If the geometry shader is indeed using streams then we need 2 control data bits per vertex for the StreamID. If the shader is not using streams then we don't need control data bits. --- src/mesa/drivers/dri/i965/brw_vec4_gs.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/src/mesa/drivers/dri/i965/brw_vec4_gs.c b/src/mesa/drivers/dri/i965/brw_vec4_gs.c index b48c420..0b30c7d 100644 --- a/src/mesa/drivers/dri/i965/brw_vec4_gs.c +++ b/src/mesa/drivers/dri/i965/brw_vec4_gs.c @@ -81,10 +81,11 @@ do_gs_prog(struct brw_context *brw, */ c.prog_data.control_data_format = GEN7_GS_CONTROL_DATA_FORMAT_GSCTL_SID; - /* However, StreamID is not yet supported, so we output zero bits of - * control data per vertex. - */ - c.control_data_bits_per_vertex = 0; + /* We only have to emit control bits if we are using streams */ + if (prog->Geom.UsesStreams) + c.control_data_bits_per_vertex = 2; + else + c.control_data_bits_per_vertex = 0; } else { /* When the output type is triangle_strip or line_strip, EndPrimitive() * may be used to terminate the current strip and start a new one -- 1.9.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev