svga: add comment about unsupported blend modes

diff --git a/src/gallium/drivers/svga/svga_pipe_blend.c b/src/gallium/drivers/svga/svga_pipe_blend.c
index a9f1c4fa0c8490dd86c003358597d7a191d56336..408e175fea7509f915fa6b3f802cec808c6f33fa 100644 (file)
--- a/src/gallium/drivers/svga/svga_pipe_blend.c
+++ b/src/gallium/drivers/svga/svga_pipe_blend.c
@@ -37,6 +37,9 @@
 static inline unsigned
 svga_translate_blend_factor(const struct svga_context *svga, unsigned factor)
 {
+   /* Note: there is no SVGA3D_BLENDOP_[INV]BLENDFACTORALPHA so
+    * we can't translate PIPE_BLENDFACTOR_[INV_]CONST_ALPHA properly.
+    */
    switch (factor) {
    case PIPE_BLENDFACTOR_ZERO:            return SVGA3D_BLENDOP_ZERO;
    case PIPE_BLENDFACTOR_SRC_ALPHA:       return SVGA3D_BLENDOP_SRCALPHA;