ss_tritmp.h revision 0a9187801505130738ae947c69cafa8a1dd118d1
1/*
2 * Mesa 3-D graphics library
3 * Version:  7.1
4 *
5 * Copyright (C) 1999-2007  Brian Paul   All Rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included
15 * in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
18 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
21 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23 *
24 * Authors:
25 *    Keith Whitwell <keith@tungstengraphics.com>
26 */
27
28
29/**
30 * This is where we handle assigning vertex colors based on front/back
31 * facing, compute polygon offset and handle glPolygonMode().
32 */
33static void TAG(triangle)(GLcontext *ctx, GLuint e0, GLuint e1, GLuint e2 )
34{
35   struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
36   SScontext *swsetup = SWSETUP_CONTEXT(ctx);
37   SWvertex *verts = SWSETUP_CONTEXT(ctx)->verts;
38   SWvertex *v[3];
39   GLfloat z[3];
40   GLfloat offset, oz0, oz1, oz2;
41   GLenum mode = GL_FILL;
42   GLuint facing = 0;
43   GLchan saved_color[3][4];
44   GLfloat saved_col0[3][4];
45   GLfloat saved_spec[3][4];
46   GLfloat saved_index[3];
47
48   v[0] = &verts[e0];
49   v[1] = &verts[e1];
50   v[2] = &verts[e2];
51
52   if (IND & (SS_TWOSIDE_BIT | SS_OFFSET_BIT | SS_UNFILLED_BIT))
53   {
54      GLfloat ex = v[0]->attrib[FRAG_ATTRIB_WPOS][0] - v[2]->attrib[FRAG_ATTRIB_WPOS][0];
55      GLfloat ey = v[0]->attrib[FRAG_ATTRIB_WPOS][1] - v[2]->attrib[FRAG_ATTRIB_WPOS][1];
56      GLfloat fx = v[1]->attrib[FRAG_ATTRIB_WPOS][0] - v[2]->attrib[FRAG_ATTRIB_WPOS][0];
57      GLfloat fy = v[1]->attrib[FRAG_ATTRIB_WPOS][1] - v[2]->attrib[FRAG_ATTRIB_WPOS][1];
58      GLfloat cc  = ex*fy - ey*fx;
59
60      if (IND & (SS_TWOSIDE_BIT | SS_UNFILLED_BIT))
61      {
62	 facing = (cc < 0.0) ^ ctx->Polygon._FrontBit;
63
64	 if (IND & SS_UNFILLED_BIT)
65	    mode = facing ? ctx->Polygon.BackMode : ctx->Polygon.FrontMode;
66
67	 if (facing == 1) {
68	    if (IND & SS_TWOSIDE_BIT) {
69	       if (IND & SS_RGBA_BIT) {
70                  if (VB->BackfaceColorPtr) {
71                     GLfloat (*vbcolor)[4] = VB->BackfaceColorPtr->data;
72
73                     if (swsetup->intColors) {
74                        COPY_CHAN4(saved_color[0], v[0]->color);
75                        COPY_CHAN4(saved_color[1], v[1]->color);
76                        COPY_CHAN4(saved_color[2], v[2]->color);
77                     }
78                     else {
79                        COPY_4V(saved_col0[0], v[0]->attrib[FRAG_ATTRIB_COL0]);
80                        COPY_4V(saved_col0[1], v[1]->attrib[FRAG_ATTRIB_COL0]);
81                        COPY_4V(saved_col0[2], v[2]->attrib[FRAG_ATTRIB_COL0]);
82                     }
83
84                     if (VB->BackfaceColorPtr->stride) {
85                        if (swsetup->intColors) {
86                           SS_COLOR(v[0]->color, vbcolor[e0]);
87                           SS_COLOR(v[1]->color, vbcolor[e1]);
88                           SS_COLOR(v[2]->color, vbcolor[e2]);
89                        }
90                        else {
91                           COPY_4V(v[0]->attrib[FRAG_ATTRIB_COL0], vbcolor[e0]);
92                           COPY_4V(v[1]->attrib[FRAG_ATTRIB_COL0], vbcolor[e1]);
93                           COPY_4V(v[2]->attrib[FRAG_ATTRIB_COL0], vbcolor[e2]);
94                        }
95                     }
96                     else {
97                        /* flat shade */
98                        if (swsetup->intColors) {
99                           SS_COLOR(v[0]->color, vbcolor[0]);
100                           SS_COLOR(v[1]->color, vbcolor[0]);
101                           SS_COLOR(v[2]->color, vbcolor[0]);
102                        }
103                        else {
