src/glu/mini/nurbscrv.c

   1 /* $Id: nurbscrv.c,v 1.2 2003/08/22 20:11:43 brianp Exp $ */
   2
   3 /*
   4  * Mesa 3-D graphics library
   5  * Version:  3.3
   6  * Copyright (C) 1995-2000  Brian Paul
   7  *
   8  * This library is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Library General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2 of the License, or (at your option) any later version.
  12  *
  13  * This library is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Library General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Library General Public
  19  * License along with this library; if not, write to the Free
  20  * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21  */
  22
  23
  24 /*
  25  * NURBS implementation written by Bogdan Sikorski (bogdan@cira.it)
  26  * See README2 for more info.
  27  */
  28
  29
  30 #ifdef PC_HEADER
  31 #include "all.h"
  32 #else
  33 #include <math.h>
  34 #include <stdlib.h>
  35 #include "gluP.h"
  36 #include "nurbs.h"
  37 #endif
  38
  39
  40
  41 /* main NURBS curve procedure */
  42 void
  43 do_nurbs_curve(GLUnurbsObj * nobj)
  44 {
  45    GLint geom_order, color_order = 0, normal_order = 0, texture_order = 0;
  46    GLenum geom_type;
  47    GLint n_ctrl;
  48    GLfloat *new_geom_ctrl, *new_color_ctrl, *new_normal_ctrl,
  49       *new_texture_ctrl;
  50    GLfloat *geom_ctrl = 0, *color_ctrl = 0, *normal_ctrl = 0, *texture_ctrl = 0;
  51    GLint *factors;
  52    GLint i, j;
  53    GLint geom_dim, color_dim = 0, normal_dim = 0, texture_dim = 0;
  54
  55    /* test the user supplied data */
  56    if (test_nurbs_curves(nobj) != GLU_NO_ERROR)
  57       return;
  58
  59    if (convert_curves(nobj, &new_geom_ctrl, &n_ctrl, &new_color_ctrl,
  60                       &new_normal_ctrl, &new_texture_ctrl) != GLU_NO_ERROR)
  61       return;
  62
  63    geom_order = nobj->curve.geom.order;
  64    geom_type = nobj->curve.geom.type;
  65    geom_dim = nobj->curve.geom.dim;
  66
  67    if (glu_do_sampling_crv(nobj, new_geom_ctrl, n_ctrl, geom_order, geom_dim,
  68                            &factors) != GLU_NO_ERROR) {
  69       free(new_geom_ctrl);
  70       if (new_color_ctrl)
  71          free(new_color_ctrl);
  72       if (new_normal_ctrl)
  73          free(new_normal_ctrl);
  74       if (new_texture_ctrl)
  75          free(new_texture_ctrl);
  76       return;
  77    }
  78    glEnable(geom_type);
  79    if (new_color_ctrl) {
  80       glEnable(nobj->curve.color.type);
  81       color_dim = nobj->curve.color.dim;
  82       color_ctrl = new_color_ctrl;
  83       color_order = nobj->curve.color.order;
  84    }
  85    if (new_normal_ctrl) {
  86       glEnable(nobj->curve.normal.type);
  87       normal_dim = nobj->curve.normal.dim;
  88       normal_ctrl = new_normal_ctrl;
  89       normal_order = nobj->curve.normal.order;
  90    }
  91    if (new_texture_ctrl) {
  92       glEnable(nobj->curve.texture.type);
  93       texture_dim = nobj->curve.texture.dim;
  94       texture_ctrl = new_texture_ctrl;
  95       texture_order = nobj->curve.texture.order;
  96    }
  97    for (i = 0, j = 0, geom_ctrl = new_geom_ctrl;
  98         i < n_ctrl; i += geom_order, j++, geom_ctrl += geom_order * geom_dim) {
  99       if (fine_culling_test_2D
 100           (nobj, geom_ctrl, geom_order, geom_dim, geom_dim)) {
 101          color_ctrl += color_order * color_dim;
 102          normal_ctrl += normal_order * normal_dim;
 103          texture_ctrl += texture_order * texture_dim;
 104          continue;
 105       }
 106       glMap1f(geom_type, 0.0, 1.0, geom_dim, geom_order, geom_ctrl);
 107       if (new_color_ctrl) {
 108          glMap1f(nobj->curve.color.type, 0.0, 1.0, color_dim,
 109                  color_order, color_ctrl);
 110          color_ctrl += color_order * color_dim;
 111       }
 112       if (new_normal_ctrl) {
 113          glMap1f(nobj->curve.normal.type, 0.0, 1.0, normal_dim,
 114                  normal_order, normal_ctrl);
 115          normal_ctrl += normal_order * normal_dim;
 116       }
 117       if (new_texture_ctrl) {
 118          glMap1f(nobj->curve.texture.type, 0.0, 1.0, texture_dim,
 119                  texture_order, texture_ctrl);
 120          texture_ctrl += texture_order * texture_dim;
 121       }
 122       glMapGrid1f(factors[j], 0.0, 1.0);
 123       glEvalMesh1(GL_LINE, 0, factors[j]);
 124    }
 125    free(new_geom_ctrl);
 126    free(factors);
 127    if (new_color_ctrl)
 128       free(new_color_ctrl);
 129    if (new_normal_ctrl)
 130       free(new_normal_ctrl);
 131    if (new_texture_ctrl)
 132       free(new_texture_ctrl);
 133 }