Hi Frank,
If you want to use the space-bar to fire the LASER, use key[32].
Float colors go from 0.0 to 1.0, so this one is a green translucent laser, (firing along the z axis)
if key[32]
glLineWidth 4.0
glBegin GL_LINES
glColor4f 0.0 ,1.0, 0.0, 0.50
glVertex3f 0.0, 0.0, 0.0
glVertex3f 0.0, 0.0, -8.0
glEnd
end if
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