104                           COPY_4V(v[0]->attrib[FRAG_ATTRIB_COL0], vbcolor[0]);
105                           COPY_4V(v[1]->attrib[FRAG_ATTRIB_COL0], vbcolor[0]);
106                           COPY_4V(v[2]->attrib[FRAG_ATTRIB_COL0], vbcolor[0]);
107                        }
108                     }
109                  }
110
111		  if (VB->BackfaceSecondaryColorPtr) {
112		     GLfloat (*vbspec)[4] = VB->BackfaceSecondaryColorPtr->data;
113
114		     COPY_4V(saved_spec[0], v[0]->attrib[FRAG_ATTRIB_COL1]);
115		     COPY_4V(saved_spec[1], v[1]->attrib[FRAG_ATTRIB_COL1]);
116		     COPY_4V(saved_spec[2], v[2]->attrib[FRAG_ATTRIB_COL1]);
117
118		     if (VB->BackfaceSecondaryColorPtr->stride) {
119			SS_SPEC(v[0]->attrib[FRAG_ATTRIB_COL1], vbspec[e0]);
120			SS_SPEC(v[1]->attrib[FRAG_ATTRIB_COL1], vbspec[e1]);
121			SS_SPEC(v[2]->attrib[FRAG_ATTRIB_COL1], vbspec[e2]);
122		     }
123		     else {
124			SS_SPEC(v[0]->attrib[FRAG_ATTRIB_COL1], vbspec[0]);
125			SS_SPEC(v[1]->attrib[FRAG_ATTRIB_COL1], vbspec[0]);
126			SS_SPEC(v[2]->attrib[FRAG_ATTRIB_COL1], vbspec[0]);
127		     }
128		  }
129	       } else {
130		  GLfloat *vbindex = (GLfloat *)VB->BackfaceIndexPtr->data;
131		  saved_index[0] = v[0]->attrib[FRAG_ATTRIB_CI][0];
132		  saved_index[1] = v[1]->attrib[FRAG_ATTRIB_CI][0];
133		  saved_index[2] = v[2]->attrib[FRAG_ATTRIB_CI][0];
134
135		  SS_IND(v[0]->attrib[FRAG_ATTRIB_CI][0], (GLuint) vbindex[e0]);
136		  SS_IND(v[1]->attrib[FRAG_ATTRIB_CI][0], (GLuint) vbindex[e1]);
137		  SS_IND(v[2]->attrib[FRAG_ATTRIB_CI][0], (GLuint) vbindex[e2]);
138	       }
139	    }
140	 }
141      }
142
143      if (IND & SS_OFFSET_BIT) {
144         const GLfloat max = ctx->DrawBuffer->_DepthMaxF;
145         /* save original Z values (restored later) */
146	 z[0] = v[0]->attrib[FRAG_ATTRIB_WPOS][2];
147	 z[1] = v[1]->attrib[FRAG_ATTRIB_WPOS][2];
148	 z[2] = v[2]->attrib[FRAG_ATTRIB_WPOS][2];
149         /* Note that Z values are already scaled to [0,65535] (for example)
150          * so no MRD value is used here.
151          */
152	 offset = ctx->Polygon.OffsetUnits;
153	 if (cc * cc > 1e-16) {
154	    const GLfloat ez = z[0] - z[2];
155	    const GLfloat fz = z[1] - z[2];
156	    const GLfloat oneOverArea = 1.0F / cc;
157	    const GLfloat dzdx = FABSF((ey * fz - ez * fy) * oneOverArea);
158	    const GLfloat dzdy = FABSF((ez * fx - ex * fz) * oneOverArea);
159	    offset += MAX2(dzdx, dzdy) * ctx->Polygon.OffsetFactor;
160	 }
161         /* new Z values */
162         oz0 = CLAMP(v[0]->attrib[FRAG_ATTRIB_WPOS][2] + offset, 0.0, max);
163         oz1 = CLAMP(v[1]->attrib[FRAG_ATTRIB_WPOS][2] + offset, 0.0, max);
164         oz2 = CLAMP(v[2]->attrib[FRAG_ATTRIB_WPOS][2] + offset, 0.0, max);
165      }
166   }
167
168   if (mode == GL_POINT) {
169      if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetPoint) {
170	 v[0]->attrib[FRAG_ATTRIB_WPOS][2] = oz0;
171	 v[1]->attrib[FRAG_ATTRIB_WPOS][2] = oz1;
172	 v[2]->attrib[FRAG_ATTRIB_WPOS][2] = oz2;
173      }
174      _swsetup_render_tri(ctx, e0, e1, e2, facing, _swsetup_edge_render_point_tri);
175   } else if (mode == GL_LINE) {
176      if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetLine) {
177	 v[0]->attrib[FRAG_ATTRIB_WPOS][2] = oz0;
178	 v[1]->attrib[FRAG_ATTRIB_WPOS][2] = oz1;
179	 v[2]->attrib[FRAG_ATTRIB_WPOS][2] = oz2;
180      }
181      _swsetup_render_tri(ctx, e0, e1, e2, facing, _swsetup_edge_render_line_tri);
182   } else {
183      if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetFill) {
184	 v[0]->attrib[FRAG_ATTRIB_WPOS][2] = oz0;
185	 v[1]->attrib[FRAG_ATTRIB_WPOS][2] = oz1;
186	 v[2]->attrib[FRAG_ATTRIB_WPOS][2] = oz2;
187      }
188      _swrast_Triangle( ctx, v[0], v[1], v[2] );
189   }
190
191   /*
192    * Restore original vertex colors, etc.
