[Mesa-dev] [PATCH] vbo: signal _NEW_ARRAY when transitioning between glBegin/End, glDrawArrays

[Brian Paul]

This fixes a regression seen with the isosurf demo when switching between
glBegin/End and glDrawArrays (do it several times).  The problem was the
driver wasn't getting _NEW_ARRAY when the arrays were subtly changed:
(vertex3f, normal3f) vs. (normal3f, vertex3f).

This patch fixes that by signaling _NEW_ARRAY whenever we transition
between glBegin/End and glDrawArrays mode.

The patch also fixes up the initialization of the map_vp_none[] array
to stop putting strange values in the last five elements of the array.
---
 src/mesa/vbo/vbo_context.c    |   11 ++++-------
 src/mesa/vbo/vbo_exec.h       |   33 +++++++++++++++++++++++++++++++++
 src/mesa/vbo/vbo_exec_api.c   |    2 ++
 src/mesa/vbo/vbo_exec_array.c |    4 ++++
 4 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/src/mesa/vbo/vbo_context.c b/src/mesa/vbo/vbo_context.c
index b2e6bbc..d83f2fd 100644
--- a/src/mesa/vbo/vbo_context.c
+++ b/src/mesa/vbo/vbo_context.c
@@ -176,17 +176,14 @@ GLboolean _vbo_CreateContext( struct gl_context *ctx )
    {
       GLuint i;
 
-      /* When no vertex program, pull in the material attributes in
-       * the generic range.
-       */
-      for (i = 0; i < VERT_ATTRIB_FF_MAX; i++) 
+      /* identity mapping */
+      for (i = 0; i < Elements(vbo->map_vp_none); i++) 
 	 vbo->map_vp_none[i] = i;
+      /* map material attribs to generic slots */
       for (i = 0; i < NR_MAT_ATTRIBS; i++) 
 	 vbo->map_vp_none[VERT_ATTRIB_GENERIC(i)]
             = VBO_ATTRIB_MAT_FRONT_AMBIENT + i;
-      for (i = NR_MAT_ATTRIBS; i < VERT_ATTRIB_GENERIC_MAX; i++)
-	 vbo->map_vp_none[VERT_ATTRIB_GENERIC(i)] = i;
-      
+
       for (i = 0; i < Elements(vbo->map_vp_arb); i++)
 	 vbo->map_vp_arb[i] = i;
    }
diff --git a/src/mesa/vbo/vbo_exec.h b/src/mesa/vbo/vbo_exec.h
index cfed8e8..339461d 100644
--- a/src/mesa/vbo/vbo_exec.h
+++ b/src/mesa/vbo/vbo_exec.h
@@ -78,12 +78,23 @@ struct vbo_exec_copied_vtx {
 };
 
 
+enum draw_method
+{
+   DRAW_NONE,
+   DRAW_BEGIN_END,
+   DRAW_ELEMENTS,
+   DRAW_ARRAYS
+};
+
+
 struct vbo_exec_context
 {
    struct gl_context *ctx;   
    GLvertexformat vtxfmt;
    GLvertexformat vtxfmt_noop;
 
+   enum draw_method last_draw_method;
+
    struct {
       struct gl_buffer_object *bufferobj;
 
@@ -164,6 +175,28 @@ void vbo_exec_array_destroy( struct vbo_exec_context *exec );
 void vbo_exec_vtx_init( struct vbo_exec_context *exec );
 void vbo_exec_vtx_destroy( struct vbo_exec_context *exec );
 
+
+/**
+ * This is called by glBegin, glDrawArrays and glDrawElements (and
+ * variations of those calls).  When we transition from immediate mode
+ * drawing to array drawing we need to invalidate the array state.
+ *
+ * glBegin/End builds vertex arrays.  Those arrays may look identical
+ * to glDrawArrays arrays except that the position of the elements may
+ * be different.  For example, arrays of (position3v, normal3f) vs. arrays
+ * of (normal3f, position3f).  So we need to make sure we notify drivers
+ * that arrays may be changing.
+ */
+static inline void
+vbo_draw_method(struct vbo_exec_context *exec, enum draw_method method)
+{
+   if (exec->last_draw_method != method) {
+      exec->ctx->NewState |= _NEW_ARRAY;
+      exec->last_draw_method = method;
+   }
+}
+
+
 #if FEATURE_beginend
 
 void vbo_exec_vtx_flush( struct vbo_exec_context *exec, GLboolean unmap );
diff --git a/src/mesa/vbo/vbo_exec_api.c b/src/mesa/vbo/vbo_exec_api.c
index 4be0169..cb5f9ae 100644
--- a/src/mesa/vbo/vbo_exec_api.c
+++ b/src/mesa/vbo/vbo_exec_api.c
@@ -701,6 +701,8 @@ static void GLAPIENTRY vbo_exec_Begin( GLenum mode )
          return;
       }
 
+      vbo_draw_method(exec, DRAW_BEGIN_END);
+
       if (ctx->Driver.PrepareExecBegin)
 	 ctx->Driver.PrepareExecBegin(ctx);
 
diff --git a/src/mesa/vbo/vbo_exec_array.c b/src/mesa/vbo/vbo_exec_array.c
index a6e41e9..e84c0f3 100644
--- a/src/mesa/vbo/vbo_exec_array.c
+++ b/src/mesa/vbo/vbo_exec_array.c
@@ -558,6 +558,8 @@ vbo_draw_arrays(struct gl_context *ctx, GLenum mode, GLint start,
 
    vbo_bind_arrays(ctx);
 
+   vbo_draw_method(exec, DRAW_ARRAYS);
+
    /* Again... because we may have changed the bitmask of per-vertex varying
     * attributes.  If we regenerate the fixed-function vertex program now
     * we may be able to prune down the number of vertex attributes which we
@@ -773,6 +775,8 @@ vbo_validated_drawrangeelements(struct gl_context *ctx, GLenum mode,
 
    vbo_bind_arrays( ctx );
 
+   vbo_draw_method(exec, DRAW_ELEMENTS);
+
    /* check for dirty state again */
    if (ctx->NewState)
       _mesa_update_state( ctx );
-- 
1.7.3.4