void FGAPIENTRY glutSolidSierpinskiSponge ( int num_levels, GLdouble offset[3], GLdouble scale )
{
int i, j ;
FREEGLUT_EXIT_IF_NOT_INITIALISED ( "glutSolidSierpinskiSponge" );
if ( num_levels == 0 )
{
glBegin ( GL_TRIANGLES ) ;
for ( i = 0 ; i < NUM_TETR_FACES ; i++ )
{
glNormal3d ( -tet_r[i][0], -tet_r[i][1], -tet_r[i][2] ) ;
for ( j = 0; j < 3; j++ )
{
double x = offset[0] + scale * tet_r[tet_i[i][j]][0] ;
double y = offset[1] + scale * tet_r[tet_i[i][j]][1] ;
double z = offset[2] + scale * tet_r[tet_i[i][j]][2] ;
glVertex3d ( x, y, z ) ;
}
}
glEnd () ;
}
else if ( num_levels > 0 )
{
GLdouble local_offset[3] ; /* Use a local variable to avoid buildup of roundoff errors */
num_levels -- ;
scale /= 2.0 ;
for ( i = 0 ; i < NUM_TETR_FACES ; i++ )
{
local_offset[0] = offset[0] + scale * tet_r[i][0] ;
local_offset[1] = offset[1] + scale * tet_r[i][1] ;
local_offset[2] = offset[2] + scale * tet_r[i][2] ;
glutSolidSierpinskiSponge ( num_levels, local_offset, scale ) ;
}
}
}
static void drawSolidSierpinskiSponge(void) { glutSolidSierpinskiSponge (depth, offset, orad);} /* orad doubles as size input */
static void drawSolidSierpinskiSponge(void)
{ glutSolidSierpinskiSponge (depth, offset, 1); }
