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    } combo;
 206
 207    if (ctx->_ImageTransferState)
 208       return GL_FALSE;
 209
 210    if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM &&
 211        format == GL_RGBA && type == GL_UNSIGNED_BYTE) {
 212       combo = A8R8G8B8_UNORM_TO_RGBA_UBYTE;
 213    }
 214    else if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM &&
 215             format == GL_RGB && type == GL_UNSIGNED_BYTE) {
 216       combo = A8R8G8B8_UNORM_TO_RGB_UBYTE;
 217    }
 218    else if (strb->format == PIPE_FORMAT_B8G8R8A8_UNORM &&
 219             format == GL_BGRA && type == GL_UNSIGNED_INT_8_8_8_8_REV) {
 220       combo = A8R8G8B8_UNORM_TO_BGRA_UINT;
 221    }
 222    else {
 223       return GL_FALSE;
 224    }
 225
 226    /*printf("st_fast_readpixels combo %d\n", (GLint) combo);*/
 227
 228    {
 229       struct pipe_context *pipe = st_context(ctx)->pipe;
 230       struct pipe_transfer *trans;
 231       const GLubyte *map;
 232       GLubyte *dst;
 233       GLint row, col, dy, dstStride;
 234
 235       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 236          /* convert GL Y to Gallium Y */
 237          y = strb->texture->height0 - y - height;
 238       }
 239
 240       trans = pipe_get_transfer(pipe, strb->texture,
 241                                 0, 0,
 242                                 PIPE_TRANSFER_READ,
 243                                 x, y, width, height);
 244       if (!trans) {
 245          return GL_FALSE;
 246       }
 247
 248       map = pipe_transfer_map(pipe, trans);
 249       if (!map) {
 250          pipe->transfer_destroy(pipe, trans);
 251          return GL_FALSE;
 252       }
 253
 254       /* We always write to the user/dest buffer from low addr to high addr
 255        * but the read order depends on renderbuffer orientation
 256        */
 257       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 258          /* read source rows from bottom to top */
 259          y = height - 1;
 260          dy = -1;
 261       }
 262       else {
 263          /* read source rows from top to bottom */
 264          y = 0;
 265          dy = 1;
 266       }
 267
 268       dst = _mesa_image_address2d(pack, dest, width, height,
 269                                   format, type, 0, 0);
 270       dstStride = _mesa_image_row_stride(pack, width, format, type);
 271
 272       switch (combo) {
 273       case A8R8G8B8_UNORM_TO_RGBA_UBYTE:
 274          for (row = 0; row < height; row++) {
 275             const GLubyte *src = map + y * trans->stride;
 276             for (col = 0; col < width; col++) {
 277                GLuint pixel = ((GLuint *) src)[col];
 278                dst[col*4+0] = (pixel >> 16) & 0xff;
 279                dst[col*4+1] = (pixel >>  8) & 0xff;
 280                dst[col*4+2] = (pixel >>  0) & 0xff;
 281                dst[col*4+3] = (pixel >> 24) & 0xff;
 282             }
 283             dst += dstStride;
 284             y += dy;
 285          }
 286          break;
 287       case A8R8G8B8_UNORM_TO_RGB_UBYTE:
 288          for (row = 0; row < height; row++) {
 289             const GLubyte *src = map + y * trans->stride;
 290             for (col = 0; col < width; col++) {
 291                GLuint pixel = ((GLuint *) src)[col];
 292                dst[col*3+0] = (pixel >> 16) & 0xff;
 293                dst[col*3+1] = (pixel >>  8) & 0xff;
 294                dst[col*3+2] = (pixel >>  0) & 0xff;
 295             }
 296             dst += dstStride;
 297             y += dy;
 298          }
 299          break;
 300       case A8R8G8B8_UNORM_TO_BGRA_UINT:
 301          for (row = 0; row < height; row++) {
 302             const GLubyte *src = map + y * trans->stride;
 303             memcpy(dst, src, 4 * width);
 304             dst += dstStride;
 305             y += dy;
 306          }
 307          break;
 308       default:
 309          ; /* nothing */
 310       }
 311
 312       pipe_transfer_unmap(pipe, trans);
 313       pipe->transfer_destroy(pipe, trans);
 314    }
 315
 316    return GL_TRUE;
 317 }
 318
 319
 320 /**
 321  * Do glReadPixels by getting rows from the framebuffer transfer with
 322  * get_tile().  Convert to requested format/type with Mesa image routines.
