diff --git a/src/mesa/state_tracker/st_cb_drawpixels.c b/src/mesa/state_tracker/st_cb_drawpixels.c index d1fe3302c60..51d4ae51918 100644 --- a/src/mesa/state_tracker/st_cb_drawpixels.c +++ b/src/mesa/state_tracker/st_cb_drawpixels.c @@ -72,6 +72,37 @@ #include "cso_cache/cso_context.h" +/** + * We have a simple glDrawPixels cache to try to optimize the case where the + * same image is drawn over and over again. It basically works as follows: + * + * 1. After we construct a texture map with the image and draw it, we do + * not discard the texture. We keep it around, plus we note the + * glDrawPixels width, height, format, etc. parameters and keep a copy + * of the image in a malloc'd buffer. + * + * 2. On the next glDrawPixels we check if the parameters match the previous + * call. If those match, we check if the image matches the previous image + * via a memcmp() call. If everything matches, we re-use the previous + * texture, thereby avoiding the cost creating a new texture and copying + * the image to it. + * + * The effectiveness of this cache depends upon: + * 1. If the memcmp() finds a difference, it happens relatively quickly. + Hopefully, not just the last pixels differ! + * 2. If the memcmp() finds no difference, doing that check is faster than + * creating and loading a texture. + * + * Notes: + * 1. We don't support any pixel unpacking parameters. + * 2. We don't try to cache images in Pixel Buffer Objects. + * 3. Instead of saving the whole image, perhaps some sort of reliable + * checksum function could be used instead. + */ +#define USE_DRAWPIXELS_CACHE 1 + + + /** * Create fragment program that does a TEX() instruction to get a Z and/or * stencil value value, then writes to FRAG_RESULT_DEPTH/FRAG_RESULT_STENCIL. @@ -347,6 +378,39 @@ make_texture(struct st_context *st, enum pipe_format pipeFormat; GLenum baseInternalFormat; +#if USE_DRAWPIXELS_CACHE + const GLint bpp = _mesa_bytes_per_pixel(format, type); + + /* Check if the glDrawPixels() parameters and state matches the cache */ + if (width == st->drawpix_cache.width && + height == st->drawpix_cache.height && + format == st->drawpix_cache.format && + type == st->drawpix_cache.type && + pixels == st->drawpix_cache.user_pointer && + !_mesa_is_bufferobj(unpack->BufferObj) && + (unpack->RowLength == 0 || unpack->RowLength == width) && + unpack->SkipPixels == 0 && + unpack->SkipRows == 0 && + unpack->SwapBytes == GL_FALSE && + st->drawpix_cache.image) { + /* check if the pixel data is the same */ + if (memcmp(pixels, st->drawpix_cache.image, width * height * bpp) == 0) { + /* OK, re-use the cached texture */ + return st->drawpix_cache.texture; + } + } + + /* discard the cached image and texture (if there is one) */ + st->drawpix_cache.width = 0; + st->drawpix_cache.height = 0; + st->drawpix_cache.user_pointer = NULL; + if (st->drawpix_cache.image) { + free(st->drawpix_cache.image); + st->drawpix_cache.image = NULL; + } + pipe_resource_reference(&st->drawpix_cache.texture, NULL); +#endif + /* Choose a pixel format for the temp texture which will hold the * image to draw. */ @@ -437,6 +501,25 @@ make_texture(struct st_context *st, _mesa_unmap_pbo_source(ctx, unpack); +#if USE_DRAWPIXELS_CACHE + /* Save the glDrawPixels parameter and image in the cache */ + if ((unpack->RowLength == 0 || unpack->RowLength == width) && + unpack->SkipPixels == 0 && + unpack->SkipRows == 0) { + st->drawpix_cache.width = width; + st->drawpix_cache.height = height; + st->drawpix_cache.format = format; + st->drawpix_cache.type = type; + st->drawpix_cache.user_pointer = pixels; + assert(!st->drawpix_cache.image); + st->drawpix_cache.image = malloc(width * height * bpp); + if (st->drawpix_cache.image) { + memcpy(st->drawpix_cache.image, pixels, width * height * bpp); + } + st->drawpix_cache.texture = pt; + } +#endif + return pt; } @@ -1067,7 +1150,9 @@ st_DrawPixels(struct gl_context *ctx, GLint x, GLint y, if (num_sampler_view > 1) pipe_sampler_view_reference(&sv[1], NULL); +#if !USE_DRAWPIXELS_CACHE pipe_resource_reference(&pt, NULL); +#endif } diff --git a/src/mesa/state_tracker/st_context.c b/src/mesa/state_tracker/st_context.c index c35055a0a97..e3ddee660f7 100644 --- a/src/mesa/state_tracker/st_context.c +++ b/src/mesa/state_tracker/st_context.c @@ -186,6 +186,10 @@ st_destroy_context_priv(struct st_context *st) u_upload_destroy(st->constbuf_uploader); } + /* free glDrawPixels cache data */ + free(st->drawpix_cache.image); + pipe_resource_reference(&st->drawpix_cache.texture, NULL); + cso_destroy_context(st->cso_context); free( st ); } diff --git a/src/mesa/state_tracker/st_context.h b/src/mesa/state_tracker/st_context.h index 1701c618ebf..f960c64cbe8 100644 --- a/src/mesa/state_tracker/st_context.h +++ b/src/mesa/state_tracker/st_context.h @@ -217,6 +217,14 @@ struct st_context void *vert_shaders[2]; /**< ureg shaders */ } drawpix; + struct { + GLsizei width, height; + GLenum format, type; + const void *user_pointer; /**< Last user 'pixels' pointer */ + void *image; /**< Copy of the glDrawPixels image data */ + struct pipe_resource *texture; + } drawpix_cache; + /** for glClear */ struct { struct pipe_rasterizer_state raster;