
 365    GLint yStep, dfStride;
 366    GLfloat *df;
 367    struct st_renderbuffer *strb;
 368    struct gl_pixelstore_attrib clippedPacking = *pack;
 369    struct pipe_transfer *trans;
 370    enum pipe_format pformat;
 371
 372    assert(ctx->ReadBuffer->Width > 0);
 373
 374    st_validate_state(st);
 375
 376    /* Do all needed clipping here, so that we can forget about it later */
 377    if (!_mesa_clip_readpixels(ctx, &x, &y, &width, &height, &clippedPacking)) {
 378       /* The ReadPixels transfer is totally outside the window bounds */
 379       return;
 380    }
 381
 382    st_flush_bitmap_cache(st);
 383
 384    dest = _mesa_map_pbo_dest(ctx, &clippedPacking, dest);
 385    if (!dest)
 386       return;
 387
 388    if (format == GL_STENCIL_INDEX ||
 389        format == GL_DEPTH_STENCIL) {
 390       st_read_stencil_pixels(ctx, x, y, width, height,
 391                              format, type, pack, dest);
 392       return;
 393    }
 394    else if (format == GL_DEPTH_COMPONENT) {
 395       strb = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);
 396       if (strb->Base.Wrapped) {
 397          strb = st_renderbuffer(strb->Base.Wrapped);
 398       }
 399    }
 400    else {
 401       /* Read color buffer */
 402       strb = st_get_color_read_renderbuffer(ctx);
 403    }
 404
 405    if (!strb)
 406       return;
 407
 408    /* try a fast-path readpixels before anything else */
 409    if (st_fast_readpixels(ctx, strb, x, y, width, height,
 410                           format, type, pack, dest)) {
 411       /* success! */
 412       _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 413       return;
 414    }
 415
 416    /* allocate temp pixel row buffer */
 417    temp = (GLfloat (*)[4]) malloc(4 * width * sizeof(GLfloat));
 418    if (!temp) {
 419       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
 420       return;
 421    }
 422
 423    if(ctx->Color._ClampReadColor)
 424       transferOps |= IMAGE_CLAMP_BIT;
 425
 426    if (format == GL_RGBA && type == GL_FLOAT && !transferOps) {
 427       /* write tile(row) directly into user's buffer */
 428       df = (GLfloat *) _mesa_image_address2d(&clippedPacking, dest, width,
 429                                              height, format, type, 0, 0);
 430       dfStride = width * 4;
 431    }
 432    else {
 433       /* write tile(row) into temp row buffer */
 434       df = (GLfloat *) temp;
 435       dfStride = 0;
 436    }
 437
 438    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 439       /* convert GL Y to Gallium Y */
 440       y = strb->Base.Height - y - height;
 441    }
 442
 443    /* Create a read transfer from the renderbuffer's texture */
 444    trans = pipe_get_transfer(pipe, strb->texture,
 445                              0, 0,
 446                              PIPE_TRANSFER_READ,
 447                              x, y, width, height);
 448
 449    /* determine bottom-to-top vs. top-to-bottom order */
 450    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 451       y = height - 1;
 452       yStep = -1;
 453    }
 454    else {
 455       y = 0;
 456       yStep = 1;
 457    }
 458
 459    /* possibly convert sRGB format to linear RGB format */
 460    pformat = util_format_linear(trans->resource->format);
 461
 462    if (ST_DEBUG & DEBUG_FALLBACK)
 463       debug_printf("%s: fallback processing\n", __FUNCTION__);
 464
 465    /*
 466     * Copy pixels from pipe_transfer to user memory
 467     */
 468    {
 469       /* dest of first pixel in client memory */
 470       GLubyte *dst = _mesa_image_address2d(&clippedPacking, dest, width,
 471                                            height, format, type, 0, 0);
 472       /* dest row stride */
 473       const GLint dstStride = _mesa_image_row_stride(&clippedPacking, width,
 474                                                      format, type);
 475
 476       if (pformat == PIPE_FORMAT_Z24_UNORM_S8_USCALED ||
 477           pformat == PIPE_FORMAT_Z24X8_UNORM) {
 478          if (format == GL_DEPTH_COMPONENT) {
 479             for (i = 0; i < height; i++) {
 480                GLuint ztemp[MAX_WIDTH];
 481                GLfloat zfloat[MAX_WIDTH];
 482                const double scale = 1.0 / ((1 << 24) - 1);
 483                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 484                y += yStep;
 485                for (j = 0; j < width; j++) {
