[Mesa-dev] [PATCH] meta: allow nested meta operations

[Xiang, Haihao]

_mesa_meta_CopyPixels results in nested meta operations on Sandybridge.
Previoulsy the second meta operation overrides all states saved by the
first meta function.
---
 src/mesa/drivers/common/meta.c |   14 ++++++++++----
 1 files changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/mesa/drivers/common/meta.c b/src/mesa/drivers/common/meta.c
index 95accc1..32e81c2 100644
--- a/src/mesa/drivers/common/meta.c
+++ b/src/mesa/drivers/common/meta.c
@@ -266,13 +266,14 @@ struct gen_mipmap_state
    GLuint FBO;
 };
 
-
+#define MAX_META_OPS_DEPTH      8
 /**
  * All per-context meta state.
  */
 struct gl_meta_state
 {
-   struct save_state Save;    /**< state saved during meta-ops */
+   struct save_state Save[MAX_META_OPS_DEPTH];    /**< state saved during meta-ops */
+   int current_save_state; 
 
    struct temp_texture TempTex;
 
@@ -324,8 +325,13 @@ _mesa_meta_free(struct gl_context *ctx)
 static void
 _mesa_meta_begin(struct gl_context *ctx, GLbitfield state)
 {
-   struct save_state *save = &ctx->Meta->Save;
+   struct save_state *save;
+
+   /* hope MAX_META_OPS_DEPTH is large enough */
+   assert(current_save_state < MAX_META_OPS_DEPTH);
 
+   save = &ctx->Meta->Save[ctx->Meta->current_save_state++];
+   memset(save, 0, sizeof(*save));
    save->SavedState = state;
 
    if (state & META_ALPHA_TEST) {
@@ -575,7 +581,7 @@ _mesa_meta_begin(struct gl_context *ctx, GLbitfield state)
 static void
 _mesa_meta_end(struct gl_context *ctx)
 {
-   struct save_state *save = &ctx->Meta->Save;
+   struct save_state *save = &ctx->Meta->Save[--ctx->Meta->current_save_state];
    const GLbitfield state = save->SavedState;
 
    if (state & META_ALPHA_TEST) {
-- 
1.7.0.4