src/mesa/drivers/dri/intel/intel_pixel_read.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2003 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 #include "main/glheader.h"
  29 #include "main/enums.h"
  30 #include "main/mtypes.h"
  31 #include "main/macros.h"
  32 #include "main/image.h"
  33 #include "main/bufferobj.h"
  34 #include "main/readpix.h"
  35 #include "main/state.h"
  36
  37 #include "intel_screen.h"
  38 #include "intel_context.h"
  39 #include "intel_blit.h"
  40 #include "intel_buffers.h"
  41 #include "intel_regions.h"
  42 #include "intel_pixel.h"
  43 #include "intel_buffer_objects.h"
  44
  45 #define FILE_DEBUG_FLAG DEBUG_PIXEL
  46
  47 /* For many applications, the new ability to pull the source buffers
  48  * back out of the GTT and then do the packing/conversion operations
  49  * in software will be as much of an improvement as trying to get the
  50  * blitter and/or texture engine to do the work.
  51  *
  52  * This step is gated on private backbuffers.
  53  *
  54  * Obviously the frontbuffer can't be pulled back, so that is either
  55  * an argument for blit/texture readpixels, or for blitting to a
  56  * temporary and then pulling that back.
  57  *
  58  * When the destination is a pbo, however, it's not clear if it is
  59  * ever going to be pulled to main memory (though the access param
  60  * will be a good hint).  So it sounds like we do want to be able to
  61  * choose between blit/texture implementation on the gpu and pullback
  62  * and cpu-based copying.
  63  *
  64  * Unless you can magically turn client memory into a PBO for the
  65  * duration of this call, there will be a cpu-based copying step in
  66  * any case.
  67  */
  68
  69 static bool
  70 do_blit_readpixels(struct gl_context * ctx,
  71                    GLint x, GLint y, GLsizei width, GLsizei height,
  72                    GLenum format, GLenum type,
  73                    const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
  74 {
  75    struct intel_context *intel = intel_context(ctx);
  76    struct intel_region *src = intel_readbuf_region(intel);
  77    struct intel_buffer_object *dst = intel_buffer_object(pack->BufferObj);
  78    GLuint dst_offset;
  79    GLuint rowLength;
  80    drm_intel_bo *dst_buffer;
  81    bool all;
  82    GLint dst_x, dst_y;
  83    GLuint dirty;
  84
  85    DBG("%s\n", __FUNCTION__);
  86
  87    if (!src)
  88       return false;
  89
  90    if (!_mesa_is_bufferobj(pack->BufferObj)) {
  91       /* PBO only for now:
  92        */
  93       DBG("%s - not PBO\n", __FUNCTION__);
  94       return false;
  95    }
  96
  97
  98    if (ctx->_ImageTransferState ||
  99        !intel_check_blit_format(src, format, type)) {
 100       DBG("%s - bad format for blit\n", __FUNCTION__);
 101       return false;
 102    }
 103
 104    if (pack->Alignment != 1 || pack->SwapBytes || pack->LsbFirst) {
 105       DBG("%s: bad packing params\n", __FUNCTION__);
 106       return false;
 107    }
 108
 109    if (pack->RowLength > 0)
 110       rowLength = pack->RowLength;
 111    else
 112       rowLength = width;
 113
 114    if (pack->Invert) {
 115       DBG("%s: MESA_PACK_INVERT not done yet\n", __FUNCTION__);
 116       return false;
 117    }
 118    else {
 119       if (ctx->ReadBuffer->Name == 0)
 120          rowLength = -rowLength;
 121    }
 122
 123    dst_offset = (GLintptr)pixels;
 124    dst_offset += _mesa_image_offset(2, pack, width, height,
 125                                     format, type, 0, 0, 0);
 126
 127    if (!_mesa_clip_copytexsubimage(ctx,
 128                                    &dst_x, &dst_y,
 129                                    &x, &y,
 130                                    &width, &height)) {
 131       return true;
 132    }
 133
 134    dirty = intel->front_buffer_dirty;
 135    intel_prepare_render(intel);
 136    intel->front_buffer_dirty = dirty;
 137
 138    all = (width * height * src->cpp == dst->Base.Size &&
 139           x == 0 && dst_offset == 0);
 140
 141    dst_x = 0;
 142    dst_y = 0;
 143
 144    dst_buffer = intel_bufferobj_buffer(intel, dst,
 145                                        all ? INTEL_WRITE_FULL :
 146                                        INTEL_WRITE_PART);
 147
 148    if (ctx->ReadBuffer->Name == 0)
 149       y = ctx->ReadBuffer->Height - (y + height);
 150
 151    if (!intelEmitCopyBlit(intel,
 152                           src->cpp,
 153                           src->pitch, src->bo, 0, src->tiling,
 154                           rowLength, dst_buffer, dst_offset, false,
 155                           x, y,
 156                           dst_x, dst_y,
 157                           width, height,
 158                           GL_COPY)) {
 159       return false;
 160    }
 161
 162    DBG("%s - DONE\n", __FUNCTION__);
 163
 164    return true;
 165 }
 166
 167 void
 168 intelReadPixels(struct gl_context * ctx,
 169                 GLint x, GLint y, GLsizei width, GLsizei height,
 170                 GLenum format, GLenum type,
 171                 const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
 172 {
 173    struct intel_context *intel = intel_context(ctx);
 174    bool dirty;
 175
 176    intel_flush_rendering_to_batch(ctx);
 177
 178    DBG("%s\n", __FUNCTION__);
 179
 180    if (do_blit_readpixels
 181        (ctx, x, y, width, height, format, type, pack, pixels))
 182       return;
 183
 184    /* glReadPixels() wont dirty the front buffer, so reset the dirty
 185     * flag after calling intel_prepare_render(). */
 186    dirty = intel->front_buffer_dirty;
 187    intel_prepare_render(intel);
 188    intel->front_buffer_dirty = dirty;
 189
 190    fallback_debug("%s: fallback to swrast\n", __FUNCTION__);
 191
 192    /* Update Mesa state before calling _mesa_readpixels().
 193     * XXX this may not be needed since ReadPixels no longer uses the
 194     * span code.
 195     */
 196
 197    if (ctx->NewState)
 198       _mesa_update_state(ctx);
 199
 200    _mesa_readpixels(ctx, x, y, width, height, format, type, pack, pixels);
 201
 202    /* There's an intel_prepare_render() call in intelSpanRenderStart(). */
 203    intel->front_buffer_dirty = dirty;
 204 }