(defmethod uniforms-init ((sphere glfw-sphere-source) (shader-program integer))
  (let ((r (coerce (radius sphere) 'single-float))
	(model-view-matrix (make-instance 'transform-3d))
        (mvm-data (make-array 16)))
    (setf (translate model-view-matrix) (center sphere))
    (setf (scale model-view-matrix) (vector r r r 1))
    (flatten model-view-matrix mvm-data)
    (gl:uniform-matrix
     (gl:get-uniform-location shader-program "ModelMatrix")
     4 (vector mvm-data))))