diff options
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_wm_surface_state.c | 13 |
1 files changed, 10 insertions, 3 deletions
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 b1f1df11993..b772ef64e48 100644 --- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c +++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c @@ -729,11 +729,18 @@ brw_get_texture_swizzle(const struct gl_texture_object *t) } } - /* For a format with no alpha channel, force the alpha result to - * 1.0. (This allows for an RGBA texture to be used for an RGB - * format, for example). + /* 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 + * implementation to use an RGBA texture for any of these formats + * without leaking any unexpected values. */ switch (img->_BaseFormat) { + case GL_ALPHA: + swizzles[0] = SWIZZLE_ZERO; + swizzles[1] = SWIZZLE_ZERO; + swizzles[2] = SWIZZLE_ZERO; + break; case GL_RED: case GL_RG: case GL_RGB: |