code: function updateOrtho(modelViewMatrix, cameraProjectionMatrix){
  		// compute transformedUvs
  		var transformedUvs = []
  		originalOrthoVertices.forEach(function(originalOrthoVertices, index){
  			var transformedUv = originalOrthoVertices.clone()
  			// apply modelViewMatrix and projectionMatrix
  			transformedUv.applyMatrix4( modelViewMatrix )
  			transformedUv.applyMatrix4( cameraProjectionMatrix )
  			// apply perspective
  			transformedUv.x /= transformedUv.z
  			transformedUv.y /= transformedUv.z
  			// store it
  			transformedUvs.push(transformedUv)
  		})
  
  		// change orthoMesh vertices
  		for(var i = 0; i < transformedUvs.length; i++){
  			orthoMesh.geometry.vertices[i].copy(transformedUvs[i])
  		}
  		orthoMesh.geometry.computeBoundingSphere()
  		orthoMesh.geometry.verticesNeedUpdate = true
          }
docs: update orthoMesh