From db4ccc004a96255f3ad0dc26467f2243a133c24b Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Tue, 20 Apr 2010 11:43:58 -0600 Subject: llvmpipe: fix incorrect front-facing value for fragment shader The TGSI convention is +1 for front-facing, -1 for back-facing Fixes glean glsl1 gl_FrontFacing tests. --- src/gallium/drivers/llvmpipe/lp_setup_tri.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'src/gallium/drivers/llvmpipe/lp_setup_tri.c') diff --git a/src/gallium/drivers/llvmpipe/lp_setup_tri.c b/src/gallium/drivers/llvmpipe/lp_setup_tri.c index a95053444b..f8a5816573 100644 --- a/src/gallium/drivers/llvmpipe/lp_setup_tri.c +++ b/src/gallium/drivers/llvmpipe/lp_setup_tri.c @@ -163,12 +163,17 @@ setup_fragcoord_coef(struct lp_setup_context *setup, } +/** + * Setup the fragment input attribute with the front-facing value. + * \param frontface is the triangle front facing? + */ static void setup_facing_coef( struct lp_setup_context *setup, struct lp_rast_triangle *tri, unsigned slot, boolean frontface ) { - constant_coef( setup, tri, slot, 1.0f - frontface, 0 ); + /* convert TRUE to 1.0 and FALSE to -1.0 */ + constant_coef( setup, tri, slot, 2.0f * frontface - 1.0f, 0 ); constant_coef( setup, tri, slot, 0.0f, 1 ); /* wasted */ constant_coef( setup, tri, slot, 0.0f, 2 ); /* wasted */ constant_coef( setup, tri, slot, 0.0f, 3 ); /* wasted */ -- cgit v1.2.3