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path: root/mesalib/src/mesa/state_tracker/st_cb_readpixels.c
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Diffstat (limited to 'mesalib/src/mesa/state_tracker/st_cb_readpixels.c')
-rw-r--r--mesalib/src/mesa/state_tracker/st_cb_readpixels.c188
1 files changed, 181 insertions, 7 deletions
diff --git a/mesalib/src/mesa/state_tracker/st_cb_readpixels.c b/mesalib/src/mesa/state_tracker/st_cb_readpixels.c
index 6b824b161..bfed98870 100644
--- a/mesalib/src/mesa/state_tracker/st_cb_readpixels.c
+++ b/mesalib/src/mesa/state_tracker/st_cb_readpixels.c
@@ -25,35 +25,209 @@
*
**************************************************************************/
-
+#include "main/image.h"
+#include "main/pbo.h"
#include "main/imports.h"
#include "main/readpix.h"
+#include "main/enums.h"
+#include "main/framebuffer.h"
+#include "util/u_inlines.h"
+#include "util/u_format.h"
+#include "st_cb_fbo.h"
#include "st_atom.h"
#include "st_context.h"
#include "st_cb_bitmap.h"
#include "st_cb_readpixels.h"
+#include "state_tracker/st_cb_texture.h"
+#include "state_tracker/st_format.h"
+#include "state_tracker/st_texture.h"
/**
- * The only special thing we need to do for the state tracker's
- * glReadPixels is to validate state (to be sure we have up-to-date
- * framebuffer surfaces) and flush the bitmap cache prior to reading.
+ * This uses a blit to copy the read buffer to a texture format which matches
+ * the format and type combo and then a fast read-back is done using memcpy.
+ * We can do arbitrary X/Y/Z/W/0/1 swizzling here as long as there is
+ * a format which matches the swizzling.
+ *
+ * If such a format isn't available, we fall back to _mesa_readpixels.
+ *
+ * NOTE: Some drivers use a blit to convert between tiled and linear
+ * texture layouts during texture uploads/downloads, so the blit
+ * we do here should be free in such cases.
*/
static void
st_readpixels(struct gl_context *ctx, GLint x, GLint y,
GLsizei width, GLsizei height,
GLenum format, GLenum type,
const struct gl_pixelstore_attrib *pack,
- GLvoid *dest)
+ GLvoid *pixels)
{
struct st_context *st = st_context(ctx);
+ struct gl_renderbuffer *rb =
+ _mesa_get_read_renderbuffer_for_format(ctx, format);
+ struct st_renderbuffer *strb = st_renderbuffer(rb);
+ struct pipe_context *pipe = st->pipe;
+ struct pipe_screen *screen = pipe->screen;
+ struct pipe_resource *src;
+ struct pipe_resource *dst = NULL;
+ struct pipe_resource dst_templ;
+ enum pipe_format dst_format, src_format;
+ struct pipe_blit_info blit;
+ unsigned bind = PIPE_BIND_TRANSFER_READ;
+ struct pipe_transfer *tex_xfer;
+ ubyte *map = NULL;
+ /* Validate state (to be sure we have up-to-date framebuffer surfaces)
+ * and flush the bitmap cache prior to reading. */
st_validate_state(st);
st_flush_bitmap_cache(st);
- _mesa_readpixels(ctx, x, y, width, height, format, type, pack, dest);
-}
+ if (!st->prefer_blit_based_texture_transfer) {
+ goto fallback;
+ }
+
+ /* This must be done after state validation. */
+ src = strb->texture;
+
+ /* XXX Fallback for depth-stencil formats due to an incomplete
+ * stencil blit implementation in some drivers. */
+ if (format == GL_DEPTH_STENCIL) {
+ goto fallback;
+ }
+
+ /* We are creating a texture of the size of the region being read back.
