diff --git a/java/libraries/opengl/examples/Lights/Directional/Directional.pde b/java/libraries/opengl/examples/Lights/Directional/Directional.pde
index d3f401db0..f88e61f4f 100755
--- a/java/libraries/opengl/examples/Lights/Directional/Directional.pde
+++ b/java/libraries/opengl/examples/Lights/Directional/Directional.pde
@@ -19,7 +19,7 @@ void draw() {
   background(0); 
   float dirY = (mouseY / float(height) - 0.5) * 2;
   float dirX = (mouseX / float(width) - 0.5) * 2;
-  directionalLight(204, 204, 204, dirX, dirY, -1);
+  directionalLight(204, 204, 204, -dirX, -dirY, -1);
   translate(width/2 - 100, height/2, 0); 
   sphere(80); 
   translate(200, 0, 0);