src/mesa/swrast_setup/ss_tritmp.h

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  3.5
   4  *
   5  * Copyright (C) 1999  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 <keithw@valinux.com>
  26  */
  27
  28
  29 static void TAG(triangle)(GLcontext *ctx, GLuint e0, GLuint e1, GLuint e2 )
  30 {
  31    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
  32    SWvertex *verts = SWSETUP_CONTEXT(ctx)->verts;
  33    SWvertex *v[3];
  34    GLfloat z[3];
  35    GLfloat offset;
  36    GLenum mode = GL_FILL;
  37    GLuint facing;
  38
  39    v[0] = &verts[e0];
  40    v[1] = &verts[e1];
  41    v[2] = &verts[e2];
  42
  43
  44    if (IND & (SS_TWOSIDE_BIT | SS_OFFSET_BIT | SS_UNFILLED_BIT))
  45    {
  46       GLfloat ex = v[0]->win[0] - v[2]->win[0];
  47       GLfloat ey = v[0]->win[1] - v[2]->win[1];
  48       GLfloat fx = v[1]->win[0] - v[2]->win[0];
  49       GLfloat fy = v[1]->win[1] - v[2]->win[1];
  50       GLfloat cc  = ex*fy - ey*fx;
  51
  52       if (IND & (SS_TWOSIDE_BIT | SS_UNFILLED_BIT))
  53       {
  54          facing = (cc < 0.0) ^ ctx->Polygon._FrontBit;
  55
  56          if (IND & SS_UNFILLED_BIT)
  57             mode = facing ? ctx->Polygon.BackMode : ctx->Polygon.FrontMode;
  58
  59          if (facing == 1) {
  60             if (IND & SS_TWOSIDE_BIT) {
  61                if (IND & SS_RGBA_BIT) {
  62                   GLchan (*vbcolor)[4] = VB->ColorPtr[1]->data;
  63                   GLchan (*vbspec)[4] = VB->SecondaryColorPtr[1]->data;
  64                   SS_COLOR(v[0]->color, vbcolor[e0]);
  65                   SS_COLOR(v[1]->color, vbcolor[e1]);
  66                   SS_COLOR(v[2]->color, vbcolor[e2]);
  67                   SS_SPEC(v[0]->specular, vbspec[e0]);
  68                   SS_SPEC(v[1]->specular, vbspec[e1]);
  69                   SS_SPEC(v[2]->specular, vbspec[e2]);
  70                } else {
  71                   GLuint *vbindex = VB->IndexPtr[1]->data;
  72                   SS_IND(v[0]->index, vbindex[e0]);
  73                   SS_IND(v[1]->index, vbindex[e1]);
  74                   SS_IND(v[2]->index, vbindex[e2]);
  75                }
  76             }
  77          }
  78       }
  79
  80       if (IND & SS_OFFSET_BIT)
  81       {
  82          offset = ctx->Polygon.OffsetUnits;
  83          z[0] = v[0]->win[2];
  84          z[1] = v[1]->win[2];
  85          z[2] = v[2]->win[2];
  86          if (cc * cc > 1e-16) {
  87             GLfloat ez = z[0] - z[2];
  88             GLfloat fz = z[1] - z[2];
  89             GLfloat a = ey*fz - ez*fy;
  90             GLfloat b = ez*fx - ex*fz;
  91             GLfloat ic = 1.0 / cc;
  92             GLfloat ac = a * ic;
  93             GLfloat bc = b * ic;
  94             if (ac < 0.0f) ac = -ac;
  95             if (bc < 0.0f) bc = -bc;
  96             offset += MAX2(ac, bc) * ctx->Polygon.OffsetFactor;
  97          }
  98          offset *= ctx->MRD;
  99          /*printf("offset %g\n", offset);*/
 100       }
 101    }
 102
 103    if (mode == GL_POINT) {
 104       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetPoint) {
 105          v[0]->win[2] += offset;
 106          v[1]->win[2] += offset;
 107          v[2]->win[2] += offset;
 108       }
 109       _swsetup_render_point_tri( ctx, e0, e1, e2 );
 110    } else if (mode == GL_LINE) {
 111       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetLine) {
 112          v[0]->win[2] += offset;
 113          v[1]->win[2] += offset;
 114          v[2]->win[2] += offset;
 115       }
 116       _swsetup_render_line_tri( ctx, e0, e1, e2 );
 117    } else {
 118       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetFill) {
 119          v[0]->win[2] += offset;
 120          v[1]->win[2] += offset;
 121          v[2]->win[2] += offset;
 122       }
 123       _swrast_Triangle( ctx, v[0], v[1], v[2] );
 124    }
 125
 126    if (IND & SS_OFFSET_BIT) {
 127       v[0]->win[2] = z[0];
 128       v[1]->win[2] = z[1];
 129       v[2]->win[2] = z[2];
 130    }
 131
 132    if (IND & SS_TWOSIDE_BIT) {
 133       if (facing == 1) {
 134          if (IND & SS_RGBA_BIT) {
 135             GLchan (*vbcolor)[4] = VB->ColorPtr[0]->data;
 136             GLchan (*vbspec)[4] = VB->SecondaryColorPtr[0]->data;
 137             SS_COLOR(v[0]->color, vbcolor[e0]);
 138             SS_COLOR(v[1]->color, vbcolor[e1]);
 139             SS_COLOR(v[2]->color, vbcolor[e2]);
 140             SS_SPEC(v[0]->specular, vbspec[e0]);
 141             SS_SPEC(v[1]->specular, vbspec[e1]);
 142             SS_SPEC(v[2]->specular, vbspec[e2]);
 143          } else {
 144             GLuint *vbindex = VB->IndexPtr[0]->data;
 145             SS_IND(v[0]->index, vbindex[e0]);
 146             SS_IND(v[1]->index, vbindex[e1]);
 147             SS_IND(v[2]->index, vbindex[e2]);
 148          }
 149       }
 150    }
 151 }
 152
 153
 154
 155 /* Need to do something with edgeflags:
 156  */
 157 static void TAG(quad)( GLcontext *ctx, GLuint v0,
 158                        GLuint v1, GLuint v2, GLuint v3 )
 159 {
 160    if (IND & SS_UNFILLED_BIT) {
 161       struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
 162       GLubyte ef1 = VB->EdgeFlag[v1];
 163       GLubyte ef3 = VB->EdgeFlag[v3];
 164       VB->EdgeFlag[v1] = 0;
 165       TAG(triangle)( ctx, v0, v1, v3 );
 166       VB->EdgeFlag[v1] = ef1;
 167       VB->EdgeFlag[v3] = 0;
 168       TAG(triangle)( ctx, v1, v2, v3 );
 169       VB->EdgeFlag[v3] = ef3;
 170    } else {
 171       TAG(triangle)( ctx, v0, v1, v3 );
 172       TAG(triangle)( ctx, v1, v2, v3 );
 173    }
 174 }
 175
 176
 177
 178
 179 static void TAG(init)( void )
 180 {
 181    tri_tab[IND] = TAG(triangle);
 182    quad_tab[IND] = TAG(quad);
 183 }
 184
 185
 186 #undef IND
 187 #undef TAG
 188
 189
 190