+ * Need to check for NPOT texture support. */
+ if (!screen->get_param(screen, PIPE_CAP_NPOT_TEXTURES) &&
+ (!util_is_power_of_two(width) ||
+ !util_is_power_of_two(height))) {
+ goto fallback;
+ }
+
+ /* If the base internal format and the texture format don't match, we have
+ * to use the slow path. */
+ if (rb->_BaseFormat !=
+ _mesa_get_format_base_format(rb->Format)) {
+ goto fallback;
+ }
+
+ /* See if the texture format already matches the format and type,
+ * in which case the memcpy-based fast path will likely be used and
+ * we don't have to blit. */
+ if (_mesa_format_matches_format_and_type(rb->Format, format,
+ type, pack->SwapBytes)) {
+ goto fallback;
+ }
+
+ if (_mesa_readpixels_needs_slow_path(ctx, format, type, GL_TRUE)) {
+ goto fallback;
+ }
+
+ /* Convert the source format to what is expected by ReadPixels
+ * and see if it's supported. */
+ src_format = util_format_linear(src->format);
+ src_format = util_format_luminance_to_red(src_format);
+ src_format = util_format_intensity_to_red(src_format);
+
+ if (!src_format ||
+ !screen->is_format_supported(screen, src_format, src->target,
+ src->nr_samples,
+ PIPE_BIND_SAMPLER_VIEW)) {
+ printf("fallback: src format unsupported %s\n", util_format_short_name(src_format));
+ goto fallback;
+ }
+
+ if (format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL)
+ bind |= PIPE_BIND_DEPTH_STENCIL;
+ else
+ bind |= PIPE_BIND_RENDER_TARGET;
+
+ /* Choose the destination format by finding the best match
+ * for the format+type combo. */
+ dst_format = st_choose_matching_format(screen, bind, format, type,
+ pack->SwapBytes);
+ if (dst_format == PIPE_FORMAT_NONE) {
+ printf("fallback: no matching format for %s, %s\n",
+ _mesa_lookup_enum_by_nr(format), _mesa_lookup_enum_by_nr(type));
+ goto fallback;
+ }
+
+ /* create the destination texture */
+ memset(&dst_templ, 0, sizeof(dst_templ));
+ dst_templ.target = PIPE_TEXTURE_2D;
+ dst_templ.format = dst_format;
+ dst_templ.bind = bind;
+ dst_templ.usage = PIPE_USAGE_STAGING;
+
+ st_gl_texture_dims_to_pipe_dims(GL_TEXTURE_2D, width, height, 1,
+ &dst_templ.width0, &dst_templ.height0,
+ &dst_templ.depth0, &dst_templ.array_size);
+
+ dst = screen->resource_create(screen, &dst_templ);
+ if (!dst) {
+ goto fallback;
+ }
+
+ blit.src.resource = src;
+ blit.src.level = strb->rtt_level;
+ blit.src.format = src_format;
+ blit.dst.resource = dst;
+ blit.dst.level = 0;
+ blit.dst.format = dst->format;
+ blit.src.box.x = x;
+ blit.dst.box.x = 0;
+ blit.src.box.y = y;
+ blit.dst.box.y = 0;
+ blit.src.box.z = strb->rtt_face + strb->rtt_slice;
+ blit.dst.box.z = 0;
+ blit.src.box.width = blit.dst.box.width = width;
+ blit.src.box.height = blit.dst.box.height = height;
+ blit.src.box.depth = blit.dst.box.depth = 1;
+ blit.mask = st_get_blit_mask(rb->_BaseFormat, format);
+ blit.filter = PIPE_TEX_FILTER_NEAREST;
+ blit.scissor_enable = FALSE;
+
+ if (st_fb_orientation(ctx->ReadBuffer) == Y_0_TOP) {
+ blit.src.box.y = rb->Height - blit.src.box.y;
+ blit.src.box.height = -blit.src.box.height;
+ }
+
+ /* blit */
+ st->pipe->blit(st->pipe, &blit);
+
+ /* map resources */
+ pixels = _mesa_map_pbo_dest(ctx, pack, pixels);
+
+ map = pipe_transfer_map_3d(pipe, dst, 0, PIPE_TRANSFER_READ,
+ 0, 0, 0, width, height, 1, &tex_xfer);
+ if (!map) {
+ _mesa_unmap_pbo_dest(ctx, pack);
+ pipe_resource_reference(&dst, NULL);
+ goto fallback;
+ }
+
+ /* memcpy data into a user buffer */
+ {
+ const uint bytesPerRow = width * util_format_get_blocksize(dst_format);
+ GLuint row;
+
+ for (row = 0; row < height; row++) {
+ GLvoid *dest = _mesa_image_address3d(pack, pixels,
+ width, height, format,
+ type, 0, row, 0);
+ memcpy(dest, map, bytesPerRow);
+ map += tex_xfer->stride;
+ }
+ }
+
+ pipe_transfer_unmap(pipe, tex_xfer);
+ _mesa_unmap_pbo_dest(ctx, pack);
+ pipe_resource_reference(&dst, NULL);
+ return;
+
+fallback:
+ _mesa_readpixels(ctx, x, y, width, height, format, type, pack, pixels);
+}
void st_init_readpixels_functions(struct dd_function_table *functions)
{