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
  41 #include "pipe/p_context.h"
  42 #include "pipe/p_defines.h"
  43 #include "pipe/p_inlines.h"
  44 #include "util/u_tile.h"
  45
  46 #include "st_debug.h"
  47 #include "st_context.h"
  48 #include "st_cb_readpixels.h"
  49 #include "st_cb_fbo.h"
  50 #include "st_public.h"
  51 #include "st_texture.h"
  52 #include "st_inlines.h"
  53
  54 /**
  55  * Special case for reading stencil buffer.
  56  * For color/depth we use get_tile().  For stencil, map the stencil buffer.
  57  */
  58 void
  59 st_read_stencil_pixels(GLcontext *ctx, GLint x, GLint y,
  60                        GLsizei width, GLsizei height,
  61                        GLenum format, GLenum type,
  62                        const struct gl_pixelstore_attrib *packing,
  63                        GLvoid *pixels)
  64 {
  65    struct gl_framebuffer *fb = ctx->ReadBuffer;
  66    struct pipe_screen *screen = ctx->st->pipe->screen;
  67    struct st_renderbuffer *strb = st_renderbuffer(fb->_StencilBuffer);
  68    struct pipe_transfer *pt;
  69    ubyte *stmap;
  70    GLint j;
  71
  72    if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
  73       y = ctx->DrawBuffer->Height - y - height;
  74    }
  75
  76    /* Create a read transfer from the renderbuffer's texture */
  77
  78    pt = st_cond_flush_get_tex_transfer(st_context(ctx), strb->texture,
  79                                        0, 0, 0,
  80                                        PIPE_TRANSFER_READ, x, y,
  81                                        width, height);
  82
  83    /* map the stencil buffer */
  84    stmap = screen->transfer_map(screen, pt);
  85
  86    /* width should never be > MAX_WIDTH since we did clipping earlier */
  87    ASSERT(width <= MAX_WIDTH);
  88
  89    /* process image row by row */
  90    for (j = 0; j < height; j++) {
  91       GLvoid *dest;
  92       GLstencil sValues[MAX_WIDTH];
  93       GLfloat zValues[MAX_WIDTH];
  94       GLint srcY;
  95
  96       if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP) {
  97          srcY = height - j - 1;
  98       }
  99       else {
 100          srcY = j;
 101       }
 102
 103       /* get stencil (and Z) values */
 104       switch (pt->texture->format) {
 105       case PIPE_FORMAT_S8_UNORM:
 106          {
 107             const ubyte *src = stmap + srcY * pt->stride;
 108             memcpy(sValues, src, width);
 109          }
 110          break;
 111       case PIPE_FORMAT_S8Z24_UNORM:
 112          if (format == GL_DEPTH_STENCIL) {
 113             const uint *src = (uint *) (stmap + srcY * pt->stride);
 114             const GLfloat scale = 1.0f / (0xffffff);
 115             GLint k;
 116             for (k = 0; k < width; k++) {
 117                sValues[k] = src[k] >> 24;
 118                zValues[k] = (src[k] & 0xffffff) * scale;
 119             }
 120          }
 121          else {
 122             const uint *src = (uint *) (stmap + srcY * pt->stride);
 123             GLint k;
 124             for (k = 0; k < width; k++) {
 125                sValues[k] = src[k] >> 24;
 126             }
 127          }
 128          break;
 129       case PIPE_FORMAT_Z24S8_UNORM:
 130          if (format == GL_DEPTH_STENCIL) {
 131             const uint *src = (uint *) (stmap + srcY * pt->stride);
 132             const GLfloat scale = 1.0f / (0xffffff);
 133             GLint k;
 134             for (k = 0; k < width; k++) {
 135                sValues[k] = src[k] & 0xff;
 136                zValues[k] = (src[k] >> 8) * scale;
 137             }
 138          }
 139          else {
 140             const uint *src = (uint *) (stmap + srcY * pt->stride);
 141             GLint k;
 142             for (k = 0; k < width; k++) {
 143                sValues[k] = src[k] & 0xff;
 144             }
 145          }
 146          break;
 147       default:
 148          assert(0);
 149       }
 150
 151       /* store */
 152       dest = _mesa_image_address2d(packing, pixels, width, height,
 153                                    format, type, j, 0);
 154       if (format == GL_DEPTH_STENCIL) {
 155          _mesa_pack_depth_stencil_span(ctx, width, dest,
 156                                        zValues, sValues, packing);
 157       }
 158       else {
 159          _mesa_pack_stencil_span(ctx, width, type, dest, sValues, packing);
 160       }
 161    }
 162
 163    /* unmap the stencil buffer */
 164    screen->transfer_unmap(screen, pt);
 165    screen->tex_transfer_destroy(pt);
 166 }
 167
 168
 169 /**
 170  * Return renderbuffer to use for reading color pixels for glRead/CopyPixel
 171  * commands.
