Mesa (gallium-0.2): gallium: added draw_texture_samplers() to support texture fetches from vertex shaders

[Brian Paul]

Module: Mesa
Branch: gallium-0.2
Commit: f2bccfd3c806a879abf0c40858806ec3825d0628
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=f2bccfd3c806a879abf0c40858806ec3825d0628

Author: Brian <brian.paul at tungstengraphics.com>
Date:   Tue Dec  2 22:38:46 2008 -0700

gallium: added draw_texture_samplers() to support texture fetches from vertex shaders

This may only be practical for the softpipe driver at this time.

---

 src/gallium/auxiliary/draw/draw_context.c |   15 +++++++++++++++
 src/gallium/auxiliary/draw/draw_context.h |    8 +++++++-
 src/gallium/auxiliary/draw/draw_private.h |    3 +++
 src/gallium/auxiliary/draw/draw_vs_exec.c |    4 ++--
 4 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/src/gallium/auxiliary/draw/draw_context.c b/src/gallium/auxiliary/draw/draw_context.c
index 41a4cba..b2a3481 100644
--- a/src/gallium/auxiliary/draw/draw_context.c
+++ b/src/gallium/auxiliary/draw/draw_context.c
@@ -331,6 +331,21 @@ draw_num_vs_outputs(const struct draw_context *draw)
 }
 
 
+/**
+ * Provide TGSI sampler objects for vertex shaders that use texture fetches.
+ * This might only be used by software drivers for the time being.
+ */
+void
+draw_texture_samplers(struct draw_context *draw,
+                      uint num_samplers,
+                      struct tgsi_sampler **samplers)
+{
+   draw->vs.num_samplers = num_samplers;
+   draw->vs.samplers = samplers;
+}
+
+
+
 
 void draw_set_render( struct draw_context *draw, 
 		      struct vbuf_render *render )
diff --git a/src/gallium/auxiliary/draw/draw_context.h b/src/gallium/auxiliary/draw/draw_context.h
index 3eeb453..8f5cecf 100644
--- a/src/gallium/auxiliary/draw/draw_context.h
+++ b/src/gallium/auxiliary/draw/draw_context.h
@@ -45,7 +45,7 @@ struct pipe_context;
 struct draw_context;
 struct draw_stage;
 struct draw_vertex_shader;
-
+struct tgsi_sampler;
 
 
 struct draw_context *draw_create( void );
@@ -91,6 +91,12 @@ uint
 draw_num_vs_outputs(const struct draw_context *draw);
 
 
+void
+draw_texture_samplers(struct draw_context *draw,
+                      uint num_samplers,
+                      struct tgsi_sampler **samplers);
+
+
 
 /*
  * Vertex shader functions
diff --git a/src/gallium/auxiliary/draw/draw_private.h b/src/gallium/auxiliary/draw/draw_private.h
index 5d53114..6097fff 100644
--- a/src/gallium/auxiliary/draw/draw_private.h
+++ b/src/gallium/auxiliary/draw/draw_private.h
@@ -185,6 +185,9 @@ struct draw_context
       /** TGSI program interpreter runtime state */
       struct tgsi_exec_machine machine;
 
+      uint num_samplers;
+      struct tgsi_sampler **samplers;
+
       /* This (and the tgsi_exec_machine struct) probably need to be moved somewhere private.
        */
       struct gallivm_cpu_engine *engine;   
diff --git a/src/gallium/auxiliary/draw/draw_vs_exec.c b/src/gallium/auxiliary/draw/draw_vs_exec.c
index 80c3606..b3200df 100644
--- a/src/gallium/auxiliary/draw/draw_vs_exec.c
+++ b/src/gallium/auxiliary/draw/draw_vs_exec.c
@@ -68,8 +68,8 @@ vs_exec_prepare( struct draw_vertex_shader *shader,
    if (evs->machine->Tokens != shader->state.tokens) {
       tgsi_exec_machine_bind_shader(evs->machine,
                                     shader->state.tokens,
-                                    PIPE_MAX_SAMPLERS,
-                                    NULL /*samplers*/ );
+                                    draw->vs.num_samplers,
+                                    draw->vs.samplers);
    }
 }