[Mesa-dev] [PATCH 2/3] i965/vs: Emit the vertex position a second time in the Gen5 VUE header.

[Kenneth Graunke]

The fragment shader needs gl_Position.w in order to do interpolation.
Both the comments above and the old VS backend emitted this.

Fixes a ton of piglit tests on Ironlake with the new VS.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
index 4babc56..04c49da 100644
--- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
@@ -1736,6 +1736,8 @@ vec4_visitor::emit_vue_header_gen4(int header_mrf)
 
       /* Pad so that vertex element data is aligned. */
       header_mrf++;
+
+      emit(BRW_OPCODE_MOV, brw_message_reg(header_mrf++), pos);
    } else {
       /* There are 8 dwords in VUE header pre-Ironlake:
        * dword 0-3 (m1) is indices, point width, clip flags.
-- 
1.7.6