src/mesa/swrast_setup/ss_tritmp.h

   1
   2 /*
   3  * Mesa 3-D graphics library
   4  * Version:  5.0
   5  *
   6  * Copyright (C) 1999-2002  Brian Paul   All Rights Reserved.
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included
  16  * in all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  21  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  22  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  24  *
  25  * Authors:
  26  *    Keith Whitwell <keith@tungstengraphics.com>
  27  */
  28
  29
  30 static void TAG(triangle)(GLcontext *ctx, GLuint e0, GLuint e1, GLuint e2 )
  31 {
  32    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
  33    SWvertex *verts = SWSETUP_CONTEXT(ctx)->verts;
  34    SWvertex *v[3];
  35    GLfloat z[3];
  36    GLfloat offset;
  37    GLenum mode = GL_FILL;
  38    GLuint facing = 0;
  39    GLchan saved_color[3][4];
  40    GLchan saved_spec[3][4];
  41    GLuint saved_index[3];
  42
  43    v[0] = &verts[e0];
  44    v[1] = &verts[e1];
  45    v[2] = &verts[e2];
  46
  47
  48    if (IND & (SS_TWOSIDE_BIT | SS_OFFSET_BIT | SS_UNFILLED_BIT))
  49    {
  50       GLfloat ex = v[0]->win[0] - v[2]->win[0];
  51       GLfloat ey = v[0]->win[1] - v[2]->win[1];
  52       GLfloat fx = v[1]->win[0] - v[2]->win[0];
  53       GLfloat fy = v[1]->win[1] - v[2]->win[1];
  54       GLfloat cc  = ex*fy - ey*fx;
  55
  56       if (IND & (SS_TWOSIDE_BIT | SS_UNFILLED_BIT))
  57       {
  58          facing = (cc < 0.0) ^ ctx->Polygon._FrontBit;
  59          if (ctx->Stencil.TestTwoSide)
  60             ctx->_Facing = facing; /* for 2-sided stencil test */
  61
  62          if (IND & SS_UNFILLED_BIT)
  63             mode = facing ? ctx->Polygon.BackMode : ctx->Polygon.FrontMode;
  64
  65          if (facing == 1) {
  66             if (IND & SS_TWOSIDE_BIT) {
  67                if (IND & SS_RGBA_BIT) {
  68                   GLfloat (*vbcolor)[4] = VB->ColorPtr[1]->data;
  69
  70                   COPY_CHAN4(saved_color[0], v[0]->color);
  71                   COPY_CHAN4(saved_color[1], v[1]->color);
  72                   COPY_CHAN4(saved_color[2], v[2]->color);
  73
  74                   SS_COLOR(v[0]->color, vbcolor[e0]);
  75                   SS_COLOR(v[1]->color, vbcolor[e1]);
  76                   SS_COLOR(v[2]->color, vbcolor[e2]);
  77
  78                   if (VB->SecondaryColorPtr[1]) {
  79                      GLfloat (*vbspec)[4] = VB->SecondaryColorPtr[1]->data;
  80
  81                      COPY_CHAN4(saved_spec[0], v[0]->specular);
  82                      COPY_CHAN4(saved_spec[1], v[1]->specular);
  83                      COPY_CHAN4(saved_spec[2], v[2]->specular);
  84
  85                      SS_SPEC(v[0]->specular, vbspec[e0]);
  86                      SS_SPEC(v[1]->specular, vbspec[e1]);
  87                      SS_SPEC(v[2]->specular, vbspec[e2]);
  88                   }
  89                } else {
  90                   GLfloat *vbindex = (GLfloat *)VB->IndexPtr[1]->data;
  91                   saved_index[0] = v[0]->index;
  92                   saved_index[1] = v[1]->index;
  93                   saved_index[2] = v[2]->index;
  94
  95                   SS_IND(v[0]->index, (GLuint) vbindex[e0]);
  96                   SS_IND(v[1]->index, (GLuint) vbindex[e1]);
  97                   SS_IND(v[2]->index, (GLuint) vbindex[e2]);
  98                }
  99             }
 100          }
 101       }
 102
 103       if (IND & SS_OFFSET_BIT)
