dll/opengl/mesa/swrast_setup/ss_tritmp.h

   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  */
  33 static void TAG(triangle)(struct gl_context *ctx, GLuint e0, GLuint e1, GLuint e2 )
  34 {
  35 #if IND & SS_TWOSIDE_BIT
  36    struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
  37    SScontext *swsetup = SWSETUP_CONTEXT(ctx);
  38    GLchan saved_color[3][4] = { { 0 } };
  39    GLfloat saved_col0[3][4] = { { 0 } };
  40 #endif
  41    SWvertex *verts = SWSETUP_CONTEXT(ctx)->verts;
  42    SWvertex *v[3];
  43 #if IND & SS_OFFSET_BIT
  44    GLfloat z[3];
  45 #endif
  46    GLfloat oz0, oz1, oz2;
  47    GLenum mode = GL_FILL;
  48    GLuint facing = 0;
  49
  50    v[0] = &verts[e0];
  51    v[1] = &verts[e1];
  52    v[2] = &verts[e2];
  53
  54 #if IND & (SS_TWOSIDE_BIT | SS_OFFSET_BIT | SS_UNFILLED_BIT)
  55    {
  56       GLfloat ex = v[0]->attrib[FRAG_ATTRIB_WPOS][0] - v[2]->attrib[FRAG_ATTRIB_WPOS][0];
  57       GLfloat ey = v[0]->attrib[FRAG_ATTRIB_WPOS][1] - v[2]->attrib[FRAG_ATTRIB_WPOS][1];
  58       GLfloat fx = v[1]->attrib[FRAG_ATTRIB_WPOS][0] - v[2]->attrib[FRAG_ATTRIB_WPOS][0];
  59       GLfloat fy = v[1]->attrib[FRAG_ATTRIB_WPOS][1] - v[2]->attrib[FRAG_ATTRIB_WPOS][1];
  60       GLfloat cc  = ex*fy - ey*fx;
  61
  62 #if IND & (SS_TWOSIDE_BIT | SS_UNFILLED_BIT)
  63       {
  64          facing = (cc < 0.0) ^ ctx->Polygon._FrontBit;
  65
  66 #if IND & SS_UNFILLED_BIT
  67             mode = facing ? ctx->Polygon.BackMode : ctx->Polygon.FrontMode;
  68 #endif
  69
  70 #if IND & SS_TWOSIDE_BIT
  71          if (facing == 1) {
  72                if (VB->BackfaceColorPtr) {
  73                   GLfloat (*vbcolor)[4] = VB->BackfaceColorPtr->data;
  74
  75                   if (swsetup->intColors) {
  76                      COPY_CHAN4(saved_color[0], v[0]->color);
  77                      COPY_CHAN4(saved_color[1], v[1]->color);
  78                      COPY_CHAN4(saved_color[2], v[2]->color);
  79                   }
  80                   else {
  81                      COPY_4V(saved_col0[0], v[0]->attrib[FRAG_ATTRIB_COL]);
  82                      COPY_4V(saved_col0[1], v[1]->attrib[FRAG_ATTRIB_COL]);
  83                      COPY_4V(saved_col0[2], v[2]->attrib[FRAG_ATTRIB_COL]);
  84                   }
  85
  86                   if (VB->BackfaceColorPtr->stride) {
  87                      if (swsetup->intColors) {
  88                         SS_COLOR(v[0]->color, vbcolor[e0]);
  89                         SS_COLOR(v[1]->color, vbcolor[e1]);
  90                         SS_COLOR(v[2]->color, vbcolor[e2]);
  91                      }
  92                      else {
  93                         COPY_4V(v[0]->attrib[FRAG_ATTRIB_COL], vbcolor[e0]);
  94                         COPY_4V(v[1]->attrib[FRAG_ATTRIB_COL], vbcolor[e1]);
  95                         COPY_4V(v[2]->attrib[FRAG_ATTRIB_COL], vbcolor[e2]);
  96                      }
  97                   }
  98                   else {
  99                      /* flat shade */
 100                      if (swsetup->intColors) {
 101                         SS_COLOR(v[0]->color, vbcolor[0]);
 102                         SS_COLOR(v[1]->color, vbcolor[0]);
 103                         SS_COLOR(v[2]->color, vbcolor[0]);
 104                      }
 105                      else {
 106                         COPY_4V(v[0]->attrib[FRAG_ATTRIB_COL], vbcolor[0]);
 107                         COPY_4V(v[1]->attrib[FRAG_ATTRIB_COL], vbcolor[0]);
 108                         COPY_4V(v[2]->attrib[FRAG_ATTRIB_COL], vbcolor[0]);
 109                      }
 110                   }
 111                }
 112             }
 113 #endif
 114       }
 115 #endif
 116
 117 #if IND & SS_OFFSET_BIT
 118       {
 119          GLfloat offset;
 120          const GLfloat max = ctx->DrawBuffer->_DepthMaxF;
 121          /* save original Z values (restored later) */
 122          z[0] = v[0]->attrib[FRAG_ATTRIB_WPOS][2];
 123          z[1] = v[1]->attrib[FRAG_ATTRIB_WPOS][2];
 124          z[2] = v[2]->attrib[FRAG_ATTRIB_WPOS][2];
 125          /* Note that Z values are already scaled to [0,65535] (for example)
 126           * so no MRD value is used here.
