perl-opengl多边形近似球体

bobbai

#!/usr/bin/perl -w
use strict;
use warnings;
use OpenGL qw/ :all /;
use OpenGL::Config;   

glutInit();
glutInitDisplayMode(GLUT_RGB|GLUT_SINGLE);
glutInitWindowPosition(100,100);
glutInitWindowSize(400,400);
glutCreateWindow("my  OpenGL program");
glClearColor(0,0,0,255);
glClear(GL_COLOR_BUFFER_BIT);  
glMatrixMode(GL_PROJECTION);
glOrtho(-2,2,-2,2,-2,2);
glMatrixMode(GL_MODELVIEW);
gluLookAt(0.1,0.1,0.1,0.0,0.0,0.0,0.0,0.1,0.0);
glutDisplayFunc(\&mydis);
glutMainLoop();

sub mydis()
{
my $x;
my $y;
my $z;
my $c=3.1415926/180;
glClearColor(0,0,0,255);
glClear(GL_COLOR_BUFFER_BIT);
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);

for (my $phi=-80.00;$phi<=80.00;$phi+=20.00)
{
my $phir=$c*$phi;
my $phir20=$c*($phi+20);     
glBegin(GL_QUAD_STRIP);      
for (my $theta=-180.00;$theta<=180.00;$theta+=20.00)
{
my $thetar=$c*$theta;
$x=sin($thetar)*cos($phir);
$y=cos($thetar)*cos($phir);
$z=sin($phir);
glVertex3d($x,$y,$z);
$x=sin($thetar)*cos($phir20);
$y=cos($thetar)*cos($phir20);
$z=sin($phir20);         
glVertex3d($x,$y,$z);  
}  
glEnd();  
}
glFlush();
}