 172  * Special care is needed for the front buffer.
 173  */
 174 struct st_renderbuffer *
 175 st_get_color_read_renderbuffer(GLcontext *ctx)
 176 {
 177    struct gl_framebuffer *fb = ctx->ReadBuffer;
 178    struct st_renderbuffer *strb =
 179       st_renderbuffer(fb->_ColorReadBuffer);
 180    struct st_renderbuffer *front =
 181       st_renderbuffer(fb->Attachment[BUFFER_FRONT_LEFT].Renderbuffer);
 182
 183    if (strb == front
 184        && ctx->st->frontbuffer_status == FRONT_STATUS_COPY_OF_BACK) {
 185       /* reading from front color buffer, which is a logical copy of the
 186        * back color buffer.
 187        */
 188       struct st_renderbuffer *back =
 189          st_renderbuffer(fb->Attachment[BUFFER_BACK_LEFT].Renderbuffer);
 190       strb = back;
 191    }
 192
 193    return strb;
 194 }
 195
 196
 197 /**
 198  * Try to do glReadPixels in a fast manner for common cases.
 199  * \return GL_TRUE for success, GL_FALSE for failure
 200  */
 201 static GLboolean
 202 st_fast_readpixels(GLcontext *ctx, struct st_renderbuffer *strb,
 203                    GLint x, GLint y, GLsizei width, GLsizei height,
 204                    GLenum format, GLenum type,
 205                    const struct gl_pixelstore_attrib *pack,
 206                    GLvoid *dest)
 207 {
 208    enum combination {
 209       A8R8G8B8_UNORM_TO_RGBA_UBYTE,
 210       A8R8G8B8_UNORM_TO_RGB_UBYTE,
 211       A8R8G8B8_UNORM_TO_BGRA_UINT
 212    } combo;
 213
 214    if (ctx->_ImageTransferState)
 215       return GL_FALSE;
 216
 217    if (strb->format == PIPE_FORMAT_A8R8G8B8_UNORM &&
 218        format == GL_RGBA && type == GL_UNSIGNED_BYTE) {
 219       combo = A8R8G8B8_UNORM_TO_RGBA_UBYTE;
 220    }
 221    else if (strb->format == PIPE_FORMAT_A8R8G8B8_UNORM &&
 222             format == GL_RGB && type == GL_UNSIGNED_BYTE) {
 223       combo = A8R8G8B8_UNORM_TO_RGB_UBYTE;
 224    }
 225    else if (strb->format == PIPE_FORMAT_A8R8G8B8_UNORM &&
 226             format == GL_BGRA && type == GL_UNSIGNED_INT_8_8_8_8_REV) {
 227       combo = A8R8G8B8_UNORM_TO_BGRA_UINT;
 228    }
 229    else {
 230       return GL_FALSE;
 231    }
 232
 233    /*printf("st_fast_readpixels combo %d\n", (GLint) combo);*/
 234
 235    {
 236       struct pipe_context *pipe = ctx->st->pipe;
 237       struct pipe_screen *screen = pipe->screen;
 238       struct pipe_transfer *trans;
 239       const GLubyte *map;
 240       GLubyte *dst;
 241       GLint row, col, dy, dstStride;
 242
 243       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 244          y = strb->texture->height0 - y - height;
 245       }
 246
 247       trans = st_cond_flush_get_tex_transfer(st_context(ctx), strb->texture,
 248                                              0, 0, 0,