193    */
194   if (IND & SS_OFFSET_BIT) {
195      v[0]->attrib[FRAG_ATTRIB_WPOS][2] = z[0];
196      v[1]->attrib[FRAG_ATTRIB_WPOS][2] = z[1];
197      v[2]->attrib[FRAG_ATTRIB_WPOS][2] = z[2];
198   }
199
200   if (IND & SS_TWOSIDE_BIT) {
201      if (facing == 1) {
202	 if (IND & SS_RGBA_BIT) {
203            if (VB->BackfaceColorPtr) {
204               if (swsetup->intColors) {
205                  COPY_CHAN4(v[0]->color, saved_color[0]);
206                  COPY_CHAN4(v[1]->color, saved_color[1]);
207                  COPY_CHAN4(v[2]->color, saved_color[2]);
208               }
209               else {
210                  COPY_4V(v[0]->attrib[FRAG_ATTRIB_COL0], saved_col0[0]);
211                  COPY_4V(v[1]->attrib[FRAG_ATTRIB_COL0], saved_col0[1]);
212                  COPY_4V(v[2]->attrib[FRAG_ATTRIB_COL0], saved_col0[2]);
213               }
214            }
215
216	    if (VB->BackfaceSecondaryColorPtr) {
217	       COPY_4V(v[0]->attrib[FRAG_ATTRIB_COL1], saved_spec[0]);
218	       COPY_4V(v[1]->attrib[FRAG_ATTRIB_COL1], saved_spec[1]);
219	       COPY_4V(v[2]->attrib[FRAG_ATTRIB_COL1], saved_spec[2]);
220	    }
221	 } else {
222	    v[0]->attrib[FRAG_ATTRIB_CI][0] = saved_index[0];
223	    v[1]->attrib[FRAG_ATTRIB_CI][0] = saved_index[1];
224	    v[2]->attrib[FRAG_ATTRIB_CI][0] = saved_index[2];
225	 }
226      }
227   }
228}
229
230
231
232/* Need to fixup edgeflags when decomposing to triangles:
233 */
234static void TAG(quadfunc)( GLcontext *ctx, GLuint v0,
235		       GLuint v1, GLuint v2, GLuint v3 )
236{
237   if (IND & SS_UNFILLED_BIT) {
238      struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
239      if (VB->EdgeFlag) { /* XXX this test shouldn't be needed (bug 12614) */
240         GLubyte ef1 = VB->EdgeFlag[v1];
241         GLubyte ef3 = VB->EdgeFlag[v3];
242         VB->EdgeFlag[v1] = 0;
243         TAG(triangle)( ctx, v0, v1, v3 );
244         VB->EdgeFlag[v1] = ef1;
245         VB->EdgeFlag[v3] = 0;
246         TAG(triangle)( ctx, v1, v2, v3 );
247         VB->EdgeFlag[v3] = ef3;
248      }
249   } else {
250      TAG(triangle)( ctx, v0, v1, v3 );
251      TAG(triangle)( ctx, v1, v2, v3 );
252   }
253}
254
255
256
257
258static void TAG(init)( void )
259{
260   tri_tab[IND] = TAG(triangle);
261   quad_tab[IND] = TAG(quadfunc);
262}
263
264
265#undef IND
266#undef TAG
267