From 6f2936c654c68388b9c43a189a1b8c06f3a9d241 Mon Sep 17 00:00:00 2001 From: Marek Olšák Date: Sun, 25 Jul 2010 23:40:51 +0200 Subject: r300g: implement D24X8 texture sampling for r3xx-r4xx Because the hw can't sample it, I reinterpret the format as G16R16 and sample the G component. This gives 16 bits of precision, which should be enough for depth texturing (surprisingly, the sampled values are exactly the same as in D16 textures). This also enables EXT_packed_depth_stencil on those old chipsets, finally. --- src/gallium/drivers/r300/r300_state_derived.c | 33 +++++++++++++++++---------- 1 file changed, 21 insertions(+), 12 deletions(-) (limited to 'src/gallium/drivers/r300/r300_state_derived.c') diff --git a/src/gallium/drivers/r300/r300_state_derived.c b/src/gallium/drivers/r300/r300_state_derived.c index 48912e1555..a85db27064 100644 --- a/src/gallium/drivers/r300/r300_state_derived.c +++ b/src/gallium/drivers/r300/r300_state_derived.c @@ -528,15 +528,9 @@ static void r300_merge_textures_and_samplers(struct r300_context* r300) struct r300_sampler_state *sampler; struct r300_sampler_view *view; struct r300_texture *tex; - unsigned min_level, max_level, i, size; + unsigned min_level, max_level, i, j, size; unsigned count = MIN2(state->sampler_view_count, state->sampler_state_count); - unsigned char depth_swizzle[4] = { - UTIL_FORMAT_SWIZZLE_X, - UTIL_FORMAT_SWIZZLE_X, - UTIL_FORMAT_SWIZZLE_X, - UTIL_FORMAT_SWIZZLE_X - }; /* The KIL opcode fix, see below. */ if (!count && !r300->screen->caps.is_r500) @@ -563,14 +557,29 @@ static void r300_merge_textures_and_samplers(struct r300_context* r300) /* Assign a texture cache region. */ texstate->format.format1 |= view->texcache_region; - /* If compare mode is disabled, the sampler view swizzles - * are stored in the format. - * Otherwise, swizzles must be applied after the compare mode - * in the fragment shader. */ + /* Depth textures are kinda special. */ if (util_format_is_depth_or_stencil(tex->desc.b.b.format)) { + unsigned char depth_swizzle[4]; + + if (!r300->screen->caps.is_r500 && + util_format_get_blocksizebits(tex->desc.b.b.format) == 32) { + /* X24x8 is sampled as Y16X16 on r3xx-r4xx. + * The depth here is at the Y component. */ + for (j = 0; j < 4; j++) + depth_swizzle[j] = UTIL_FORMAT_SWIZZLE_Y; + } else { + for (j = 0; j < 4; j++) + depth_swizzle[j] = UTIL_FORMAT_SWIZZLE_X; + } + + /* If compare mode is disabled, sampler view swizzles + * are stored in the format. + * Otherwise, the swizzles must be applied after the compare + * mode in the fragment shader. */ if (sampler->state.compare_mode == PIPE_TEX_COMPARE_NONE) { texstate->format.format1 |= - r300_get_swizzle_combined(depth_swizzle, view->swizzle); + r300_get_swizzle_combined(depth_swizzle, + view->swizzle); } else { texstate->format.format1 |= r300_get_swizzle_combined(depth_swizzle, 0); -- cgit v1.2.3