dll/opengl/glu32/src/libnurbs/nurbtess/gridWrap.cc

   1 /*
   2 ** License Applicability. Except to the extent portions of this file are
   3 ** made subject to an alternative license as permitted in the SGI Free
   4 ** Software License B, Version 1.1 (the "License"), the contents of this
   5 ** file are subject only to the provisions of the License. You may not use
   6 ** this file except in compliance with the License. You may obtain a copy
   7 ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
   8 ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
   9 **
  10 ** http://oss.sgi.com/projects/FreeB
  11 **
  12 ** Note that, as provided in the License, the Software is distributed on an
  13 ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
  14 ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
  15 ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
  16 ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
  17 **
  18 ** Original Code. The Original Code is: OpenGL Sample Implementation,
  19 ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
  20 ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
  21 ** Copyright in any portions created by third parties is as indicated
  22 ** elsewhere herein. All Rights Reserved.
  23 **
  24 ** Additional Notice Provisions: The application programming interfaces
  25 ** established by SGI in conjunction with the Original Code are The
  26 ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
  27 ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
  28 ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
  29 ** Window System(R) (Version 1.3), released October 19, 1998. This software
  30 ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
  31 ** published by SGI, but has not been independently verified as being
  32 ** compliant with the OpenGL(R) version 1.2.1 Specification.
  33 **
  34 */
  35 /*
  36 */
  37
  38 #include "gluos.h"
  39 #include <stdlib.h>
  40 #include <stdio.h>
  41 #include <GL/gl.h>
  42 #include "zlassert.h"
  43 #include "gridWrap.h"
  44
  45
  46 /*******************grid structure****************************/
  47 void gridWrap::print()
  48 {
  49   printf("n_ulines = %i\n", n_ulines);
  50   printf("n_vlines = %i\n", n_vlines);
  51   printf("u_min=%f, umax=%f, vmin=%f, vmax=%f\n", u_min, u_max, v_min, v_max);
  52 }
  53
  54 gridWrap::gridWrap(Int nUlines, Real* uvals,
  55                    Int nVlines, Real* vvals)
  56 {
  57   assert(nUlines>=2);
  58   assert(nVlines>=2);
  59
  60   is_uniform = 0;
  61   n_ulines = nUlines;
  62   n_vlines = nVlines;
  63   u_min = uvals[0];
  64   u_max = uvals[nUlines-1];
  65   v_min = vvals[0];
  66   v_max = vvals[nVlines-1];
  67   u_values = (Real*) malloc(sizeof(Real) * n_ulines);
  68   assert(u_values);
  69   v_values = (Real*) malloc(sizeof(Real) * n_vlines);
  70   assert(v_values);
  71
  72   Int i;
  73   for(i=0; i<n_ulines; i++)
  74     u_values[i] = uvals[i];
  75   for(i=0; i<n_vlines; i++)
  76     v_values[i] = vvals[i];
  77 }
  78
  79 gridWrap::gridWrap(Int nUlines, Int nVlines,
  80                    Real uMin, Real uMax,
  81                    Real vMin, Real vMax
  82                    )
  83 {
  84   is_uniform = 1;
  85   n_ulines = nUlines;
  86   n_vlines = nVlines;
  87   u_min = uMin;
  88   u_max = uMax;
  89   v_min = vMin;
  90   v_max = vMax;
  91   u_values = (Real*) malloc(sizeof(Real) * n_ulines);
  92   assert(u_values);
  93   v_values = (Real*) malloc(sizeof(Real) * n_vlines);
  94   assert(v_values);
  95
  96   Int i;
  97   assert(nUlines>=2);
  98   assert(nVlines>=2);
  99   Real du = (uMax-uMin)/(nUlines-1);
 100   Real dv = (vMax-vMin)/(nVlines-1);
 101
 102   float tempu=uMin;
 103   u_values[0] = tempu;
 104   for(i=1; i<nUlines; i++)
 105     {
 106       tempu += du;
 107       u_values[i] = tempu;
 108     }
 109   u_values[nUlines-1] = uMax;
 110
 111   float tempv=vMin;
 112   v_values[0] = tempv;
 113   for(i=1; i<nVlines; i++)
 114     {
 115       tempv += dv;
 116       v_values[i] = tempv;
 117     }
 118   v_values[nVlines-1] = vMax;
 119 }
 120
 121 gridWrap::~gridWrap()
 122 {
 123   free(u_values);
 124   free(v_values);
 125 }
 126
 127 void gridWrap::draw()
 128 {
 129   int i,j;
 130   glBegin(GL_POINTS);
 131   for(i=0; i<n_ulines; i++)
 132     for(j=0; j<n_vlines; j++)
 133       glVertex2f(get_u_value(i), get_v_value(j));
 134   glEnd();
 135 }
 136
 137 void gridWrap::outputFanWithPoint(Int v, Int uleft, Int uright, Real vert[2], primStream* pStream)
 138 {
 139   Int i;
 140   if(uleft >= uright)
 141     return; //no triangles to output.
 142
 143   pStream->begin();
 144   pStream->insert(vert);
 145
 146   assert(vert[1] != v_values[v]); //don't output degenerate triangles
 147
 148   if(vert[1] > v_values[v]) //vertex is above this grid line: notice the orientation
 149     {
 150       for(i=uleft; i<=uright; i++)
 151         pStream->insert(u_values[i], v_values[v]);
 152     }
 153   else //vertex is below the grid line
 154     {
 155       for(i=uright; i>= uleft; i--)
 156         pStream->insert(u_values[i], v_values[v]);
 157     }
 158
 159   pStream->end(PRIMITIVE_STREAM_FAN);
 160 }
 161
 162
 163
 164 /*each chain stores a number of consecutive
 165  *V-lines within a grid.
 166  *There is one grid vertex on each V-line.
 167  * The total number of V-lines is:
 168  *   nVlines.
 169  * with respect to the grid, the index of the first V-line is
 170  *   firstVlineIndex.
 171  * So with respect to the grid, the index of the ith V-line is
 172  *   firstVlineIndex-i.
 173  * the grid-index of the uline at the ith vline (recall that each vline has one grid point)
 174  * is ulineIndices[i]. The u_value is cached in ulineValues[i], that is,
 175  *   ulineValues[i] = grid->get_u_value(ulineIndices[i])
 176  */
 177 gridBoundaryChain::gridBoundaryChain(
 178                                      gridWrap* gr,
 179                                      Int first_vline_index,
 180                                      Int n_vlines,
 181                                      Int* uline_indices,
 182                                      Int* inner_indices
 183                                      )
 184 : grid(gr), firstVlineIndex(first_vline_index), nVlines(n_vlines)
 185 {
 186   ulineIndices = (Int*) malloc(sizeof(Int) * n_vlines);
 187   assert(ulineIndices);
 188
 189   innerIndices = (Int*) malloc(sizeof(Int) * n_vlines);
 190   assert(innerIndices);
 191
 192   vertices = (Real2*) malloc(sizeof(Real2) * n_vlines);
 193   assert(vertices);
 194
 195
 196
 197   Int i;
 198   for(i=0; i<n_vlines; i++){
 199     ulineIndices[i] = uline_indices[i];
 200     innerIndices[i] = inner_indices[i];
 201   }
 202
 203   for(i=0; i<n_vlines; i++){
 204     vertices[i][0] = gr->get_u_value(ulineIndices[i]);
 205     vertices[i][1] = gr->get_v_value(first_vline_index-i);
 206   }
 207 }
 208
 209 void gridBoundaryChain::draw()
 210 {
 211   Int i;
 212   glBegin(GL_LINE_STRIP);
 213   for(i=0; i<nVlines; i++)
 214     {
 215       glVertex2fv(vertices[i]);
 216     }
 217   glEnd();
 218 }
 219
 220 void gridBoundaryChain::drawInner()
 221 {
 222   Int i;
 223   for(i=1; i<nVlines; i++)
 224     {
 225       glBegin(GL_LINE_STRIP);
 226       glVertex2f(grid->get_u_value(innerIndices[i]), get_v_value(i-1) );
 227       glVertex2f(grid->get_u_value(innerIndices[i]), get_v_value(i) );
 228       glEnd();
 229     }
 230 }
 231
 232 Int gridBoundaryChain::lookfor(Real v, Int i1, Int i2)
 233 {
 234   Int mid;
 235   while(i1 < i2-1)
 236     {
 237       mid = (i1+i2)/2;
 238       if(v > vertices[mid][1])
 239         {
 240           i2 = mid;
 241         }
 242       else
 243         i1 = mid;
 244     }
 245   return i1;
 246 }
 247
 248 /*output the fan of the right end between grid line i-1 and grid line i*/
 249 void gridBoundaryChain::rightEndFan(Int i, primStream* pStream)
 250 {
 251   Int j;
 252   if(getUlineIndex(i) > getUlineIndex(i-1))
 253     {
 254       pStream->begin();
 255       pStream->insert(get_vertex(i-1));
 256       for(j=getUlineIndex(i-1); j<= getUlineIndex(i); j++)
 257         pStream->insert(grid->get_u_value(j), get_v_value(i));
 258       pStream->end(PRIMITIVE_STREAM_FAN);
 259     }
 260   else if(getUlineIndex(i) < getUlineIndex(i-1))
 261     {
 262       pStream->begin();
 263       pStream->insert(get_vertex(i));
 264       for(j=getUlineIndex(i-1); j>= getUlineIndex(i); j--)
 265         pStream->insert(grid->get_u_value(j), get_v_value(i-1));
 266       pStream->end(PRIMITIVE_STREAM_FAN);
 267     }
 268   //otherside, the two are equal, so there is no fan to output
 269 }
 270
 271
 272 /*output the fan of the left end between grid line i-1 and grid line i*/
 273 void gridBoundaryChain::leftEndFan(Int i, primStream* pStream)
 274 {
 275   Int j;
 276   if(getUlineIndex(i) < getUlineIndex(i-1))
 277     {
 278       pStream->begin();
 279       pStream->insert(get_vertex(i-1));
 280       for(j=getUlineIndex(i); j<= getUlineIndex(i-1); j++)
 281         pStream->insert(grid->get_u_value(j), get_v_value(i));
 282       pStream->end(PRIMITIVE_STREAM_FAN);
 283     }
 284   else if(getUlineIndex(i) > getUlineIndex(i-1))
 285     {
 286       pStream->begin();
 287       pStream->insert(get_vertex(i));
 288       for(j=getUlineIndex(i); j>= getUlineIndex(i-1); j--)
 289         pStream->insert(grid->get_u_value(j), get_v_value(i-1));
 290       pStream->end(PRIMITIVE_STREAM_FAN);
 291     }
 292   /*otherwisem, the two are equal, so there is no fan to outout*/
 293 }