diff options
author | Keith Whitwell <keith@tungstengraphics.com> | 2008-02-15 11:15:47 +0000 |
---|---|---|
committer | Keith Whitwell <keith@tungstengraphics.com> | 2008-02-15 11:15:47 +0000 |
commit | 6ac2c1cc0cd1253ba2014d459010032127f185ec (patch) | |
tree | 6348de9de19e7394800a983c8c614566d22b870b /src/gallium/aux/draw/draw_cull.c | |
parent | c04a7f8929d674971a472ffa4d3a31200c22aa5a (diff) | |
parent | 6d3831b11d9f5aaba61cc2fb8ade61437ad7c335 (diff) |
Merge commit 'origin/gallium-0.1' into gallium-0.1
Conflicts:
src/gallium/drivers/softpipe/sp_quad_fs.c
src/gallium/drivers/softpipe/sp_state.h
src/gallium/drivers/softpipe/sp_state_fs.c
Diffstat (limited to 'src/gallium/aux/draw/draw_cull.c')
-rw-r--r-- | src/gallium/aux/draw/draw_cull.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/src/gallium/aux/draw/draw_cull.c b/src/gallium/aux/draw/draw_cull.c new file mode 100644 index 0000000000..8177b0ac86 --- /dev/null +++ b/src/gallium/aux/draw/draw_cull.c @@ -0,0 +1,150 @@ +/************************************************************************** + * + * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas. + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. + * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR + * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, + * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE + * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + **************************************************************************/ + +/** + * \brief Drawing stage for polygon culling + */ + +/* Authors: Keith Whitwell <keith@tungstengraphics.com> + */ + + +#include "pipe/p_util.h" +#include "pipe/p_defines.h" +#include "draw_private.h" + + +struct cull_stage { + struct draw_stage stage; + unsigned winding; /**< which winding(s) to cull (one of PIPE_WINDING_x) */ +}; + + +static INLINE struct cull_stage *cull_stage( struct draw_stage *stage ) +{ + return (struct cull_stage *)stage; +} + + + + +static void cull_tri( struct draw_stage *stage, + struct prim_header *header ) +{ + /* 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]; + + /* 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]; + const float fy = v1[1] - v2[1]; + + /* det = cross(e,f).z */ + header->det = ex * fy - ey * fx; + + if (header->det != 0) { + /* if (det < 0 then Z points toward camera and triangle is + * counter-clockwise winding. + */ + unsigned winding = (header->det < 0) ? PIPE_WINDING_CCW : PIPE_WINDING_CW; + + if ((winding & cull_stage(stage)->winding) == 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; + + stage->tri = cull_tri; + stage->tri( stage, header ); +} + + + +static void cull_line( struct draw_stage *stage, + struct prim_header *header ) +{ + stage->next->line( stage->next, header ); +} + + +static void cull_point( struct draw_stage *stage, + struct prim_header *header ) +{ + stage->next->point( stage->next, 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 ); +} + + +static void cull_destroy( struct draw_stage *stage ) +{ + draw_free_temp_verts( stage ); + FREE( stage ); +} + + +/** + * Create a new polygon culling stage. + */ +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 ); + + cull->stage.draw = draw; + cull->stage.next = NULL; + cull->stage.point = cull_point; + cull->stage.line = cull_line; + cull->stage.tri = cull_first_tri; + cull->stage.flush = cull_flush; + cull->stage.reset_stipple_counter = cull_reset_stipple_counter; + cull->stage.destroy = cull_destroy; + + return &cull->stage; +} |