[Mesa-dev] [PATCH] mesa: fix tex format selection for GL_R32F and other R/G float formats

[Brian Paul]

The i965 driver advertises GL_ARB_texture_float and GL_ARB_texture_rg
support but the ctx->TextureFormatSupported[] table entries for
MESA_FORMAT_R_FLOAT32 and MESA_FORMAT_RGBA_FLOAT32 are false on gen 4
hardware.  So the case for GL_R32F would fail and we'd print an
implementation error.

This patch adds more Mesa tex format options for GL_R32F and other R/G
formats so we fall back to 16-bit formats when 32-bit formats aren't
available.

Eric made the same fix in commit 6216a5b4 for the non R/G formats.

v2: try 16-bit formats before 32-bit formats and try RG formats before
RGBA where possible.

This should fix https://bugs.freedesktop.org/show_bug.cgi?id=44039

NOTE: This is a candidate for the 8.0 branch.
---
 src/mesa/main/texformat.c |   10 ++++++++++
 1 files changed, 10 insertions(+), 0 deletions(-)

diff --git a/src/mesa/main/texformat.c b/src/mesa/main/texformat.c
index 7e60541..d393873 100644
--- a/src/mesa/main/texformat.c
+++ b/src/mesa/main/texformat.c
@@ -786,21 +786,31 @@ _mesa_choose_tex_format( struct gl_context *ctx, GLint internalFormat,
       switch (internalFormat) {
       case GL_R16F:
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_R_FLOAT16);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT16);
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_R_FLOAT32);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT32);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT16);
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT32);
 	 break;
       case GL_R32F:
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_R_FLOAT32);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT32);
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT32);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_R_FLOAT16);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT16);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT16);
 	 break;
       case GL_RG16F:
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT16);
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT32);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT16);
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT32);
 	 break;
       case GL_RG32F:
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT32);
 	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT32);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RG_FLOAT16);
+	 RETURN_IF_SUPPORTED(MESA_FORMAT_RGBA_FLOAT16);
 	 break;
 
       default:
-- 
1.7.3.4