[Mesa-dev] [PATCH 2/7] vbo: Add a predraw resolve callback

[Chris Wilson]

A common problem with using HiZ and multisampling is that surfaces need
to resolved prior to use. Currently i965 does this inside its state
update hook, but that is a comparatively heavyweight operation that need
not be performed so frequently. The obvious solution (and therefore
fraught with dragons) is to move the HiZ/color resolves into the
brw_draw_prims() - however, the resolves are performed using meta and
end up re-entering brw_draw_prims() corrupting the context state of the
original call. To avoid the meta recursion, we can add a new callback
(vbo->resolve()) into the vbo pipeline that is called just before
vbo->draw().

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Brian Paul <brianp at vmware.com>
Cc: Jordan Justen <jordan.l.justen at intel.com>
Cc: Jason Ekstrand <jason.ekstrand at intel.com>
Cc: Kenneth Graunke <kenneth at whitecape.org>
Cc: Francisco Jerez <currojerez at riseup.net>
---
 src/mesa/vbo/vbo.h            |  1 +
 src/mesa/vbo/vbo_context.c    | 19 +++++++++++++++++++
 src/mesa/vbo/vbo_context.h    |  1 +
 src/mesa/vbo/vbo_exec_array.c |  1 +
 src/mesa/vbo/vbo_exec_draw.c  |  5 ++++-
 src/mesa/vbo/vbo_save_draw.c  |  2 ++
 6 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/src/mesa/vbo/vbo.h b/src/mesa/vbo/vbo.h
index 2aaff5d..b64c468 100644
--- a/src/mesa/vbo/vbo.h
+++ b/src/mesa/vbo/vbo.h
@@ -89,6 +89,7 @@ vbo_initialize_save_dispatch(const struct gl_context *ctx,
                              struct _glapi_table *exec);
 
 
+typedef void (*vbo_resolve_func)( struct gl_context *ctx);
 typedef void (*vbo_draw_func)( struct gl_context *ctx,
 			       const struct _mesa_prim *prims,
 			       GLuint nr_prims,
diff --git a/src/mesa/vbo/vbo_context.c b/src/mesa/vbo/vbo_context.c
index e3eb286..1f0b46a 100644
--- a/src/mesa/vbo/vbo_context.c
+++ b/src/mesa/vbo/vbo_context.c
@@ -148,11 +148,30 @@ static void init_mat_currval(struct gl_context *ctx)
 }
 
 
+static void nop_resolve(struct gl_context *ctx)
+{
+}
+
+static void nop_draw(struct gl_context *ctx,
+                     const struct _mesa_prim *prims,
+                     GLuint nr_prims,
+                     const struct _mesa_index_buffer *ib,
+                     GLboolean index_bounds_valid,
+                     GLuint min_index,
+                     GLuint max_index,
+                     struct gl_transform_feedback_object *tfb_vertcount,
+                     unsigned stream,
+                     struct gl_buffer_object *indirect)
+{
+}
+
 GLboolean _vbo_CreateContext( struct gl_context *ctx )
 {
    struct vbo_context *vbo = CALLOC_STRUCT(vbo_context);
 
    ctx->vbo_context = vbo;
+   vbo->draw_prims = nop_draw;
+   vbo->resolve = nop_resolve;
 
    /* Initialize the arrayelt helper
     */
diff --git a/src/mesa/vbo/vbo_context.h b/src/mesa/vbo/vbo_context.h
index a376efe..c4033ee4 100644
--- a/src/mesa/vbo/vbo_context.h
+++ b/src/mesa/vbo/vbo_context.h
@@ -75,6 +75,7 @@ struct vbo_context {
    /* Callback into the driver.  This must always succeed, the driver
     * is responsible for initiating any fallback actions required:
     */
+   vbo_resolve_func resolve;
    vbo_draw_func draw_prims;
 };
 
diff --git a/src/mesa/vbo/vbo_exec_array.c b/src/mesa/vbo/vbo_exec_array.c
index 34d2c1d..d592ae4 100644
--- a/src/mesa/vbo/vbo_exec_array.c
+++ b/src/mesa/vbo/vbo_exec_array.c
@@ -549,6 +549,7 @@ vbo_bind_arrays(struct gl_context *ctx)
    struct vbo_context *vbo = vbo_context(ctx);
    struct vbo_exec_context *exec = &vbo->exec;
 
+   vbo->resolve(ctx);
    vbo_draw_method(vbo, DRAW_ARRAYS);
 
    if (exec->array.recalculate_inputs) {
diff --git a/src/mesa/vbo/vbo_exec_draw.c b/src/mesa/vbo/vbo_exec_draw.c
index 2bfb0c3..fa5b06b 100644
--- a/src/mesa/vbo/vbo_exec_draw.c
+++ b/src/mesa/vbo/vbo_exec_draw.c
@@ -388,11 +388,14 @@ vbo_exec_vtx_flush(struct vbo_exec_context *exec, GLboolean keepUnmapped)
 
       if (exec->vtx.copied.nr != exec->vtx.vert_count) {
 	 struct gl_context *ctx = exec->ctx;
+
+         vbo_context(ctx)->resolve( ctx );
 	 
 	 /* Before the update_state() as this may raise _NEW_VARYING_VP_INPUTS
           * from _mesa_set_varying_vp_inputs().
 	  */
-	 vbo_exec_bind_arrays( ctx );
+         vbo_draw_method( vbo_context(ctx), DRAW_BEGIN_END);
+         vbo_exec_bind_arrays( ctx );
 
          if (ctx->NewState)
             _mesa_update_state( ctx );
diff --git a/src/mesa/vbo/vbo_save_draw.c b/src/mesa/vbo/vbo_save_draw.c
index b1fd689..2103b8e 100644
--- a/src/mesa/vbo/vbo_save_draw.c
+++ b/src/mesa/vbo/vbo_save_draw.c
@@ -297,6 +297,8 @@ vbo_save_playback_vertex_list(struct gl_context *ctx, void *data)
          return;
       }
 
+      vbo_context(ctx)->resolve(ctx);
+
       vbo_bind_vertex_list( ctx, node );
 
       vbo_draw_method(vbo_context(ctx), DRAW_DISPLAY_LIST);
-- 
2.5.1