Add Custom Uniforms value update recommendation ShaderMaterial Doc

docs/api/materials/ShaderMaterial.html

@@ -234,6 +234,13 @@
 			</code>
 			</p>
 
+			<p>
+			You're recommended to update custom [page:Uniform] values depending on [page:Object3D object] and [page:Camera camera]
+			in [page:Object3D.onBeforeRender] because [page:Material] can be shared among [page:Mesh mesh], [page:Matrix4 matrixWorld]
+			of [page:Scene] and [page:Camera] are updated in [page:WebGLRenderer.render], and some effects(ex:VREffect) render a [page:Scene scene]
+			with private their own [page:Camera cameras].
+			</p>
+
 		</div>
 
 		<h2>Constructor</h2>