sub image_draw {
        my ( $image,$x,$y,$xsize,$ysize ) = @_;
        glBindTexture(GL_TEXTURE_2D, $image);

        $xmax = $x + $xsize;
        $ymax = $y + $ysize;



        glBegin(GL_QUADS);                                          
        glTexCoord(0.0, 0.0);glVertex($x, $y,  0);
        glTexCoord(1, 0.0); glVertex( $xmax, $y,  0);
        glTexCoord(1, 1); glVertex( $xmax,  $ymax,  0);
        glTexCoord(0.0, 1);glVertex($x,  $ymax,  0);

        glEnd();                                             


}

image_draw($heap->{"images"}->{"2_bgtile"},0,0,640,480);