object callbacks (#9738)

* object callbacks

per previous request

added after call
added arguments to both calls

* faster function evaluation, missing comma

src/core/Object3D.js

@@ -91,7 +91,8 @@ function Object3D() {
 
 	this.userData = {};
 
-	this.onBeforeRender = null;
+	this.onBeforeRender = function(){}; 
+	this.onAfterRender = function(){};
 
 }
 

src/renderers/WebGLRenderer.js

@@ -1525,12 +1525,15 @@ function WebGLRenderer( parameters ) {
 
 			} else {
 
-				if ( object.onBeforeRender !== null ) object.onBeforeRender();
+				object.onBeforeRender( _this , _gl , camera, fog, geometry, material, object, group );
 
 				_this.renderBufferDirect( camera, fog, geometry, material, object, group );
 
 			}
 
+			object.onAfterRender( _this , _gl , camera, fog, geometry, material, object, group );
+
+
 		}
 
 	}