 249                                              PIPE_TRANSFER_READ, x, y,
 250                                              width, height);
 251       if (!trans) {
 252          return GL_FALSE;
 253       }
 254
 255       map = screen->transfer_map(screen, trans);
 256       if (!map) {
 257          screen->tex_transfer_destroy(trans);
 258          return GL_FALSE;
 259       }
 260
 261       if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 262          y = height - 1;
 263          dy = -1;
 264       }
 265       else {
 266          y = 0;
 267          dy = 1;
 268       }
 269
 270       dst = _mesa_image_address2d(pack, dest, width, height,
 271                                   format, type, 0, 0);
 272       dstStride = _mesa_image_row_stride(pack, width, format, type);
 273
 274       switch (combo) {
 275       case A8R8G8B8_UNORM_TO_RGBA_UBYTE:
 276          for (row = 0; row < height; row++) {
 277             const GLubyte *src = map + y * trans->stride;
 278             for (col = 0; col < width; col++) {
 279                GLuint pixel = ((GLuint *) src)[col];
 280                dst[col*4+0] = (pixel >> 16) & 0xff;
 281                dst[col*4+1] = (pixel >>  8) & 0xff;
 282                dst[col*4+2] = (pixel >>  0) & 0xff;
 283                dst[col*4+3] = (pixel >> 24) & 0xff;
 284             }
 285             dst += dstStride;
 286             y += dy;
 287          }
 288          break;
 289       case A8R8G8B8_UNORM_TO_RGB_UBYTE:
 290          for (row = 0; row < height; row++) {
 291             const GLubyte *src = map + y * trans->stride;
 292             for (col = 0; col < width; col++) {
 293                GLuint pixel = ((GLuint *) src)[col];
 294                dst[col*3+0] = (pixel >> 16) & 0xff;
 295                dst[col*3+1] = (pixel >>  8) & 0xff;
 296                dst[col*3+2] = (pixel >>  0) & 0xff;
 297             }
 298             dst += dstStride;
 299             y += dy;
 300          }
 301          break;
 302       case A8R8G8B8_UNORM_TO_BGRA_UINT:
 303          for (row = 0; row < height; row++) {
 304             const GLubyte *src = map + y * trans->stride;
 305             memcpy(dst, src, 4 * width);
 306             dst += dstStride;
 307             y += dy;
 308          }
 309          break;
 310       default:
 311          ; /* nothing */
 312       }
 313
 314       screen->transfer_unmap(screen, trans);
 315       screen->tex_transfer_destroy(trans);
 316    }
 317
 318    return GL_TRUE;
 319 }
 320
 321
 322 /**
 323  * Do glReadPixels by getting rows from the framebuffer transfer with
 324  * get_tile().  Convert to requested format/type with Mesa image routines.
 325  * Image transfer ops are done in software too.
