add documentation for webglrenderer.compile

docs/api/renderers/WebGLRenderer.html

@@ -305,6 +305,9 @@
 		This method clears a rendertarget. To do this, it activates the rendertarget.
 		</div>
 
+		<h3>[method:null compile]( [page:Scene scene], [page:Camera camera] )</h3>
+		<div>Compiles all materials in the scene with the camera. This is useful to precompile shaders before the first rendering.</div>
+		
 		<h3>[method:null dispose]( )</h3>
 		<div>Dispose of the current rendering context.</div>