diff options
author | José Fonseca <jrfonseca@tungstengraphics.com> | 2008-02-15 17:35:24 +0900 |
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committer | José Fonseca <jrfonseca@tungstengraphics.com> | 2008-02-15 17:45:40 +0900 |
commit | b642730be93149baa7556e5791393168ab396175 (patch) | |
tree | 67d174be5d4814261b93bc8b20c027a26d1c3d06 /src/gallium/aux/draw/draw_offset.c | |
parent | 4593be34b2a6e494f0e476c8aa8e1d2633fffd47 (diff) |
Code reorganization: move files into their places.
This is in a separate commit to ensure renames are properly preserved.
Diffstat (limited to 'src/gallium/aux/draw/draw_offset.c')
-rw-r--r-- | src/gallium/aux/draw/draw_offset.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/src/gallium/aux/draw/draw_offset.c b/src/gallium/aux/draw/draw_offset.c new file mode 100644 index 0000000000..dbc676deae --- /dev/null +++ b/src/gallium/aux/draw/draw_offset.c @@ -0,0 +1,186 @@ +/************************************************************************** + * + * 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 polygon offset state + * + * \author Keith Whitwell <keith@tungstengraphics.com> + * \author Brian Paul + */ + +#include "pipe/p_util.h" +#include "draw_private.h" + + + +struct offset_stage { + struct draw_stage stage; + + float scale; + float units; +}; + + + +static INLINE struct offset_stage *offset_stage( struct draw_stage *stage ) +{ + return (struct offset_stage *) stage; +} + + + + + +/** + * Offset tri Z. Some hardware can handle this, but not usually when + * doing unfilled rendering. + */ +static void do_offset_tri( struct draw_stage *stage, + struct prim_header *header ) +{ + struct offset_stage *offset = offset_stage(stage); + float inv_det = 1.0f / header->det; + + /* Window coords: + */ + float *v0 = header->v[0]->data[0]; + float *v1 = header->v[1]->data[0]; + float *v2 = header->v[2]->data[0]; + + /* edge vectors e = v0 - v2, f = v1 - v2 */ + float ex = v0[0] - v2[0]; + float ey = v0[1] - v2[1]; + float ez = v0[2] - v2[2]; + float fx = v1[0] - v2[0]; + float fy = v1[1] - v2[1]; + float fz = v1[2] - v2[2]; + + /* (a,b) = cross(e,f).xy */ + float a = ey*fz - ez*fy; + float b = ez*fx - ex*fz; + + float dzdx = FABSF(a * inv_det); + float dzdy = FABSF(b * inv_det); + + float zoffset = offset->units + MAX2(dzdx, dzdy) * offset->scale; + + /* + * Note: we're applying the offset and clamping per-vertex. + * Ideally, the offset is applied per-fragment prior to fragment shading. + */ + v0[2] = CLAMP(v0[2] + zoffset, 0.0f, 1.0f); + v1[2] = CLAMP(v1[2] + zoffset, 0.0f, 1.0f); + v2[2] = CLAMP(v2[2] + zoffset, 0.0f, 1.0f); + + stage->next->tri( stage->next, header ); +} + + +static void offset_tri( struct draw_stage *stage, + struct prim_header *header ) +{ + struct prim_header tmp; + + tmp.det = header->det; + tmp.edgeflags = header->edgeflags; + tmp.v[0] = dup_vert(stage, header->v[0], 0); + tmp.v[1] = dup_vert(stage, header->v[1], 1); + tmp.v[2] = dup_vert(stage, header->v[2], 2); + + do_offset_tri( stage, &tmp ); +} + + +static void offset_first_tri( struct draw_stage *stage, + struct prim_header *header ) +{ + struct offset_stage *offset = offset_stage(stage); + float mrd = 1.0f / 65535.0f; /* XXX this depends on depthbuffer bits! */ + + offset->units = stage->draw->rasterizer->offset_units * mrd; + offset->scale = stage->draw->rasterizer->offset_scale; + + stage->tri = offset_tri; + stage->tri( stage, header ); +} + + +static void offset_line( struct draw_stage *stage, + struct prim_header *header ) +{ + stage->next->line( stage->next, header ); +} + + +static void offset_point( struct draw_stage *stage, + struct prim_header *header ) +{ + stage->next->point( stage->next, header ); +} + + +static void offset_flush( struct draw_stage *stage, + unsigned flags ) +{ + stage->tri = offset_first_tri; + stage->next->flush( stage->next, flags ); +} + + +static void offset_reset_stipple_counter( struct draw_stage *stage ) +{ + stage->next->reset_stipple_counter( stage->next ); +} + + +static void offset_destroy( struct draw_stage *stage ) +{ + draw_free_temp_verts( stage ); + FREE( stage ); +} + + +/** + * Create polygon offset drawing stage. + */ +struct draw_stage *draw_offset_stage( struct draw_context *draw ) +{ + struct offset_stage *offset = CALLOC_STRUCT(offset_stage); + + draw_alloc_temp_verts( &offset->stage, 3 ); + + offset->stage.draw = draw; + offset->stage.next = NULL; + offset->stage.point = offset_point; + offset->stage.line = offset_line; + offset->stage.tri = offset_first_tri; + offset->stage.flush = offset_flush; + offset->stage.reset_stipple_counter = offset_reset_stipple_counter; + offset->stage.destroy = offset_destroy; + + return &offset->stage; +} |