sphere.c

   1 /**
   2  * @file sphere.c
   3  * @brief The snowball module.
   4  *
   5  * Copyright 2001, 2008 David Ashley  <dashxdr@gmail.com>
   6  * Copyright 2008 Stephen M. Webb  <stephen.webb@bregmasoft.ca>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of Version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  */
  21 #include "sphere.h"
  22
  23 #if defined(_WIN32) && !defined(__CYGWIN__)
  24 # define WIN32_LEAN_AND_MEAN 1
  25 # include <windows.h>
  26 #endif
  27
  28 #include <GL/gl.h>
  29 #include <math.h>
  30 #include "misc.h"
  31
  32
  33 void makeuvsphere(float size)
  34 {
  35 #define USIDES 15
  36 #define VSIDES 9
  37 float x[USIDES],z[USIDES];
  38 int i,j,t,o;
  39 float a;
  40 float c1,s1,c2,s2;
  41         for(i=0;i<USIDES;++i)
  42         {
  43                 a=i*PI*2.0f/USIDES;
  44                 x[i]=cosf(a)*size;
  45                 z[i]=sinf(a)*size;
  46         }
  47
  48         glEnable(GL_NORMALIZE);
  49
  50         for(i=0;i<VSIDES;++i)
  51         {
  52                 a=i*PI/VSIDES;
  53                 c1=cosf(a);
  54                 s1=sinf(a);
  55                 a=(i+1)*PI/VSIDES;
  56                 c2=cosf(a);
  57                 s2=sinf(a);
  58                 glBegin(GL_QUAD_STRIP);
  59                 for(j=0;j<USIDES+1;++j)
  60                 {
  61                         t=(j<USIDES) ? j : j-USIDES;
  62                         if(j)
  63                         {
  64                                 float s,c;
  65                                 a=(i+0.5f)*PI/VSIDES;
  66                                 c=cosf(a);
  67                                 s=sinf(a);
  68                                 a=(j-0.5f)*PI*2.0f/USIDES;
  69                                 glNormal3f(cosf(a)*s,c,sinf(a)*s);
  70                         }
  71                         glVertex3f(x[t]*s2,c2*size,z[t]*s2);
  72                         glVertex3f(x[t]*s1,c1*size,z[t]*s1);
  73                         o=t;
  74                 }
  75                 glEnd();
  76         }
  77 }
  78
  79