*/
-#include "pipe/p_util.h"
+#include "util/u_memory.h"
#include "pipe/p_defines.h"
#include "draw_pipe.h"
struct cull_stage {
struct draw_stage stage;
- unsigned winding; /**< which winding(s) to cull (one of PIPE_WINDING_x) */
+ unsigned cull_face; /**< which face(s) to cull (one of PIPE_FACE_x) */
+ unsigned front_ccw;
};
}
-
-
static void cull_tri( struct draw_stage *stage,
struct prim_header *header )
{
+ const unsigned pos = draw_current_shader_position_output(stage->draw);
+
/* Window coords: */
- const float *v0 = header->v[0]->data[0];
- const float *v1 = header->v[1]->data[0];
- const float *v2 = header->v[2]->data[0];
+ const float *v0 = header->v[0]->data[pos];
+ const float *v1 = header->v[1]->data[pos];
+ const float *v2 = header->v[2]->data[pos];
- /* edge vectors e = v0 - v2, f = v1 - v2 */
+ /* edge vectors: e = v0 - v2, f = v1 - v2 */
const float ex = v0[0] - v2[0];
const float ey = v0[1] - v2[1];
const float fx = v1[0] - v2[0];
header->det = ex * fy - ey * fx;
if (header->det != 0) {
- /* if (det < 0 then Z points toward camera and triangle is
+ /* if det < 0 then Z points toward the camera and the triangle is
* counter-clockwise winding.
*/
- unsigned winding = (header->det < 0) ? PIPE_WINDING_CCW : PIPE_WINDING_CW;
+ unsigned ccw = (header->det < 0);
+ unsigned face = ((ccw == cull_stage(stage)->front_ccw) ?
+ PIPE_FACE_FRONT :
+ PIPE_FACE_BACK);
- if ((winding & cull_stage(stage)->winding) == 0) {
+ if ((face & cull_stage(stage)->cull_face) == 0) {
/* triangle is not culled, pass to next stage */
stage->next->tri( stage->next, header );
}
}
}
+
static void cull_first_tri( struct draw_stage *stage,
struct prim_header *header )
{
struct cull_stage *cull = cull_stage(stage);
- cull->winding = stage->draw->rasterizer->cull_mode;
+ cull->cull_face = stage->draw->rasterizer->cull_face;
+ cull->front_ccw = stage->draw->rasterizer->front_ccw;
stage->tri = cull_tri;
stage->tri( stage, header );
}
-
static void cull_flush( struct draw_stage *stage, unsigned flags )
{
stage->tri = cull_first_tri;
stage->next->flush( stage->next, flags );
}
+
static void cull_reset_stipple_counter( struct draw_stage *stage )
{
stage->next->reset_stipple_counter( stage->next );
struct draw_stage *draw_cull_stage( struct draw_context *draw )
{
struct cull_stage *cull = CALLOC_STRUCT(cull_stage);
-
- draw_alloc_temp_verts( &cull->stage, 0 );
+ if (cull == NULL)
+ goto fail;
cull->stage.draw = draw;
+ cull->stage.name = "cull";
cull->stage.next = NULL;
cull->stage.point = draw_pipe_passthrough_point;
cull->stage.line = draw_pipe_passthrough_line;
cull->stage.reset_stipple_counter = cull_reset_stipple_counter;
cull->stage.destroy = cull_destroy;
+ if (!draw_alloc_temp_verts( &cull->stage, 0 ))
+ goto fail;
+
return &cull->stage;
+
+fail:
+ if (cull)
+ cull->stage.destroy( &cull->stage );
+
+ return NULL;
}