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    enum combination {
 202       A8R8G8B8_UNORM_TO_RGBA_UBYTE,
 203       A8R8G8B8_UNORM_TO_RGB_UBYTE,
 204       A8R8G8B8_UNORM_TO_BGRA_UINT,
 205       A8R8G8B8_UNORM_TO_RGBA_UINT
 206    } combo;
 207
 208    if (ctx->_ImageTransferState)
 209       return GL_FALSE;
 210
 211    if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM &&
 212        format == GL_RGBA && type == GL_UNSIGNED_BYTE) {
 213       combo = A8R8G8B8_UNORM_TO_RGBA_UBYTE;
 214    }
 215    else if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM &&
 216             format == GL_RGB && type == GL_UNSIGNED_BYTE) {
 217       combo = A8R8G8B8_UNORM_TO_RGB_UBYTE;
 218    }
 219    else if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM &&
 220             format == GL_BGRA && type == GL_UNSIGNED_INT_8_8_8_8_REV) {
 221       combo = A8R8G8B8_UNORM_TO_BGRA_UINT;
 222    }
 223    else if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM &&
 224             format == GL_RGBA && type == GL_UNSIGNED_INT_8_8_8_8) {
 225       combo = A8R8G8B8_UNORM_TO_RGBA_UINT;
 226    }
 227    else {
 228       return GL_FALSE;
 229    }
 230
 231    /*printf("st_fast_readpixels combo %d\n", (GLint) combo);*/
 232
 233    {
 234       struct pipe_context *pipe = st_context(ctx)->pipe;
 235       struct pipe_transfer *trans;
 236       const GLubyte *map;
 237       GLubyte *dst;
 238       GLint row, col, dy, dstStride;
 239
 240       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 241          /* convert GL Y to Gallium Y */
 242          y = strb->texture->height0 - y - height;
 243       }
 244
 245       trans = pipe_get_transfer(pipe, strb->texture,
 246                                 0, 0,
 247                                 PIPE_TRANSFER_READ,
 248                                 x, y, width, height);
 249       if (!trans) {
 250          return GL_FALSE;
 251       }
 252
 253       map = pipe_transfer_map(pipe, trans);
 254       if (!map) {
 255          pipe->transfer_destroy(pipe, trans);
 256          return GL_FALSE;
 257       }
 258
 259       /* We always write to the user/dest buffer from low addr to high addr
 260        * but the read order depends on renderbuffer orientation
 261        */
 262       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 263          /* read source rows from bottom to top */
 264          y = height - 1;
 265          dy = -1;
 266       }
 267       else {
 268          /* read source rows from top to bottom */
 269          y = 0;
 270          dy = 1;
 271       }
 272
 273       dst = _mesa_image_address2d(pack, dest, width, height,
 274                                   format, type, 0, 0);
 275       dstStride = _mesa_image_row_stride(pack, width, format, type);
 276
 277       switch (combo) {
 278       case A8R8G8B8_UNORM_TO_RGBA_UBYTE:
 279          for (row = 0; row < height; row++) {
 280             const GLubyte *src = map + y * trans->stride;
 281             for (col = 0; col < width; col++) {
 282                GLuint pixel = ((GLuint *) src)[col];
 283                dst[col*4+0] = (pixel >> 16) & 0xff;
 284                dst[col*4+1] = (pixel >>  8) & 0xff;
 285                dst[col*4+2] = (pixel >>  0) & 0xff;
 286                dst[col*4+3] = (pixel >> 24) & 0xff;
 287             }
 288             dst += dstStride;
 289             y += dy;
 290          }
 291          break;
 292       case A8R8G8B8_UNORM_TO_RGB_UBYTE:
 293          for (row = 0; row < height; row++) {
 294             const GLubyte *src = map + y * trans->stride;
 295             for (col = 0; col < width; col++) {
 296                GLuint pixel = ((GLuint *) src)[col];
 297                dst[col*3+0] = (pixel >> 16) & 0xff;
 298                dst[col*3+1] = (pixel >>  8) & 0xff;
 299                dst[col*3+2] = (pixel >>  0) & 0xff;
 300             }
 301             dst += dstStride;
 302             y += dy;
 303          }
 304          break;
 305       case A8R8G8B8_UNORM_TO_BGRA_UINT:
 306          for (row = 0; row < height; row++) {
 307             const GLubyte *src = map + y * trans->stride;
 308             memcpy(dst, src, 4 * width);
 309             dst += dstStride;
 310             y += dy;
 311          }
 312          break;
 313       case A8R8G8B8_UNORM_TO_RGBA_UINT:
 314          for (row = 0; row < height; row++) {
 315             const GLubyte *src = map + y * trans->stride;
 316             for (col = 0; col < width; col++) {
 317                GLuint pixel = ((GLuint *) src)[col];
 318                dst[col*4+0] = (pixel >> 24) & 0xff;
 319                dst[col*4+1] = (pixel >> 0) & 0xff;
 320                dst[col*4+2] = (pixel >> 8) & 0xff;
 321                dst[col*4+3] = (pixel >> 16) & 0xff;
 322             }
 323             dst += dstStride;
 324             y += dy;
 325          }
 326          break;
 327       default:
 328          ; /* nothing */
 329       }
 330
 331       pipe_transfer_unmap(pipe, trans);
 332       pipe->transfer_destroy(pipe, trans);
 333    }
 334
 335    return GL_TRUE;
 336 }
 337
 338
 339 /**
 340  * Do glReadPixels by getting rows from the framebuffer transfer with
 341  * get_tile().  Convert to requested format/type with Mesa image routines.
 342  * Image transfer ops are done in software too.
 343  */
 344 static void
 345 st_readpixels(struct gl_context *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
 346               GLenum format, GLenum type,
 347               const struct gl_pixelstore_attrib *pack,
 348               GLvoid *dest)
 349 {
 350    struct st_context *st = st_context(ctx);
 351    struct pipe_context *pipe = st->pipe;
 352    GLfloat (*temp)[4];
 353    GLbitfield transferOps = ctx->_ImageTransferState;
 354    GLsizei i, j;
 355    GLint yStep, dfStride;
 356    GLfloat *df;
 357    struct st_renderbuffer *strb;
 358    struct gl_pixelstore_attrib clippedPacking = *pack;
 359    struct pipe_transfer *trans;
 360    enum pipe_format pformat;
 361
 362    assert(ctx->ReadBuffer->Width > 0);
 363
 364    st_validate_state(st);
 365
 366    /* Do all needed clipping here, so that we can forget about it later */
 367    if (!_mesa_clip_readpixels(ctx, &x, &y, &width, &height, &clippedPacking)) {
 368       /* The ReadPixels transfer is totally outside the window bounds */
 369       return;
 370    }
 371
 372    st_flush_bitmap_cache(st);
 373
 374    dest = _mesa_map_pbo_dest(ctx, &clippedPacking, dest);
 375    if (!dest)
 376       return;
 377
 378    if (format == GL_STENCIL_INDEX ||
 379        format == GL_DEPTH_STENCIL) {
 380       st_read_stencil_pixels(ctx, x, y, width, height,
 381                              format, type, pack, dest);
 382       return;
 383    }
 384    else if (format == GL_DEPTH_COMPONENT) {
 385       strb = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);
 386       if (strb->Base.Wrapped) {
 387          strb = st_renderbuffer(strb->Base.Wrapped);
 388       }
 389    }
 390    else {
 391       /* Read color buffer */
 392       strb = st_get_color_read_renderbuffer(ctx);
 393    }
 394
 395    if (!strb)
 396       return;
 397
 398    /* try a fast-path readpixels before anything else */
 399    if (st_fast_readpixels(ctx, strb, x, y, width, height,
 400                           format, type, pack, dest)) {
 401       /* success! */
 402       _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 403       return;
 404    }
 405
 406    /* allocate temp pixel row buffer */
 407    temp = (GLfloat (*)[4]) malloc(4 * width * sizeof(GLfloat));
 408    if (!temp) {
 409       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
 410       return;
 411    }
 412
 413    if(ctx->Color._ClampReadColor)
 414       transferOps |= IMAGE_CLAMP_BIT;
 415
 416    if (format == GL_RGBA && type == GL_FLOAT && !transferOps) {
 417       /* write tile(row) directly into user's buffer */
 418       df = (GLfloat *) _mesa_image_address2d(&clippedPacking, dest, width,
 419                                              height, format, type, 0, 0);
 420       dfStride = width * 4;
 421    }
 422    else {
 423       /* write tile(row) into temp row buffer */
 424       df = (GLfloat *) temp;
 425       dfStride = 0;
 426    }
 427
 428    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 429       /* convert GL Y to Gallium Y */
 430       y = strb->Base.Height - y - height;
 431    }
 432
 433    /* Create a read transfer from the renderbuffer's texture */
 434    trans = pipe_get_transfer(pipe, strb->texture,
 435                              0, 0,
 436                              PIPE_TRANSFER_READ,
 437                              x, y, width, height);
 438
 439    /* determine bottom-to-top vs. top-to-bottom order */
 440    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 441       y = height - 1;
 442       yStep = -1;
 443    }
 444    else {
 445       y = 0;
 446       yStep = 1;
 447    }
 448
 449    /* possibly convert sRGB format to linear RGB format */
 450    pformat = util_format_linear(trans->resource->format);
 451
 452    if (ST_DEBUG & DEBUG_FALLBACK)
 453       debug_printf("%s: fallback processing\n", __FUNCTION__);
 454
 455    /*
 456     * Copy pixels from pipe_transfer to user memory
 457     */
 458    {
 459       /* dest of first pixel in client memory */
 460       GLubyte *dst = _mesa_image_address2d(&clippedPacking, dest, width,
 461                                            height, format, type, 0, 0);
 462       /* dest row stride */
 463       const GLint dstStride = _mesa_image_row_stride(&clippedPacking, width,
 464                                                      format, type);
 465
 466       if (pformat == PIPE_FORMAT_Z24_UNORM_S8_USCALED ||
 467           pformat == PIPE_FORMAT_Z24X8_UNORM) {
 468          if (format == GL_DEPTH_COMPONENT) {
 469             for (i = 0; i < height; i++) {
 470                GLuint ztemp[MAX_WIDTH];