 486                   zfloat[j] = (float) (scale * (ztemp[j] & 0xffffff));
 487                }
 488                _mesa_pack_depth_span(ctx, width, dst, type,
 489                                      zfloat, &clippedPacking);
 490                dst += dstStride;
 491             }
 492          }
 493          else {
 494             /* XXX: unreachable code -- should be before st_read_stencil_pixels */
 495             assert(format == GL_DEPTH_STENCIL_EXT);
 496             for (i = 0; i < height; i++) {
 497                GLuint *zshort = (GLuint *)dst;
 498                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
 499                y += yStep;
 500                /* Reverse into 24/8 */
 501                for (j = 0; j < width; j++) {
 502                   zshort[j] = (zshort[j] << 8) | (zshort[j] >> 24);
 503                }
 504                dst += dstStride;
 505             }
 506          }
 507       }
 508       else if (pformat == PIPE_FORMAT_S8_USCALED_Z24_UNORM ||
 509                pformat == PIPE_FORMAT_X8Z24_UNORM) {
 510          if (format == GL_DEPTH_COMPONENT) {
 511             for (i = 0; i < height; i++) {
 512                GLuint ztemp[MAX_WIDTH];
 513                GLfloat zfloat[MAX_WIDTH];
 514                const double scale = 1.0 / ((1 << 24) - 1);
 515                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 516                y += yStep;
 517                for (j = 0; j < width; j++) {
 518                   zfloat[j] = (float) (scale * ((ztemp[j] >> 8) & 0xffffff));
 519                }
 520                _mesa_pack_depth_span(ctx, width, dst, type,
 521                                      zfloat, &clippedPacking);
 522                dst += dstStride;
 523             }
 524          }
 525          else {
 526             /* XXX: unreachable code -- should be before st_read_stencil_pixels */
 527             assert(format == GL_DEPTH_STENCIL_EXT);
 528             for (i = 0; i < height; i++) {
 529                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
 530                y += yStep;
 531                dst += dstStride;
 532             }
 533          }
 534       }
 535       else if (pformat == PIPE_FORMAT_Z16_UNORM) {
 536          for (i = 0; i < height; i++) {
 537             GLushort ztemp[MAX_WIDTH];
 538             GLfloat zfloat[MAX_WIDTH];
 539             const double scale = 1.0 / 0xffff;
 540             pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 541             y += yStep;
 542             for (j = 0; j < width; j++) {
 543                zfloat[j] = (float) (scale * ztemp[j]);
 544             }
 545             _mesa_pack_depth_span(ctx, width, dst, type,
 546                                   zfloat, &clippedPacking);
 547             dst += dstStride;
 548          }
 549       }
 550       else if (pformat == PIPE_FORMAT_Z32_UNORM) {
 551          for (i = 0; i < height; i++) {
 552             GLuint ztemp[MAX_WIDTH];
 553             GLfloat zfloat[MAX_WIDTH];
 554             const double scale = 1.0 / 0xffffffff;
 555             pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 556             y += yStep;
 557             for (j = 0; j < width; j++) {
 558                zfloat[j] = (float) (scale * ztemp[j]);
 559             }
 560             _mesa_pack_depth_span(ctx, width, dst, type,
 561                                   zfloat, &clippedPacking);
 562             dst += dstStride;
 563          }
 564       }
 565       else {
 566          /* RGBA format */
 567          /* Do a row at a time to flip image data vertically */
 568          for (i = 0; i < height; i++) {
 569             pipe_get_tile_rgba_format(pipe, trans, 0, y, width, 1,
 570                                       pformat, df);
 571             y += yStep;
 572             df += dfStride;
 573             if (!dfStride) {
 574                _mesa_pack_rgba_span_float(ctx, width, temp, format, type, dst,
 575                                           &clippedPacking, transferOps);
 576                dst += dstStride;
 577             }
 578          }
 579       }
 580    }
 581
 582    free(temp);
 583
 584    pipe->transfer_destroy(pipe, trans);
 585
 586    _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 587 }
 588
 589
 590 void st_init_readpixels_functions(struct dd_function_table *functions)
 591 {
 592    functions->ReadPixels = st_readpixels;
 593 }