void
intelReadPixels(struct gl_context * ctx,
GLint x, GLint y, GLsizei width, GLsizei height,
GLenum format, GLenum type,
const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
{
bool ok;
struct brw_context *brw = brw_context(ctx);
bool dirty;
DBG("%s\n", __func__);
/* Reading pixels wont dirty the front buffer, so reset the dirty
* flag after calling intel_prepare_render().
*/
dirty = brw->front_buffer_dirty;
intel_prepare_render(brw);
brw->front_buffer_dirty = dirty;
if (_mesa_is_bufferobj(pack->BufferObj)) {
if (intel_readpixels_blorp(ctx, x, y, width, height,
format, type, pixels, pack))
return;
perf_debug("%s: fallback to CPU mapping in PBO case\n", __func__);
}
ok = intel_readpixels_tiled_memcpy(ctx, x, y, width, height,
format, type, pixels, pack);
if(ok)
return;
/* Update Mesa state before calling _mesa_readpixels().
* XXX this may not be needed since ReadPixels no longer uses the
* span code.
*/
if (ctx->NewState)
_mesa_update_state(ctx);
_mesa_readpixels(ctx, x, y, width, height, format, type, pack, pixels);
/* There's an intel_prepare_render() call in intelSpanRenderStart(). */
brw->front_buffer_dirty = dirty;
}
void
intelReadPixels(struct gl_context * ctx,
GLint x, GLint y, GLsizei width, GLsizei height,
GLenum format, GLenum type,
const struct gl_pixelstore_attrib *pack, GLvoid * pixels)
{
bool ok;
struct brw_context *brw = brw_context(ctx);
bool dirty;
DBG("%s\n", __func__);
if (_mesa_is_bufferobj(pack->BufferObj)) {
if (_mesa_meta_pbo_GetTexSubImage(ctx, 2, NULL, x, y, 0, width, height, 1,
format, type, pixels, pack)) {
/* _mesa_meta_pbo_GetTexSubImage() implements PBO transfers by
* binding the user-provided BO as a fake framebuffer and rendering
* to it. This breaks the invariant of the GL that nothing is able
* to render to a BO, causing nondeterministic corruption issues
* because the render cache is not coherent with a number of other
* caches that the BO could potentially be bound to afterwards.
*
* This could be solved in the same way that we guarantee texture
* coherency after a texture is attached to a framebuffer and
* rendered to, but that would involve checking *all* BOs bound to
* the pipeline for the case we need to emit a cache flush due to
* previous rendering to any of them -- Including vertex, index,
* uniform, atomic counter, shader image, transform feedback,
* indirect draw buffers, etc.
*
* That would increase the per-draw call overhead even though it's
* very unlikely that any of the BOs bound to the pipeline has been
* rendered to via a PBO at any point, so it seems better to just
* flush here unconditionally.
*/
brw_emit_mi_flush(brw);
return;
}
perf_debug("%s: fallback to CPU mapping in PBO case\n", __func__);
}
ok = intel_readpixels_tiled_memcpy(ctx, x, y, width, height,
format, type, pixels, pack);
if(ok)
return;
/* glReadPixels() wont dirty the front buffer, so reset the dirty
* flag after calling intel_prepare_render(). */
dirty = brw->front_buffer_dirty;
intel_prepare_render(brw);
brw->front_buffer_dirty = dirty;
/* Update Mesa state before calling _mesa_readpixels().
* XXX this may not be needed since ReadPixels no longer uses the
* span code.
*/
if (ctx->NewState)
_mesa_update_state(ctx);
_mesa_readpixels(ctx, x, y, width, height, format, type, pack, pixels);
/* There's an intel_prepare_render() call in intelSpanRenderStart(). */
brw->front_buffer_dirty = dirty;
}