 326  */
 327 static void
 328 st_readpixels(GLcontext *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
 329               GLenum format, GLenum type,
 330               const struct gl_pixelstore_attrib *pack,
 331               GLvoid *dest)
 332 {
 333    struct pipe_context *pipe = ctx->st->pipe;
 334    struct pipe_screen *screen = pipe->screen;
 335    GLfloat temp[MAX_WIDTH][4];
 336    const GLbitfield transferOps = ctx->_ImageTransferState;
 337    GLsizei i, j;
 338    GLint yStep, dfStride;
 339    GLfloat *df;
 340    struct st_renderbuffer *strb;
 341    struct gl_pixelstore_attrib clippedPacking = *pack;
 342    struct pipe_transfer *trans;
 343
 344    assert(ctx->ReadBuffer->Width > 0);
 345
 346    /* XXX convolution not done yet */
 347    assert((transferOps & IMAGE_CONVOLUTION_BIT) == 0);
 348
 349    /* Do all needed clipping here, so that we can forget about it later */
 350    if (!_mesa_clip_readpixels(ctx, &x, &y, &width, &height, &clippedPacking)) {
 351       /* The ReadPixels transfer is totally outside the window bounds */
 352       return;
 353    }
 354
 355    dest = _mesa_map_pbo_dest(ctx, &clippedPacking, dest);
 356    if (!dest)
 357       return;
 358
 359    st_flush(ctx->st, PIPE_FLUSH_RENDER_CACHE, NULL);
 360
 361    if (format == GL_STENCIL_INDEX ||
 362        format == GL_DEPTH_STENCIL) {
 363       st_read_stencil_pixels(ctx, x, y, width, height,
 364                              format, type, pack, dest);
 365       return;
 366    }
 367    else if (format == GL_DEPTH_COMPONENT) {
 368       strb = st_renderbuffer(ctx->ReadBuffer->_DepthBuffer);
 369    }
 370    else {
 371       /* Read color buffer */
 372       strb = st_get_color_read_renderbuffer(ctx);
 373    }
 374
 375    if (!strb)
 376       return;
 377
 378    /* try a fast-path readpixels before anything else */
 379    if (st_fast_readpixels(ctx, strb, x, y, width, height,
 380                           format, type, pack, dest)) {
 381       /* success! */
 382       _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 383       return;
 384    }
 385
 386    if (format == GL_RGBA && type == GL_FLOAT) {
 387       /* write tile(row) directly into user's buffer */
 388       df = (GLfloat *) _mesa_image_address2d(&clippedPacking, dest, width,
 389                                              height, format, type, 0, 0);
 390       dfStride = width * 4;
 391    }
 392    else {
 393       /* write tile(row) into temp row buffer */
 394       df = (GLfloat *) temp;
 395       dfStride = 0;
 396    }
 397
 398    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 399       y = strb->Base.Height - y - height;
 400    }
 401
 402    /* Create a read transfer from the renderbuffer's texture */
 403    trans = st_cond_flush_get_tex_transfer(st_context(ctx), strb->texture,
 404                                           0, 0, 0,
 405                                           PIPE_TRANSFER_READ, x, y,
 406                                           width, height);
 407
 408    /* determine bottom-to-top vs. top-to-bottom order */
 409    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 410       y = height - 1;
 411       yStep = -1;
 412    }
 413    else {
 414       y = 0;
 415       yStep = 1;
 416    }
 417
 418    if (ST_DEBUG & DEBUG_FALLBACK)
 419       debug_printf("%s: fallback processing\n", __FUNCTION__);
 420
 421    /*
 422     * Copy pixels from pipe_transfer to user memory
 423     */
 424    {
 425       /* dest of first pixel in client memory */
 426       GLubyte *dst = _mesa_image_address2d(&clippedPacking, dest, width,
 427                                            height, format, type, 0, 0);
 428       /* dest row stride */
 429       const GLint dstStride = _mesa_image_row_stride(&clippedPacking, width,
 430                                                      format, type);
 431
 432       if (trans->texture->format == PIPE_FORMAT_S8Z24_UNORM ||
 433           trans->texture->format == PIPE_FORMAT_X8Z24_UNORM) {
 434          if (format == GL_DEPTH_COMPONENT) {
 435             for (i = 0; i < height; i++) {
 436                GLuint ztemp[MAX_WIDTH];
 437                GLfloat zfloat[MAX_WIDTH];
 438                const double scale = 1.0 / ((1 << 24) - 1);
 439                pipe_get_tile_raw(trans, 0, y, width, 1, ztemp, 0);
 440                y += yStep;
 441                for (j = 0; j < width; j++) {
