proc kugel {radius} {
    set kante 10
    set ::displayliste [glGenLists 1]
    glNewList $::displayliste GL_COMPILE
    for {set l 0} {$l <= 360} {incr l 5} {
	for {set b -90 } {$b <= 90} {incr b 5} {
	    # Position im Bogenmaß
	    set lr [expr {$l/180.0 * $::PI}]
	    set br [expr {$b/180.0 * $::PI}]
		   
	    # Farbe für das nächste Element setzen
	    set hue [expr {sin($br/3.0)}]
	    eval glColor3f [hls2rgb $hue 1 1]

	    # Dreieck einfügen
	    glBegin GL_TRIANGLES
	    glVertex3f [expr {$radius * cos($lr) * cos($br)}] \
		[expr {$radius * sin($lr) * cos($br)}] \
		[expr {$radius * sin($br)}]
	    glVertex3f [expr {$radius * cos($lr) * cos($br)}] \
		[expr {$radius * sin($lr) * cos($br) +$kante}] \
		[expr {$radius * sin($br)}]
	    glVertex3f [expr {$radius * cos($lr) * cos($br)}] \
		[expr {$radius * sin($lr) * cos($br)}] \
		[expr {$radius * sin($br) +$kante}]
	    glEnd 
	}
    }
    glEndList
}