diff --git a/core/src/processing/opengl/PGL.java b/core/src/processing/opengl/PGL.java
index 93f7bbe7e..dd47cbfac 100644
--- a/core/src/processing/opengl/PGL.java
+++ b/core/src/processing/opengl/PGL.java
@@ -1943,7 +1943,7 @@ public abstract class PGL {
   }
 
 
-  protected static final String GLSL_ID_REGEX = "(?<![0-9A-Z_a-z])(%s)(?![0-9A-Z_a-z])";
+  protected static final String GLSL_ID_REGEX = "(?<![0-9A-Z_a-z])(%s)(?![0-9A-Z_a-z]|\\s*\\()";
   protected static final String GLSL_FN_REGEX = "(?<![0-9A-Z_a-z])(%s)(?=\\s*\\()";