 127           */
 128          offset = ctx->Polygon.OffsetUnits;
 129          if (cc * cc > 1e-16) {
 130             const GLfloat ez = z[0] - z[2];
 131             const GLfloat fz = z[1] - z[2];
 132             const GLfloat oneOverArea = 1.0F / cc;
 133             const GLfloat dzdx = FABSF((ey * fz - ez * fy) * oneOverArea);
 134             const GLfloat dzdy = FABSF((ez * fx - ex * fz) * oneOverArea);
 135             offset += MAX2(dzdx, dzdy) * ctx->Polygon.OffsetFactor;
 136          }
 137          /* new Z values */
 138          oz0 = CLAMP(v[0]->attrib[FRAG_ATTRIB_WPOS][2] + offset, 0.0F, max);
 139          oz1 = CLAMP(v[1]->attrib[FRAG_ATTRIB_WPOS][2] + offset, 0.0F, max);
 140          oz2 = CLAMP(v[2]->attrib[FRAG_ATTRIB_WPOS][2] + offset, 0.0F, max);
 141       }
 142 #endif
 143    }
 144 #endif
 145
 146    if (mode == GL_POINT) {
 147       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetPoint) {
 148          v[0]->attrib[FRAG_ATTRIB_WPOS][2] = oz0;
 149          v[1]->attrib[FRAG_ATTRIB_WPOS][2] = oz1;
 150          v[2]->attrib[FRAG_ATTRIB_WPOS][2] = oz2;
 151       }
 152       _swsetup_render_tri(ctx, e0, e1, e2, facing, _swsetup_edge_render_point_tri);
 153    } else if (mode == GL_LINE) {
 154       if ((IND & SS_OFFSET_BIT) && ctx->Polygon.OffsetLine) {
 155          v[0]->attrib[FRAG_ATTRIB_WPOS][2] = oz0;
 156          v[1]->attrib[FRAG_ATTRIB_WPOS][2] = oz1;
 157          v[2]->attrib[FRAG_ATTRIB_WPOS][2] = oz2;
 158       }
 159       _swsetup_render_tri(ctx, e0, e1, e2, facing, _swsetup_edge_render_line_tri);
 160    }
 161    else {
 162 #if IND & SS_OFFSET_BIT
 163       if (ctx->Polygon.OffsetFill) {
 164          v[0]->attrib[FRAG_ATTRIB_WPOS][2] = oz0;
 165          v[1]->attrib[FRAG_ATTRIB_WPOS][2] = oz1;
 166          v[2]->attrib[FRAG_ATTRIB_WPOS][2] = oz2;
 167       }
 168 #endif
 169       _swrast_Triangle( ctx, v[0], v[1], v[2] );
 170    }
 171
 172    /*
 173     * Restore original vertex colors, etc.
 174     */
 175 #if IND & SS_OFFSET_BIT
 176    {
 177       v[0]->attrib[FRAG_ATTRIB_WPOS][2] = z[0];
 178       v[1]->attrib[FRAG_ATTRIB_WPOS][2] = z[1];
 179       v[2]->attrib[FRAG_ATTRIB_WPOS][2] = z[2];
 180    }
 181 #endif
 182
 183 #if IND & SS_TWOSIDE_BIT
 184    {
 185       if (facing == 1) {
 186         if (VB->BackfaceColorPtr) {
 187           if (swsetup->intColors) {
 188             COPY_CHAN4(v[0]->color, saved_color[0]);
 189             COPY_CHAN4(v[1]->color, saved_color[1]);
 190             COPY_CHAN4(v[2]->color, saved_color[2]);
 191           }
 192           else {
 193             COPY_4V(v[0]->attrib[FRAG_ATTRIB_COL], saved_col0[0]);
 194             COPY_4V(v[1]->attrib[FRAG_ATTRIB_COL], saved_col0[1]);
 195             COPY_4V(v[2]->attrib[FRAG_ATTRIB_COL], saved_col0[2]);
 196           }
 197         }
 198       }
 199    }
 200 #endif
 201 }
 202
 203
 204
 205 /* Need to fixup edgeflags when decomposing to triangles:
 206  */
 207 static void TAG(quadfunc)( struct gl_context *ctx, GLuint v0,
 208                        GLuint v1, GLuint v2, GLuint v3 )
 209 {
 210    if (IND & SS_UNFILLED_BIT) {
 211       struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
 212       if (VB->EdgeFlag) { /* XXX this test shouldn't be needed (bug 12614) */
 213          GLubyte ef1 = VB->EdgeFlag[v1];
 214          GLubyte ef3 = VB->EdgeFlag[v3];
 215          VB->EdgeFlag[v1] = 0;
 216          TAG(triangle)( ctx, v0, v1, v3 );
 217          VB->EdgeFlag[v1] = ef1;
 218          VB->EdgeFlag[v3] = 0;
 219          TAG(triangle)( ctx, v1, v2, v3 );
 220          VB->EdgeFlag[v3] = ef3;
 221       }
 222    } else {
 223       TAG(triangle)( ctx, v0, v1, v3 );
 224       TAG(triangle)( ctx, v1, v2, v3 );
 225    }
 226 }
 227
 228
 229
 230
 231 static void TAG(init)( void )
 232 {
 233    tri_tab[IND] = TAG(triangle);
 234    quad_tab[IND] = TAG(quadfunc);
 235 }
 236
 237
 238 #undef IND
 239 #undef TAG