diff options
| -rw-r--r-- | src/gallium/drivers/llvmpipe/lp_setup_tri.c | 79 |
1 files changed, 39 insertions, 40 deletions
diff --git a/src/gallium/drivers/llvmpipe/lp_setup_tri.c b/src/gallium/drivers/llvmpipe/lp_setup_tri.c index eeffbb5fee..0d57f13f61 100644 --- a/src/gallium/drivers/llvmpipe/lp_setup_tri.c +++ b/src/gallium/drivers/llvmpipe/lp_setup_tri.c @@ -228,7 +228,6 @@ do_triangle_ccw(struct lp_setup_context *setup, struct lp_rast_triangle *tri; int x[3]; int y[3]; - int area; struct u_rect bbox; unsigned tri_bytes; int i; @@ -312,21 +311,8 @@ do_triangle_ccw(struct lp_setup_context *setup, tri->plane[1].dcdx = y[1] - y[2]; tri->plane[2].dcdx = y[2] - y[0]; - area = (tri->plane[0].dcdy * tri->plane[2].dcdx - - tri->plane[2].dcdy * tri->plane[0].dcdx); - LP_COUNT(nr_tris); - /* Cull non-ccw and zero-sized triangles. - * - * XXX: subject to overflow?? - */ - if (area <= 0) { - lp_scene_putback_data( scene, tri_bytes ); - LP_COUNT(nr_culled_tris); - return TRUE; - } - /* Setup parameter interpolants: */ lp_setup_tri_coef( setup, &tri->inputs, v0, v1, v2, frontfacing ); @@ -635,23 +621,36 @@ fail: /** - * Draw triangle if it's CW, cull otherwise. + * Try to draw the triangle, restart the scene on failure. */ -static void triangle_cw( struct lp_setup_context *setup, - const float (*v0)[4], - const float (*v1)[4], - const float (*v2)[4] ) +static void retry_triangle_ccw( struct lp_setup_context *setup, + const float (*v0)[4], + const float (*v1)[4], + const float (*v2)[4], + boolean front) { - if (!do_triangle_ccw( setup, v1, v0, v2, !setup->ccw_is_frontface )) + if (!do_triangle_ccw( setup, v0, v1, v2, front )) { if (!lp_setup_flush_and_restart(setup)) return; - if (!do_triangle_ccw( setup, v1, v0, v2, !setup->ccw_is_frontface )) + if (!do_triangle_ccw( setup, v0, v1, v2, front )) return; } } +static INLINE float +calc_area(const float (*v0)[4], + const float (*v1)[4], + const float (*v2)[4]) +{ + float dx01 = v0[0][0] - v1[0][0]; + float dy01 = v0[0][1] - v1[0][1]; + float dx20 = v2[0][0] - v0[0][0]; + float dy20 = v2[0][1] - v0[0][1]; + return dx01 * dy20 - dx20 * dy01; +} + /** * Draw triangle if it's CW, cull otherwise. @@ -661,17 +660,23 @@ static void triangle_cw( struct lp_setup_context *setup, const float (*v1)[4], const float (*v2)[4] ) { - if (!do_triangle_ccw( setup, v0, v1, v2, setup->ccw_is_frontface )) - { - if (!lp_setup_flush_and_restart(setup)) - return; + float area = calc_area(v0, v1, v2); - if (!do_triangle_ccw( setup, v0, v1, v2, setup->ccw_is_frontface )) - return; - } + if (area < 0.0f) + retry_triangle_ccw(setup, v0, v2, v1, !setup->ccw_is_frontface); } +static void triangle_ccw( struct lp_setup_context *setup, + const float (*v0)[4], + const float (*v1)[4], + const float (*v2)[4]) +{ + float area = calc_area(v0, v1, v2); + + if (area > 0.0f) + retry_triangle_ccw(setup, v0, v1, v2, setup->ccw_is_frontface); +} /** * Draw triangle whether it's CW or CCW. @@ -681,18 +686,12 @@ static void triangle_both( struct lp_setup_context *setup, const float (*v1)[4], const float (*v2)[4] ) { - /* edge vectors e = v0 - v2, f = v1 - v2 */ - const float ex = v0[0][0] - v2[0][0]; - const float ey = v0[0][1] - v2[0][1]; - const float fx = v1[0][0] - v2[0][0]; - const float fy = v1[0][1] - v2[0][1]; - - /* det = cross(e,f).z */ - const float det = ex * fy - ey * fx; - if (det < 0.0f) - triangle_ccw( setup, v0, v1, v2 ); - else if (det > 0.0f) - triangle_cw( setup, v0, v1, v2 ); + float area = calc_area(v0, v1, v2); + + if (area > 0.0f) + retry_triangle_ccw( setup, v0, v1, v2, setup->ccw_is_frontface ); + else if (area < 0.0f) + retry_triangle_ccw( setup, v0, v2, v1, !setup->ccw_is_frontface ); } |