 323  * Image transfer ops are done in software too.
 324  */
 325 static void
 326 st_readpixels(struct gl_context *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
 327               GLenum format, GLenum type,
 328               const struct gl_pixelstore_attrib *pack,
 329               GLvoid *dest)
 330 {
 331    struct st_context *st = st_context(ctx);
 332    struct pipe_context *pipe = st->pipe;
 333    GLfloat (*temp)[4];
 334    const GLbitfield transferOps = ctx->_ImageTransferState;
 335    GLsizei i, j;
 336    GLint yStep, dfStride;
 337    GLfloat *df;
 338    struct st_renderbuffer *strb;
 339    struct gl_pixelstore_attrib clippedPacking = *pack;
 340    struct pipe_transfer *trans;
 341    enum pipe_format pformat;
 342
 343    assert(ctx->ReadBuffer->Width > 0);
 344
 345    st_validate_state(st);
 346
 347    /* Do all needed clipping here, so that we can forget about it later */
 348    if (!_mesa_clip_readpixels(ctx, &x, &y, &width, &height, &clippedPacking)) {
 349       /* The ReadPixels transfer is totally outside the window bounds */
 350       return;
 351    }
 352
 353    st_flush_bitmap_cache(st);
 354
 355    dest = _mesa_map_pbo_dest(ctx, &clippedPacking, dest);
 356    if (!dest)
 357       return;
 358
 359    if (format == GL_STENCIL_INDEX ||
 360        format == GL_DEPTH_STENCIL) {
 361       st_read_stencil_pixels(ctx, x, y, width, height,
 362                              format, type, pack, dest);
 363       return;
 364    }
 365    else if (format == GL_DEPTH_COMPONENT) {
 366       strb = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);
 367       if (strb->Base.Wrapped) {
 368          strb = st_renderbuffer(strb->Base.Wrapped);
 369       }
 370    }
 371    else {
 372       /* Read color buffer */
 373       strb = st_get_color_read_renderbuffer(ctx);
 374    }
 375
 376    if (!strb)
 377       return;
 378
 379    /* try a fast-path readpixels before anything else */
 380    if (st_fast_readpixels(ctx, strb, x, y, width, height,
 381                           format, type, pack, dest)) {
 382       /* success! */
 383       _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 384       return;
 385    }
 386
 387    /* allocate temp pixel row buffer */
 388    temp = (GLfloat (*)[4]) malloc(4 * width * sizeof(GLfloat));
 389    if (!temp) {
 390       _mesa_error(ctx, GL_OUT_OF_MEMORY, "glReadPixels");
 391       return;
 392    }
 393
 394    if (format == GL_RGBA && type == GL_FLOAT) {
 395       /* write tile(row) directly into user's buffer */
 396       df = (GLfloat *) _mesa_image_address2d(&clippedPacking, dest, width,
 397                                              height, format, type, 0, 0);
 398       dfStride = width * 4;
 399    }
 400    else {
 401       /* write tile(row) into temp row buffer */
 402       df = (GLfloat *) temp;
 403       dfStride = 0;
 404    }
 405
 406    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 407       /* convert GL Y to Gallium Y */
 408       y = strb->Base.Height - y - height;
 409    }
 410
 411    /* Create a read transfer from the renderbuffer's texture */
 412    trans = pipe_get_transfer(pipe, strb->texture,
 413                              0, 0,
 414                              PIPE_TRANSFER_READ,
 415                              x, y, width, height);
 416
 417    /* determine bottom-to-top vs. top-to-bottom order */
 418    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 419       y = height - 1;
 420       yStep = -1;
 421    }
 422    else {
 423       y = 0;
 424       yStep = 1;
 425    }
 426
 427    /* possibly convert sRGB format to linear RGB format */
 428    pformat = util_format_linear(trans->resource->format);
 429
 430    if (ST_DEBUG & DEBUG_FALLBACK)
 431       debug_printf("%s: fallback processing\n", __FUNCTION__);
 432
 433    /*
 434     * Copy pixels from pipe_transfer to user memory
 435     */
 436    {
 437       /* dest of first pixel in client memory */
 438       GLubyte *dst = _mesa_image_address2d(&clippedPacking, dest, width,
 439                                            height, format, type, 0, 0);
 440       /* dest row stride */
 441       const GLint dstStride = _mesa_image_row_stride(&clippedPacking, width,
 442                                                      format, type);
 443
 444       if (pformat == PIPE_FORMAT_Z24_UNORM_S8_USCALED ||
 445           pformat == PIPE_FORMAT_Z24X8_UNORM) {
 446          if (format == GL_DEPTH_COMPONENT) {
 447             for (i = 0; i < height; i++) {
 448                GLuint ztemp[MAX_WIDTH];
 449                GLfloat zfloat[MAX_WIDTH];
 450                const double scale = 1.0 / ((1 << 24) - 1);
 451                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 452                y += yStep;
 453                for (j = 0; j < width; j++) {
 454                   zfloat[j] = (float) (scale * (ztemp[j] & 0xffffff));
 455                }
 456                _mesa_pack_depth_span(ctx, width, dst, type,
 457                                      zfloat, &clippedPacking);
 458                dst += dstStride;
 459             }
 460          }
 461          else {
 462             /* XXX: unreachable code -- should be before st_read_stencil_pixels */
 463             assert(format == GL_DEPTH_STENCIL_EXT);
 464             for (i = 0; i < height; i++) {
 465                GLuint *zshort = (GLuint *)dst;
 466                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
 467                y += yStep;
 468                /* Reverse into 24/8 */
 469                for (j = 0; j < width; j++) {
 470                   zshort[j] = (zshort[j] << 8) | (zshort[j] >> 24);
 471                }
 472                dst += dstStride;
 473             }
 474          }
 475       }
 476       else if (pformat == PIPE_FORMAT_S8_USCALED_Z24_UNORM ||
 477                pformat == PIPE_FORMAT_X8Z24_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] >> 8) & 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                pipe_get_tile_raw(pipe, trans, 0, y, width, 1, dst, 0);
 498                y += yStep;
 499                dst += dstStride;
 500             }
 501          }
 502       }
 503       else if (pformat == PIPE_FORMAT_Z16_UNORM) {
 504          for (i = 0; i < height; i++) {
 505             GLushort ztemp[MAX_WIDTH];
 506             GLfloat zfloat[MAX_WIDTH];
 507             const double scale = 1.0 / 0xffff;
 508             pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 509             y += yStep;
 510             for (j = 0; j < width; j++) {
 511                zfloat[j] = (float) (scale * ztemp[j]);
 512             }
 513             _mesa_pack_depth_span(ctx, width, dst, type,
 514                                   zfloat, &clippedPacking);
 515             dst += dstStride;
 516          }
 517       }
 518       else if (pformat == PIPE_FORMAT_Z32_UNORM) {
 519          for (i = 0; i < height; i++) {
 520             GLuint ztemp[MAX_WIDTH];
 521             GLfloat zfloat[MAX_WIDTH];
 522             const double scale = 1.0 / 0xffffffff;
 523             pipe_get_tile_raw(pipe, trans, 0, y, width, 1, ztemp, 0);
 524             y += yStep;
 525             for (j = 0; j < width; j++) {
 526                zfloat[j] = (float) (scale * ztemp[j]);
 527             }
 528             _mesa_pack_depth_span(ctx, width, dst, type,
 529                                   zfloat, &clippedPacking);
 530             dst += dstStride;
 531          }
 532       }
 533       else {
 534          /* RGBA format */
 535          /* Do a row at a time to flip image data vertically */
 536          for (i = 0; i < height; i++) {
 537             pipe_get_tile_rgba_format(pipe, trans, 0, y, width, 1,
 538                                       pformat, df);
 539             y += yStep;
 540             df += dfStride;
 541             if (!dfStride) {
 542                _mesa_pack_rgba_span_float(ctx, width, temp, format, type, dst,
 543                                           &clippedPacking, transferOps);
 544                dst += dstStride;
 545             }
 546          }
 547       }
 548    }
 549
 550    free(temp);
 551
 552    pipe->transfer_destroy(pipe, trans);
 553
 554    _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 555 }
 556
 557
 558 void st_init_readpixels_functions(struct dd_function_table *functions)
 559 {
 560    functions->ReadPixels = st_readpixels;
 561 }