[Mesa-dev] [PATCH] i965: Fix I/L/LA SNORM formats.

[Kenneth Graunke]

_mesa_choose_tex_format (texformat.c) tries I8_SNORM, L8_SNORM, and
either L8A8_SNORM or A8L8_SNORM, none of which are supported by our
driver.  Failing that, it falls back to RGBX for luminance, and RGBA
intensity and luminance alpha.  So, we need to use swizzle overrrides
to obtain the correct values.

Fixes Piglit's EXT_texture_snorm/fbo-blending-formats and
fbo-clear-formats on Gen6-8.

v2: Rebase forward 3 years, don't require texformat.c changes.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/drivers/dri/i965/brw_wm_surface_state.c | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

Tue Jul 17 11:08:59 2012 -0700.

I'm down to 135 branches...making progress...

diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
index ec4dfdb..f479f44 100644
--- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
@@ -187,6 +187,8 @@ brw_get_texture_swizzle(const struct gl_context *ctx,
       }
    }
 
+   GLenum datatype = _mesa_get_format_datatype(img->TexFormat);
+
    /* If the texture's format is alpha-only, force R, G, and B to
     * 0.0. Similarly, if the texture's format has no alpha channel,
     * force the alpha value read to 1.0. This allows for the
@@ -200,13 +202,29 @@ brw_get_texture_swizzle(const struct gl_context *ctx,
       swizzles[2] = SWIZZLE_ZERO;
       break;
    case GL_LUMINANCE:
-      if (t->_IsIntegerFormat) {
+      if (t->_IsIntegerFormat || datatype == GL_SIGNED_NORMALIZED) {
          swizzles[0] = SWIZZLE_X;
          swizzles[1] = SWIZZLE_X;
          swizzles[2] = SWIZZLE_X;
          swizzles[3] = SWIZZLE_ONE;
       }
       break;
+   case GL_LUMINANCE_ALPHA:
+      if (datatype == GL_SIGNED_NORMALIZED) {
+         swizzles[0] = SWIZZLE_X;
+         swizzles[1] = SWIZZLE_X;
+         swizzles[2] = SWIZZLE_X;
+         swizzles[3] = SWIZZLE_W;
+      }
+      break;
+   case GL_INTENSITY:
+      if (datatype == GL_SIGNED_NORMALIZED) {
+         swizzles[0] = SWIZZLE_X;
+         swizzles[1] = SWIZZLE_X;
+         swizzles[2] = SWIZZLE_X;
+         swizzles[3] = SWIZZLE_X;
+      }
+      break;
    case GL_RED:
    case GL_RG:
    case GL_RGB:
-- 
2.2.2