 471                GLfloat zfloat[MAX_WIDTH];
 472                const double scale = 1.0 / ((1 << 24) - 1);
 473                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 474                y += yStep;
 475                for (j = 0; j < width; j++) {
 476                   zfloat[j] = (float) (scale * (ztemp[j] & 0xffffff));
 477                }
 478                _mesa_pack_depth_span(ctx, width, dst, type,
 479                                      zfloat, &clippedPacking);
 480                dst += dstStride;
 481             }
 482          }
 483          else {
 484             /* XXX: unreachable code -- should be before st_read_stencil_pixels */
 485             assert(format == GL_DEPTH_STENCIL_EXT);
 486             for (i = 0; i < height; i++) {
 487                GLuint *zshort = (GLuint *)dst;
 488                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
 489                y += yStep;
 490                /* Reverse into 24/8 */
 491                for (j = 0; j < width; j++) {
 492                   zshort[j] = (zshort[j] << 8) | (zshort[j] >> 24);
 493                }
 494                dst += dstStride;
 495             }
 496          }
 497       }
 498       else if (pformat == PIPE_FORMAT_S8_USCALED_Z24_UNORM ||
 499                pformat == PIPE_FORMAT_X8Z24_UNORM) {
 500          if (format == GL_DEPTH_COMPONENT) {
 501             for (i = 0; i < height; i++) {
 502                GLuint ztemp[MAX_WIDTH];
 503                GLfloat zfloat[MAX_WIDTH];
 504                const double scale = 1.0 / ((1 << 24) - 1);
 505                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 506                y += yStep;
 507                for (j = 0; j < width; j++) {
 508                   zfloat[j] = (float) (scale * ((ztemp[j] >> 8) & 0xffffff));
 509                }
 510                _mesa_pack_depth_span(ctx, width, dst, type,
 511                                      zfloat, &clippedPacking);
 512                dst += dstStride;
 513             }
 514          }
 515          else {
 516             /* XXX: unreachable code -- should be before st_read_stencil_pixels */
 517             assert(format == GL_DEPTH_STENCIL_EXT);
 518             for (i = 0; i < height; i++) {
 519                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
 520                y += yStep;
 521                dst += dstStride;
 522             }
 523          }
 524       }
 525       else if (pformat == PIPE_FORMAT_Z16_UNORM) {
 526          for (i = 0; i < height; i++) {
 527             GLushort ztemp[MAX_WIDTH];
 528             GLfloat zfloat[MAX_WIDTH];
 529             const double scale = 1.0 / 0xffff;
 530             pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 531             y += yStep;
 532             for (j = 0; j < width; j++) {
 533                zfloat[j] = (float) (scale * ztemp[j]);
 534             }
 535             _mesa_pack_depth_span(ctx, width, dst, type,
 536                                   zfloat, &clippedPacking);
 537             dst += dstStride;
 538          }
 539       }
 540       else if (pformat == PIPE_FORMAT_Z32_UNORM) {
 541          for (i = 0; i < height; i++) {
 542             GLuint ztemp[MAX_WIDTH];
 543             GLfloat zfloat[MAX_WIDTH];
 544             const double scale = 1.0 / 0xffffffff;
 545             pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 546             y += yStep;
 547             for (j = 0; j < width; j++) {
 548                zfloat[j] = (float) (scale * ztemp[j]);
 549             }
 550             _mesa_pack_depth_span(ctx, width, dst, type,
 551                                   zfloat, &clippedPacking);
 552             dst += dstStride;
 553          }
 554       }
 555       else {
 556          /* RGBA format */
 557          /* Do a row at a time to flip image data vertically */
 558          for (i = 0; i < height; i++) {
 559             pipe_get_tile_rgba_format(pipe, trans, 0, y, width, 1,
 560                                       pformat, df);
 561             y += yStep;
 562             df += dfStride;
 563             if (!dfStride) {
 564                _mesa_pack_rgba_span_float(ctx, width, temp, format, type, dst,
 565                                           &clippedPacking, transferOps);
 566                dst += dstStride;
 567             }
 568          }
 569       }
 570    }
 571
 572    free(temp);
 573
 574    pipe->transfer_destroy(pipe, trans);
 575
 576    _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 577 }
 578
 579
 580 void st_init_readpixels_functions(struct dd_function_table *functions)
 581 {
 582    functions->ReadPixels = st_readpixels;
 583 }