src/mesa/state_tracker/st_cb_readpixels.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2007 VMware, Inc.
   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 VMWARE 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 #include "main/bufferobj.h"
  29 #include "main/image.h"
  30 #include "main/pbo.h"
  31 #include "main/imports.h"
  32 #include "main/readpix.h"
  33 #include "main/enums.h"
  34 #include "main/framebuffer.h"
  35 #include "util/u_inlines.h"
  36 #include "util/u_format.h"
  37
  38 #include "st_cb_fbo.h"
  39 #include "st_atom.h"
  40 #include "st_context.h"
  41 #include "st_cb_bitmap.h"
  42 #include "st_cb_readpixels.h"
  43 #include "state_tracker/st_cb_texture.h"
  44 #include "state_tracker/st_format.h"
  45 #include "state_tracker/st_texture.h"
  46
  47 static boolean
  48 needs_integer_signed_unsigned_conversion(const struct gl_context *ctx,
  49                                          GLenum format, GLenum type)
  50 {
  51    struct gl_renderbuffer *rb =
  52       _mesa_get_read_renderbuffer_for_format(ctx, format);
  53
  54    assert(rb);
  55
  56    GLenum srcType = _mesa_get_format_datatype(rb->Format);
  57
  58     if ((srcType == GL_INT &&
  59         (type == GL_UNSIGNED_INT ||
  60          type == GL_UNSIGNED_SHORT ||
  61          type == GL_UNSIGNED_BYTE)) ||
  62        (srcType == GL_UNSIGNED_INT &&
  63         (type == GL_INT ||
  64          type == GL_SHORT ||
  65          type == GL_BYTE))) {
  66       return TRUE;
  67    }
  68
  69    return FALSE;
  70 }
  71
  72 static bool
  73 try_pbo_readpixels(struct st_context *st, struct st_renderbuffer *strb,
  74                    GLint x, GLint y, GLsizei width, GLsizei height,
  75                    enum pipe_format src_format, enum pipe_format dst_format,
  76                    const struct gl_pixelstore_attrib *pack, void *pixels)
  77 {
  78    return false;
  79 }
  80
  81 /**
  82  * This uses a blit to copy the read buffer to a texture format which matches
  83  * the format and type combo and then a fast read-back is done using memcpy.
  84  * We can do arbitrary X/Y/Z/W/0/1 swizzling here as long as there is
  85  * a format which matches the swizzling.
  86  *
  87  * If such a format isn't available, we fall back to _mesa_readpixels.
  88  *
  89  * NOTE: Some drivers use a blit to convert between tiled and linear
  90  *       texture layouts during texture uploads/downloads, so the blit
  91  *       we do here should be free in such cases.
  92  */
  93 static void
  94 st_ReadPixels(struct gl_context *ctx, GLint x, GLint y,
  95               GLsizei width, GLsizei height,
  96               GLenum format, GLenum type,
  97               const struct gl_pixelstore_attrib *pack,
  98               void *pixels)
  99 {
 100    struct st_context *st = st_context(ctx);
 101    struct gl_renderbuffer *rb =
 102          _mesa_get_read_renderbuffer_for_format(ctx, format);
 103    struct st_renderbuffer *strb = st_renderbuffer(rb);
 104    struct pipe_context *pipe = st->pipe;
 105    struct pipe_screen *screen = pipe->screen;
 106    struct pipe_resource *src;
 107    struct pipe_resource *dst = NULL;
 108    struct pipe_resource dst_templ;
 109    enum pipe_format dst_format, src_format;
 110    struct pipe_blit_info blit;
 111    unsigned bind = PIPE_BIND_TRANSFER_READ;
 112    struct pipe_transfer *tex_xfer;
 113    ubyte *map = NULL;
 114
 115    /* Validate state (to be sure we have up-to-date framebuffer surfaces)
 116     * and flush the bitmap cache prior to reading. */
 117    st_validate_state(st, ST_PIPELINE_RENDER);
 118    st_flush_bitmap_cache(st);
 119
 120    if (!st->prefer_blit_based_texture_transfer) {
 121       goto fallback;
 122    }
 123
 124    /* This must be done after state validation. */
 125    src = strb->texture;
 126
 127    /* XXX Fallback for depth-stencil formats due to an incomplete
 128     * stencil blit implementation in some drivers. */
 129    if (format == GL_DEPTH_STENCIL) {
 130       goto fallback;
 131    }
 132
 133    /* If the base internal format and the texture format don't match, we have
 134     * to use the slow path. */
 135    if (rb->_BaseFormat !=
 136        _mesa_get_format_base_format(rb->Format)) {
 137       goto fallback;
 138    }
 139
 140    if (_mesa_readpixels_needs_slow_path(ctx, format, type, GL_TRUE)) {
 141       goto fallback;
 142    }
 143
 144    /* Convert the source format to what is expected by ReadPixels
 145     * and see if it's supported. */
 146    src_format = util_format_linear(src->format);
 147    src_format = util_format_luminance_to_red(src_format);
 148    src_format = util_format_intensity_to_red(src_format);
 149
 150    if (!src_format ||
 151        !screen->is_format_supported(screen, src_format, src->target,
 152                                     src->nr_samples,
 153                                     PIPE_BIND_SAMPLER_VIEW)) {
 154       goto fallback;
 155    }
 156
 157    if (format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL)
 158       bind |= PIPE_BIND_DEPTH_STENCIL;
 159    else
 160       bind |= PIPE_BIND_RENDER_TARGET;
 161
 162    /* Choose the destination format by finding the best match
 163     * for the format+type combo. */
 164    dst_format = st_choose_matching_format(st, bind, format, type,
 165                                           pack->SwapBytes);
 166    if (dst_format == PIPE_FORMAT_NONE) {
 167       goto fallback;
 168    }
 169
 170    if (_mesa_is_bufferobj(pack->BufferObj)) {
 171       if (try_pbo_readpixels(st, strb, x, y, width, height,
 172                              src_format, dst_format,
 173                              pack, pixels))
 174          return;
 175    }
 176
 177    /* We are creating a texture of the size of the region being read back.