 104       {
 105          offset = ctx->Polygon.OffsetUnits;
 106          z[0] = v[0]->win[2];
 107          z[1] = v[1]->win[2];
 108          z[2] = v[2]->win[2];
 109          if (cc * cc > 1e-16) {
 110             GLfloat ez = z[0] - z[2];
 111             GLfloat fz = z[1] - z[2];
 112             GLfloat a = ey*fz - ez*fy;
 113             GLfloat b = ez*fx - ex*fz;
 114             GLfloat ic = 1.0F / cc;
 115             GLfloat ac = a * ic;
 116             GLfloat bc = b * ic;
 117             if (ac < 0.0F) ac = -ac;
 118             if (bc < 0.0F) bc = -bc;
 119             offset += MAX2(ac, bc) * ctx->Polygon.OffsetFactor;
 120          }
 121          offset *= ctx->MRD;
 122          /*printf("offset %g\n", offset);*/
 123       }
 124    }
 125
 126    if (mode == GL_POINT) {
 127       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetPoint) {
 128          v[0]->win[2] += offset;
 129          v[1]->win[2] += offset;
 130          v[2]->win[2] += offset;
 131       }
 132       _swsetup_render_point_tri( ctx, e0, e1, e2, facing );
 133    } else if (mode == GL_LINE) {
 134       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetLine) {
 135          v[0]->win[2] += offset;
 136          v[1]->win[2] += offset;
 137          v[2]->win[2] += offset;
 138       }
 139       _swsetup_render_line_tri( ctx, e0, e1, e2, facing );
 140    } else {
 141       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetFill) {
 142          v[0]->win[2] += offset;
 143          v[1]->win[2] += offset;
 144          v[2]->win[2] += offset;
 145       }
 146       _swrast_Triangle( ctx, v[0], v[1], v[2] );
 147    }
 148
 149    if (IND & SS_OFFSET_BIT) {
 150       v[0]->win[2] = z[0];
 151       v[1]->win[2] = z[1];
 152       v[2]->win[2] = z[2];
 153    }
 154
 155    if (IND & SS_TWOSIDE_BIT) {
 156       if (facing == 1) {
 157          if (IND & SS_RGBA_BIT) {
 158             COPY_CHAN4(v[0]->color, saved_color[0]);
 159             COPY_CHAN4(v[1]->color, saved_color[1]);
 160             COPY_CHAN4(v[2]->color, saved_color[2]);
 161             if (VB->SecondaryColorPtr[1]) {
 162                COPY_CHAN4(v[0]->specular, saved_spec[0]);
 163                COPY_CHAN4(v[1]->specular, saved_spec[1]);
 164                COPY_CHAN4(v[2]->specular, saved_spec[2]);
 165             }
 166          } else {
 167             v[0]->index = saved_index[0];
 168             v[1]->index = saved_index[1];
 169             v[2]->index = saved_index[2];
 170          }
 171       }
 172    }
 173 }
 174
 175
 176
 177 /* Need to fixup edgeflags when decomposing to triangles:
 178  */
 179 static void TAG(quadfunc)( GLcontext *ctx, GLuint v0,
 180                        GLuint v1, GLuint v2, GLuint v3 )
 181 {
 182    if (IND & SS_UNFILLED_BIT) {
 183       struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
 184       GLubyte ef1 = VB->EdgeFlag[v1];
 185       GLubyte ef3 = VB->EdgeFlag[v3];
 186       VB->EdgeFlag[v1] = 0;
 187       TAG(triangle)( ctx, v0, v1, v3 );
 188       VB->EdgeFlag[v1] = ef1;
 189       VB->EdgeFlag[v3] = 0;
 190       TAG(triangle)( ctx, v1, v2, v3 );
 191       VB->EdgeFlag[v3] = ef3;
 192    } else {
 193       TAG(triangle)( ctx, v0, v1, v3 );
 194       TAG(triangle)( ctx, v1, v2, v3 );
 195    }
 196 }
 197
 198
 199
 200
 201 static void TAG(init)( void )
 202 {
 203    tri_tab[IND] = TAG(triangle);
 204    quad_tab[IND] = TAG(quadfunc);
 205 }
 206
 207
 208 #undef IND
 209 #undef TAG