 442                   zfloat[j] = (float) (scale * (ztemp[j] & 0xffffff));
 443                }
 444                _mesa_pack_depth_span(ctx, width, dst, type,
 445                                      zfloat, &clippedPacking);
 446                dst += dstStride;
 447             }
 448          }
 449          else {
 450             /* XXX: unreachable code -- should be before st_read_stencil_pixels */
 451             assert(format == GL_DEPTH_STENCIL_EXT);
 452             for (i = 0; i < height; i++) {
 453                GLuint *zshort = (GLuint *)dst;
 454                pipe_get_tile_raw(trans, 0, y, width, 1, dst, 0);
 455                y += yStep;
 456                /* Reverse into 24/8 */
 457                for (j = 0; j < width; j++) {
 458                   zshort[j] = (zshort[j] << 8) | (zshort[j] >> 24);
 459                }
 460                dst += dstStride;
 461             }
 462          }
 463       }
 464       else if (trans->texture->format == PIPE_FORMAT_Z24S8_UNORM ||
 465                trans->texture->format == PIPE_FORMAT_Z24X8_UNORM) {
 466          if (format == GL_DEPTH_COMPONENT) {
 467             for (i = 0; i < height; i++) {
 468                GLuint ztemp[MAX_WIDTH];
 469                GLfloat zfloat[MAX_WIDTH];
 470                const double scale = 1.0 / ((1 << 24) - 1);
 471                pipe_get_tile_raw(trans, 0, y, width, 1, ztemp, 0);
 472                y += yStep;
 473                for (j = 0; j < width; j++) {
 474                   zfloat[j] = (float) (scale * ((ztemp[j] >> 8) & 0xffffff));
 475                }
 476                _mesa_pack_depth_span(ctx, width, dst, type,
 477                                      zfloat, &clippedPacking);
 478                dst += dstStride;
 479             }
 480          }
 481          else {
 482             /* XXX: unreachable code -- should be before st_read_stencil_pixels */
 483             assert(format == GL_DEPTH_STENCIL_EXT);
 484             for (i = 0; i < height; i++) {
 485                pipe_get_tile_raw(trans, 0, y, width, 1, dst, 0);
 486                y += yStep;
 487                dst += dstStride;
 488             }
 489          }
 490       }
 491       else if (trans->texture->format == PIPE_FORMAT_Z16_UNORM) {
 492          for (i = 0; i < height; i++) {
 493             GLushort ztemp[MAX_WIDTH];
 494             GLfloat zfloat[MAX_WIDTH];
 495             const double scale = 1.0 / 0xffff;
 496             pipe_get_tile_raw(trans, 0, y, width, 1, ztemp, 0);
 497             y += yStep;
 498             for (j = 0; j < width; j++) {
 499                zfloat[j] = (float) (scale * ztemp[j]);
 500             }
 501             _mesa_pack_depth_span(ctx, width, dst, type,
 502                                   zfloat, &clippedPacking);
 503             dst += dstStride;
 504          }
 505       }
 506       else if (trans->texture->format == PIPE_FORMAT_Z32_UNORM) {
 507          for (i = 0; i < height; i++) {
 508             GLuint ztemp[MAX_WIDTH];
 509             GLfloat zfloat[MAX_WIDTH];
 510             const double scale = 1.0 / 0xffffffff;
 511             pipe_get_tile_raw(trans, 0, y, width, 1, ztemp, 0);
 512             y += yStep;
 513             for (j = 0; j < width; j++) {
 514                zfloat[j] = (float) (scale * ztemp[j]);
 515             }
 516             _mesa_pack_depth_span(ctx, width, dst, type,
 517                                   zfloat, &clippedPacking);
 518             dst += dstStride;
 519          }
 520       }
 521       else {
 522          /* RGBA format */
 523          /* Do a row at a time to flip image data vertically */
 524          for (i = 0; i < height; i++) {
 525             pipe_get_tile_rgba(trans, 0, y, width, 1, df);
 526             y += yStep;
 527             df += dfStride;
 528             if (!dfStride) {
 529                _mesa_pack_rgba_span_float(ctx, width, temp, format, type, dst,
 530                                           &clippedPacking, transferOps);
 531                dst += dstStride;
 532             }
 533          }
 534       }
 535    }
 536
 537    screen->tex_transfer_destroy(trans);
 538
 539    _mesa_unmap_pbo_dest(ctx, &clippedPacking);
 540 }
 541
 542
 543 void st_init_readpixels_functions(struct dd_function_table *functions)
 544 {
 545    functions->ReadPixels = st_readpixels;
 546 }