Another handy message to have.

Otherwise you get "Uncaught TypeError: Cannot call method 'getInverse' of undefined".

examples/js/renderers/SVGRenderer.js

@@ -83,6 +83,13 @@ THREE.SVGRenderer = function () {
 
 	this.render = function ( scene, camera ) {
 
+		if ( camera instanceof THREE.Camera === false ) {
+
+			console.error( 'THREE.SVGRenderer.render: camera is not an instance of THREE.Camera.' );
+			return;
+
+		}
+
 		var e, el, element, material;
 
 		this.autoClear && this.clear();

src/renderers/CanvasRenderer.js

@@ -175,6 +175,13 @@ THREE.CanvasRenderer = function ( parameters ) {
 
 	this.render = function ( scene, camera ) {
 
+		if ( camera instanceof THREE.Camera === false ) {
+
+			console.error( 'THREE.CanvasRenderer.render: camera is not an instance of THREE.Camera.' );
+			return;
+
+		}
+
 		var e, el, element, material;
 
 		this.autoClear === true ? this.clear() : _context.setTransform( 1, 0, 0, - 1, _canvasWidthHalf, _canvasHeightHalf );

src/renderers/WebGLRenderer.js

@@ -3687,6 +3687,13 @@ THREE.WebGLRenderer = function ( parameters ) {
 
 	this.render = function ( scene, camera, renderTarget, forceClear ) {
 
+		if ( camera instanceof THREE.Camera === false ) {
+
+			console.error( 'THREE.WebGLRenderer.render: camera is not an instance of THREE.Camera.' );
+			return;
+
+		}
+
 		var i, il,
 
 		webglObject, object,