diff --git a/Defining-custom-shaders.md b/Defining-custom-shaders.md
index 3d5e7cc..dc6bd8d 100644
--- a/Defining-custom-shaders.md
+++ b/Defining-custom-shaders.md
@@ -73,6 +73,7 @@ An example of a typical topological shader configuration is shown below:
         color0: "#696969"
         linecolor: "#000000"
         watercolor: "#0000FF"
+        hiddenids: [ 0 ]
 
 The settings for the TopoHDShader include: