#!/usr/local/bin/perl 
#
# This is an example of combining the tk module and opengl
# You have to have TK installed for this to work.
# this program opens a window and when you hit a key in
# the window a callback that does some opengl stuff is
# executed.  
# Yes, this is a totally lame program, but its a proof
# of concept sort of thing.
# We'll get something better next time :-)
#

use lib ('blib');
use Tk;
use OpenGL;

$top = MainWindow->new();

sub DoKey
{
	$w = shift;
	$id = $w->WindowId;
	#print " window id: $id -> ",$$id,"\n";
	glpOpenWindow(width=>50,height=>50,parent=>$$id);
	glClearColor(0,0,1,1);
	glClear(GL_COLOR_BUFFER_BIT);
	glOrtho(-1,1,-1,1,-1,1);
	
	glColor3f(1,0,0);
	glBegin(GL_POLYGON);
	  glVertex2f(-0.5,-0.5);
	  glVertex2f(-0.5, 0.5);
	  glVertex2f( 0.5, 0.5);
	  glVertex2f( 0.5,-0.5);
	glEnd();
	glFlush();
}

$top->bind("<Any-KeyPress>",\&DoKey);

Tk::MainLoop();