The new function, called get_vert_result(), uses the VUE map to find the register containing a given vertex attribute. Previously, we used the attr_to_idx[] array, which served the same purpose but didn't account for gl_PointSize correctly.
This fixes a bug on pre-Gen6 wherein the back side of a triangle would be rendered incorrectyl if the vertex shader wrote to gl_PointSize. --- src/mesa/drivers/dri/i965/brw_sf_emit.c | 23 ++++++++++++++--------- 1 files changed, 14 insertions(+), 9 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_sf_emit.c b/src/mesa/drivers/dri/i965/brw_sf_emit.c index f1fe567..f362e20 100644 --- a/src/mesa/drivers/dri/i965/brw_sf_emit.c +++ b/src/mesa/drivers/dri/i965/brw_sf_emit.c @@ -55,12 +55,17 @@ static inline int vert_reg_to_vert_result(struct brw_sf_compile *c, GLuint reg, return c->vue_map.slot_to_vert_result[vue_slot]; } -static struct brw_reg get_vert_attr(struct brw_sf_compile *c, - struct brw_reg vert, - GLuint attr) +/** + * Determine the register corresponding to the given vert_result. + */ +static struct brw_reg get_vert_result(struct brw_sf_compile *c, + struct brw_reg vert, + GLuint vert_result) { - GLuint off = c->attr_to_idx[attr] / 2; - GLuint sub = c->attr_to_idx[attr] % 2; + int vue_slot = c->vue_map.vert_result_to_slot[vert_result]; + assert (vue_slot >= c->urb_entry_read_offset); + GLuint off = vue_slot / 2 - c->urb_entry_read_offset; + GLuint sub = vue_slot % 2; return brw_vec4_grf(vert.nr + off, sub * 4); } @@ -84,8 +89,8 @@ static void copy_bfc( struct brw_sf_compile *c, if (have_attr(c, VERT_RESULT_COL0+i) && have_attr(c, VERT_RESULT_BFC0+i)) brw_MOV(p, - get_vert_attr(c, vert, VERT_RESULT_COL0+i), - get_vert_attr(c, vert, VERT_RESULT_BFC0+i)); + get_vert_result(c, vert, VERT_RESULT_COL0+i), + get_vert_result(c, vert, VERT_RESULT_BFC0+i)); } } @@ -146,8 +151,8 @@ static void copy_colors( struct brw_sf_compile *c, for (i = VERT_RESULT_COL0; i <= VERT_RESULT_COL1; i++) { if (have_attr(c,i)) brw_MOV(p, - get_vert_attr(c, dst, i), - get_vert_attr(c, src, i)); + get_vert_result(c, dst, i), + get_vert_result(c, src, i)); } } -- 1.7.6 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev