reactos/lib/glu32/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 ** $Date$ $Revision: 1.1 $
  35 */
  36 /*
  37 ** $Header: /cygdrive/c/RCVS/CVS/ReactOS/reactos/lib/glu32/libnurbs/nurbtess/gridWrap.cc,v 1.1 2004/02/02 16:39:13 navaraf Exp $
  38 */
  39
  40 #include "gluos.h"
  41 #include <stdlib.h>
  42 #include <stdio.h>
  43 #include <GL/gl.h>
  44 #include "zlassert.h"
  45 #include "gridWrap.h"
  46
  47
  48 /*******************grid structure****************************/
  49 void gridWrap::print()
  50 {
  51   printf("n_ulines = %i\n", n_ulines);
  52   printf("n_vlines = %i\n", n_vlines);
  53   printf("u_min=%f, umax=%f, vmin=%f, vmax=%f\n", u_min, u_max, v_min, v_max);
  54 }
  55
  56 gridWrap::gridWrap(Int nUlines, Real* uvals,
  57                    Int nVlines, Real* vvals)
  58 {
  59   assert(nUlines>=2);
  60   assert(nVlines>=2);
  61
  62   is_uniform = 0;
  63   n_ulines = nUlines;
  64   n_vlines = nVlines;
  65   u_min = uvals[0];
  66   u_max = uvals[nUlines-1];
  67   v_min = vvals[0];
  68   v_max = vvals[nVlines-1];
  69   u_values = (Real*) malloc(sizeof(Real) * n_ulines);
  70   assert(u_values);
  71   v_values = (Real*) malloc(sizeof(Real) * n_vlines);
  72   assert(v_values);
  73
  74   Int i;
  75   for(i=0; i<n_ulines; i++)
  76     u_values[i] = uvals[i];
  77   for(i=0; i<n_vlines; i++)
  78     v_values[i] = vvals[i];
  79 }
  80
  81 gridWrap::gridWrap(Int nUlines, Int nVlines,
  82                    Real uMin, Real uMax,
  83                    Real vMin, Real vMax
  84                    )
  85 {
  86   is_uniform = 1;
  87   n_ulines = nUlines;
  88   n_vlines = nVlines;
  89   u_min = uMin;
  90   u_max = uMax;
  91   v_min = vMin;
  92   v_max = vMax;
  93   u_values = (Real*) malloc(sizeof(Real) * n_ulines);
  94   assert(u_values);
  95   v_values = (Real*) malloc(sizeof(Real) * n_vlines);
  96   assert(v_values);
  97
  98   Int i;
  99   assert(nUlines>=2);
 100   assert(nVlines>=2);
 101   Real du = (uMax-uMin)/(nUlines-1);
 102   Real dv = (vMax-vMin)/(nVlines-1);
 103
 104   float tempu=uMin;
 105   u_values[0] = tempu;
 106   for(i=1; i<nUlines; i++)
 107     {
 108       tempu += du;
 109       u_values[i] = tempu;
 110     }
 111   u_values[nUlines-1] = uMax;
 112
 113   float tempv=vMin;
 114   v_values[0] = tempv;
 115   for(i=1; i<nVlines; i++)
 116     {
 117       tempv += dv;
 118       v_values[i] = tempv;
 119     }
 120   v_values[nVlines-1] = vMax;
 121 }
 122
 123 gridWrap::~gridWrap()
 124 {
 125   free(u_values);
 126   free(v_values);
 127 }
 128
 129 void gridWrap::draw()
 130 {
 131   int i,j;
 132   glBegin(GL_POINTS);
 133   for(i=0; i<n_ulines; i++)
 134     for(j=0; j<n_vlines; j++)
 135       glVertex2f(get_u_value(i), get_v_value(j));
 136   glEnd();
 137 }
 138
 139 void gridWrap::outputFanWithPoint(Int v, Int uleft, Int uright, Real vert[2], primStream* pStream)
 140 {
 141   Int i;
 142   if(uleft >= uright)
 143     return; //no triangles to output.
 144
 145   pStream->begin();
 146   pStream->insert(vert);
 147
 148   assert(vert[1] != v_values[v]); //don't output degenerate triangles
 149
 150   if(vert[1] > v_values[v]) //vertex is above this grid line: notice the orientation
 151     {
 152       for(i=uleft; i<=uright; i++)
 153         pStream->insert(u_values[i], v_values[v]);
 154     }
 155   else //vertex is below the grid line
 156     {
 157       for(i=uright; i>= uleft; i--)
 158         pStream->insert(u_values[i], v_values[v]);
 159     }
 160
 161   pStream->end(PRIMITIVE_STREAM_FAN);
 162 }
 163
 164
 165
 166 /*each chain stores a number of consecutive
 167  *V-lines within a grid.
 168  *There is one grid vertex on each V-line.
 169  * The total number of V-lines is:
 170  *   nVlines.
 171  * with respect to the grid, the index of the first V-line is
 172  *   firstVlineIndex.
 173  * So with respect to the grid, the index of the ith V-line is
 174  *   firstVlineIndex-i.
 175  * the grid-index of the uline at the ith vline (recall that each vline has one grid point)
 176  * is ulineIndices[i]. The u_value is cached in ulineValues[i], that is,
 177  *   ulineValues[i] = grid->get_u_value(ulineIndices[i])
 178  */
 179 gridBoundaryChain::gridBoundaryChain(
 180                                      gridWrap* gr,
 181                                      Int first_vline_index,
 182                                      Int n_vlines,
 183                                      Int* uline_indices,
 184                                      Int* inner_indices
 185                                      )
 186 : grid(gr), firstVlineIndex(first_vline_index), nVlines(n_vlines)
 187 {
 188   ulineIndices = (Int*) malloc(sizeof(Int) * n_vlines);
 189   assert(ulineIndices);
 190
 191   innerIndices = (Int*) malloc(sizeof(Int) * n_vlines);
 192   assert(innerIndices);
 193
 194   vertices = (Real2*) malloc(sizeof(Real2) * n_vlines);
 195   assert(vertices);
 196
 197
 198
 199   Int i;
 200   for(i=0; i<n_vlines; i++){
 201     ulineIndices[i] = uline_indices[i];
 202     innerIndices[i] = inner_indices[i];
 203   }
 204
 205   for(i=0; i<n_vlines; i++){
 206     vertices[i][0] = gr->get_u_value(ulineIndices[i]);
 207     vertices[i][1] = gr->get_v_value(first_vline_index-i);
 208   }
 209 }
 210
 211 void gridBoundaryChain::draw()
 212 {
 213   Int i;
 214   glBegin(GL_LINE_STRIP);
 215   for(i=0; i<nVlines; i++)
 216     {
 217       glVertex2fv(vertices[i]);
 218     }
 219   glEnd();
 220 }
 221
 222 void gridBoundaryChain::drawInner()
 223 {
 224   Int i;
 225   for(i=1; i<nVlines; i++)
 226     {
 227       glBegin(GL_LINE_STRIP);
 228       glVertex2f(grid->get_u_value(innerIndices[i]), get_v_value(i-1) );
 229       glVertex2f(grid->get_u_value(innerIndices[i]), get_v_value(i) );
 230       glEnd();
 231     }
 232 }
 233
 234 Int gridBoundaryChain::lookfor(Real v, Int i1, Int i2)
 235 {
 236   Int mid;
 237   while(i1 < i2-1)
 238     {
 239       mid = (i1+i2)/2;
 240       if(v > vertices[mid][1])
 241         {
 242           i2 = mid;
 243         }
 244       else
 245         i1 = mid;
 246     }
 247   return i1;
 248 }
 249
 250 /*output the fan of the right end between grid line i-1 and grid line i*/
 251 void gridBoundaryChain::rightEndFan(Int i, primStream* pStream)
 252 {
 253   Int j;
 254   if(getUlineIndex(i) > getUlineIndex(i-1))
 255     {
 256       pStream->begin();
 257       pStream->insert(get_vertex(i-1));
 258       for(j=getUlineIndex(i-1); j<= getUlineIndex(i); j++)
 259         pStream->insert(grid->get_u_value(j), get_v_value(i));
 260       pStream->end(PRIMITIVE_STREAM_FAN);
 261     }
 262   else if(getUlineIndex(i) < getUlineIndex(i-1))
 263     {
 264       pStream->begin();
 265       pStream->insert(get_vertex(i));
 266       for(j=getUlineIndex(i-1); j>= getUlineIndex(i); j--)
 267         pStream->insert(grid->get_u_value(j), get_v_value(i-1));
 268       pStream->end(PRIMITIVE_STREAM_FAN);
 269     }
 270   //otherside, the two are equal, so there is no fan to output
 271 }
 272
 273
 274 /*output the fan of the left end between grid line i-1 and grid line i*/
 275 void gridBoundaryChain::leftEndFan(Int i, primStream* pStream)
 276 {
 277   Int j;
 278   if(getUlineIndex(i) < getUlineIndex(i-1))
 279     {
 280       pStream->begin();
 281       pStream->insert(get_vertex(i-1));
 282       for(j=getUlineIndex(i); j<= getUlineIndex(i-1); j++)
 283         pStream->insert(grid->get_u_value(j), get_v_value(i));
 284       pStream->end(PRIMITIVE_STREAM_FAN);
 285     }
 286   else if(getUlineIndex(i) > getUlineIndex(i-1))
 287     {
 288       pStream->begin();
 289       pStream->insert(get_vertex(i));
 290       for(j=getUlineIndex(i); j>= getUlineIndex(i-1); j--)
 291         pStream->insert(grid->get_u_value(j), get_v_value(i-1));
 292       pStream->end(PRIMITIVE_STREAM_FAN);
 293     }
 294   /*otherwisem, the two are equal, so there is no fan to outout*/
 295 }