Mesa (master): freedreno/a3xx: fix border color swizzle to match texture format desc

[Ilia Mirkin]

Module: Mesa
Branch: master
Commit: fc94b2c2a0600e3e84412d3a01491f2d069119a3
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=fc94b2c2a0600e3e84412d3a01491f2d069119a3

Author: Ilia Mirkin <imirkin at alum.mit.edu>
Date:   Tue Dec  2 23:27:03 2014 -0500

freedreno/a3xx: fix border color swizzle to match texture format desc

This is a hack since it uses the texture information together with the
sampler, but I don't see a better way to do it. In OpenGL, there is a
1:1 correspondence.

Signed-off-by: Ilia Mirkin <imirkin at alum.mit.edu>
Reviewed-by: Rob Clark <robclark at freedesktop.org>

---

 src/gallium/drivers/freedreno/a3xx/fd3_emit.c |   22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/src/gallium/drivers/freedreno/a3xx/fd3_emit.c b/src/gallium/drivers/freedreno/a3xx/fd3_emit.c
index f721303..f9dada7 100644
--- a/src/gallium/drivers/freedreno/a3xx/fd3_emit.c
+++ b/src/gallium/drivers/freedreno/a3xx/fd3_emit.c
@@ -202,10 +202,24 @@ emit_textures(struct fd_context *ctx, struct fd_ringbuffer *ring,
 					(BORDERCOLOR_SIZE * tex_off[sb]) +
 					(BORDERCOLOR_SIZE * i));
 
-			bcolor[0] = util_float_to_half(sampler->base.border_color.f[2]);
-			bcolor[1] = util_float_to_half(sampler->base.border_color.f[1]);
-			bcolor[2] = util_float_to_half(sampler->base.border_color.f[0]);
-			bcolor[3] = util_float_to_half(sampler->base.border_color.f[3]);
+			/*
+			 * XXX HACK ALERT XXX
+			 *
+			 * The border colors need to be swizzled in a particular
+			 * format-dependent order. Even though samplers don't know about
+			 * formats, we can assume that with a GL state tracker, there's a
+			 * 1:1 correspondence between sampler and texture. Take advantage
+			 * of that knowledge.
+			 */
+			if (i < tex->num_textures && tex->textures[i]) {
+				const struct util_format_description *desc =
+					util_format_description(tex->textures[i]->format);
+				for (j = 0; j < 4; j++) {
+					if (desc->swizzle[j] < 4)
+						bcolor[desc->swizzle[j]] =
+							util_float_to_half(sampler->base.border_color.f[j]);
+				}
+			}
 
 			OUT_RING(ring, sampler->texsamp0);
 			OUT_RING(ring, sampler->texsamp1);