From aa84f1ad5537f5b0232eb681147cb3a3882323b8 Mon Sep 17 00:00:00 2001 From: Roland Scheidegger Date: Wed, 7 Aug 2013 20:33:54 +0200 Subject: [PATCH] softpipe: don't clamp reference value for shadow comparison for float formats Clamping is only done for fixed-point formats as part of conversion to texture format. Reviewed-by: Zack Rusin --- src/gallium/drivers/softpipe/sp_tex_sample.c | 44 ++++++++++++++------ 1 file changed, 32 insertions(+), 12 deletions(-) diff --git a/src/gallium/drivers/softpipe/sp_tex_sample.c b/src/gallium/drivers/softpipe/sp_tex_sample.c index 8de2712ee21..4121857b869 100644 --- a/src/gallium/drivers/softpipe/sp_tex_sample.c +++ b/src/gallium/drivers/softpipe/sp_tex_sample.c @@ -2294,6 +2294,8 @@ sample_compare(struct sp_sampler_view *sp_sview, int j, k0, k1, k2, k3; float val; float pc0, pc1, pc2, pc3; + const struct util_format_description *format_desc; + unsigned chan_type; /** * Compare texcoord 'p' (aka R) against texture value 'rgba[0]' @@ -2304,21 +2306,39 @@ sample_compare(struct sp_sampler_view *sp_sview, if (sp_sview->base.texture->target == PIPE_TEXTURE_2D_ARRAY || sp_sview->base.texture->target == PIPE_TEXTURE_CUBE) { - pc0 = CLAMP(c0[0], 0.0F, 1.0F); - pc1 = CLAMP(c0[1], 0.0F, 1.0F); - pc2 = CLAMP(c0[2], 0.0F, 1.0F); - pc3 = CLAMP(c0[3], 0.0F, 1.0F); + pc0 = c0[0]; + pc1 = c0[1]; + pc2 = c0[2]; + pc3 = c0[3]; } else if (sp_sview->base.texture->target == PIPE_TEXTURE_CUBE_ARRAY) { - pc0 = CLAMP(c1[0], 0.0F, 1.0F); - pc1 = CLAMP(c1[1], 0.0F, 1.0F); - pc2 = CLAMP(c1[2], 0.0F, 1.0F); - pc3 = CLAMP(c1[3], 0.0F, 1.0F); + pc0 = c1[0]; + pc1 = c1[1]; + pc2 = c1[2]; + pc3 = c1[3]; } else { - pc0 = CLAMP(p[0], 0.0F, 1.0F); - pc1 = CLAMP(p[1], 0.0F, 1.0F); - pc2 = CLAMP(p[2], 0.0F, 1.0F); - pc3 = CLAMP(p[3], 0.0F, 1.0F); + pc0 = p[0]; + pc1 = p[1]; + pc2 = p[2]; + pc3 = p[3]; + } + + format_desc = util_format_description(sp_sview->base.format); + /* not entirely sure we couldn't end up with non-valid swizzle here */ + chan_type = format_desc->swizzle[0] <= UTIL_FORMAT_SWIZZLE_W ? + format_desc->channel[format_desc->swizzle[0]].type : + UTIL_FORMAT_TYPE_FLOAT; + if (chan_type != UTIL_FORMAT_TYPE_FLOAT) { + /* + * clamping is a result of conversion to texture format, hence + * doesn't happen with floats. Technically also should do comparison + * in texture format (quantization!). + */ + pc0 = CLAMP(pc0, 0.0F, 1.0F); + pc1 = CLAMP(pc1, 0.0F, 1.0F); + pc2 = CLAMP(pc2, 0.0F, 1.0F); + pc3 = CLAMP(pc3, 0.0F, 1.0F); } + /* compare four texcoords vs. four texture samples */ switch (sampler->compare_func) { case PIPE_FUNC_LESS: -- 2.30.2