llvmpipe: Add a new scene state to describe scenes which only have state changes.

It's a rare condition, but it may happen if all primitives are
clipped/culled.

For now we just do a no-op rasterization, but we could bypass it.

1 files changed, 4 insertions, 3 deletions

diff --git a/src/gallium/drivers/llvmpipe/lp_setup_context.h b/src/gallium/drivers/llvmpipe/lp_setup_context.h
index c8b8a2480b..8f4e00f073 100644
--- a/src/gallium/drivers/llvmpipe/lp_setup_context.h
+++ b/src/gallium/drivers/llvmpipe/lp_setup_context.h
@@ -101,9 +101,10 @@ struct lp_setup_context
    } clear;
 
    enum setup_state {
-      SETUP_FLUSHED,
-      SETUP_CLEARED,
-      SETUP_ACTIVE
+      SETUP_FLUSHED,    /**< scene is null */
+      SETUP_EMPTY,      /**< scene exists but has only state changes */
+      SETUP_CLEARED,    /**< scene exists but has only clears */
+      SETUP_ACTIVE      /**< scene exists and has at least one draw/query */
    } state;
    
    struct {