mesa: Compute effective buffer bindings in the vao.

Compute VAO buffer binding information past the position/generic0 mapping.
Scan for duplicate buffer bindings and collapse them into derived
effective buffer binding index and effective attribute mask variables.
Provide a set of helper functions to access the distilled
information in the VAO. All of them prefixed with _mesa_draw_...
to indicate that they are meant to query draw information.

v2: Also group user space arrays containing interleaved arrays.
    Add _Eff*Offset to be copied on attribute and binding copy.
    Update comments.

Reviewed-by: Brian Paul <[email protected]>
Signed-off-by: Mathias Fröhlich <[email protected]>

1 files changed, 17 insertions, 0 deletions

diff --git a/src/mesa/vbo/vbo_context.c b/src/mesa/vbo/vbo_context.c
index ada78ffd63b..cc6aada8610 100644
--- a/src/mesa/vbo/vbo_context.c
+++ b/src/mesa/vbo/vbo_context.c
@@ -234,6 +234,23 @@ _vbo_DestroyContext(struct gl_context *ctx)
 }
 
 
+const struct gl_array_attributes *
+_vbo_current_attrib(const struct gl_context *ctx, gl_vert_attrib attr)
+{
+   const struct vbo_context *vbo = vbo_context_const(ctx);
+   const gl_vertex_processing_mode vmp = ctx->VertexProgram._VPMode;
+   return &vbo->current[_vbo_attribute_alias_map[vmp][attr]];
+}
+
+
+const struct gl_vertex_buffer_binding *
+_vbo_current_binding(const struct gl_context *ctx)
+{
+   const struct vbo_context *vbo = vbo_context_const(ctx);
+   return &vbo->binding;
+}
+
+
 /*
  * Helper function for _vbo_draw_indirect below that additionally takes a zero
  * initialized array of _mesa_prim scratch space memory as the last argument.