 178     * Need to check for NPOT texture support. */
 179    if (!screen->get_param(screen, PIPE_CAP_NPOT_TEXTURES) &&
 180        (!util_is_power_of_two(width) ||
 181         !util_is_power_of_two(height))) {
 182       goto fallback;
 183    }
 184
 185    /* See if the texture format already matches the format and type,
 186     * in which case the memcpy-based fast path will likely be used and
 187     * we don't have to blit. */
 188    if (_mesa_format_matches_format_and_type(rb->Format, format,
 189                                             type, pack->SwapBytes, NULL)) {
 190       goto fallback;
 191    }
 192
 193    if (needs_integer_signed_unsigned_conversion(ctx, format, type)) {
 194       goto fallback;
 195    }
 196
 197    /* create the destination texture */
 198    memset(&dst_templ, 0, sizeof(dst_templ));
 199    dst_templ.target = PIPE_TEXTURE_2D;
 200    dst_templ.format = dst_format;
 201    dst_templ.bind = bind;
 202    dst_templ.usage = PIPE_USAGE_STAGING;
 203
 204    st_gl_texture_dims_to_pipe_dims(GL_TEXTURE_2D, width, height, 1,
 205                                    &dst_templ.width0, &dst_templ.height0,
 206                                    &dst_templ.depth0, &dst_templ.array_size);
 207
 208    dst = screen->resource_create(screen, &dst_templ);
 209    if (!dst) {
 210       goto fallback;
 211    }
 212
 213    memset(&blit, 0, sizeof(blit));
 214    blit.src.resource = src;
 215    blit.src.level = strb->surface->u.tex.level;
 216    blit.src.format = src_format;
 217    blit.dst.resource = dst;
 218    blit.dst.level = 0;
 219    blit.dst.format = dst->format;
 220    blit.src.box.x = x;
 221    blit.dst.box.x = 0;
 222    blit.src.box.y = y;
 223    blit.dst.box.y = 0;
 224    blit.src.box.z = strb->surface->u.tex.first_layer;
 225    blit.dst.box.z = 0;
 226    blit.src.box.width = blit.dst.box.width = width;
 227    blit.src.box.height = blit.dst.box.height = height;
 228    blit.src.box.depth = blit.dst.box.depth = 1;
 229    blit.mask = st_get_blit_mask(rb->_BaseFormat, format);
 230    blit.filter = PIPE_TEX_FILTER_NEAREST;
 231    blit.scissor_enable = FALSE;
 232
 233    if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
 234       blit.src.box.y = rb->Height - blit.src.box.y;
 235       blit.src.box.height = -blit.src.box.height;
 236    }
 237
 238    /* blit */
 239    st->pipe->blit(st->pipe, &blit);
 240
 241    /* map resources */
 242    pixels = _mesa_map_pbo_dest(ctx, pack, pixels);
 243
 244    map = pipe_transfer_map_3d(pipe, dst, 0, PIPE_TRANSFER_READ,
 245                               0, 0, 0, width, height, 1, &tex_xfer);
 246    if (!map) {
 247       _mesa_unmap_pbo_dest(ctx, pack);
 248       pipe_resource_reference(&dst, NULL);
 249       goto fallback;
 250    }
 251
 252    /* memcpy data into a user buffer */
 253    {
 254       const uint bytesPerRow = width * util_format_get_blocksize(dst_format);
 255       GLuint row;
 256
 257       for (row = 0; row < (unsigned) height; row++) {
 258          void *dest = _mesa_image_address2d(pack, pixels,
 259                                               width, height, format,
 260                                               type, row, 0);
 261          memcpy(dest, map, bytesPerRow);
 262          map += tex_xfer->stride;
 263       }
 264    }
 265
 266    pipe_transfer_unmap(pipe, tex_xfer);
 267    _mesa_unmap_pbo_dest(ctx, pack);
 268    pipe_resource_reference(&dst, NULL);
 269    return;
 270
 271 fallback:
 272    _mesa_readpixels(ctx, x, y, width, height, format, type, pack, pixels);
 273 }
 274
 275 void st_init_readpixels_functions(struct dd_function_table *functions)
 276 {
 277    functions->ReadPixels = st_ReadPixels;
 278 }