draw: inject frontface info into wireframe outputs

Draw module can decompose primitives into wireframe models, which
is a fancy word for 'lines', unfortunately that decomposition means
that we weren't able to preserve the original front-face info which
could be derived from the original primitives (lines don't have a
'face'). To fix it allow draw module to inject a fake face semantic
into outputs from which the backends can figure out the original
frontfacing info of the primitives.

Signed-off-by: Zack Rusin <[email protected]>
Reviewed-by: Roland Scheidegger <[email protected]>
Reviewed-by: Jose Fonseca <[email protected]>

1 files changed, 1 insertions, 0 deletions

diff --git a/src/gallium/drivers/r300/r300_state_derived.c b/src/gallium/drivers/r300/r300_state_derived.c
index 1013557bde9..da86cd2aaa5 100644
--- a/src/gallium/drivers/r300/r300_state_derived.c
+++ b/src/gallium/drivers/r300/r300_state_derived.c
@@ -1079,6 +1079,7 @@ void r300_update_derived_state(struct r300_context* r300)
 
         if (r300->draw) {
             memset(&r300->vertex_info, 0, sizeof(struct vertex_info));
+            draw_prepare_shader_outputs(r300->draw);
             r300_draw_emit_all_attribs(r300);
             draw_compute_vertex_size(&r300->vertex_info);
             r300_swtcl_vertex_psc(r300);