[Mesa-dev] [PATCH 2/3] meta: Unset the textures_used_by_txf bitfield.

[Kenneth Graunke]

Drivers that use Meta are happily using blitting data using texelFetch
and GL_SKIP_DECODE_EXT, but the GL_EXT_texture_sRGB spec unfortunately
makes GL_SKIP_DECODE_EXT not necessarily work with texelFetch.

As a hack, just unset the texture_used_by_txf bitfield so we can
continue with the old desired behavior.
---
 src/mesa/drivers/common/meta.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/src/mesa/drivers/common/meta.c b/src/mesa/drivers/common/meta.c
index 73143842485..658a62885bd 100644
--- a/src/mesa/drivers/common/meta.c
+++ b/src/mesa/drivers/common/meta.c
@@ -87,6 +87,7 @@
 #include "main/glformats.h"
 #include "util/bitscan.h"
 #include "util/ralloc.h"
+#include "compiler/nir/nir.h"
 
 /** Return offset in bytes of the field within a vertex struct */
 #define OFFSET(FIELD) ((void *) offsetof(struct vertex, FIELD))
@@ -195,6 +196,17 @@ _mesa_meta_compile_and_link_program(struct gl_context *ctx,
 
    _mesa_meta_link_program_with_debug(ctx, sh_prog);
 
+   struct gl_program *fp =
+      sh_prog->_LinkedShaders[MESA_SHADER_FRAGMENT]->Program;
+
+   /* texelFetch() can break GL_SKIP_DECODE_EXT, but many meta passes want
+    * to use both together; pretend that we're not using texelFetch to hack
+    * around this bad interaction.
+    */
+   fp->info.textures_used_by_txf = 0;
+   if (fp->nir)
+      fp->nir->info.textures_used_by_txf = 0;
+
    _mesa_meta_use_program(ctx, sh_prog);
 
    *out_sh_prog = sh_prog;
-- 
2.14.2