diff --git a/arcade/gl/glsl.py b/arcade/gl/glsl.py
index b8b14f2db..deca02dec 100644
--- a/arcade/gl/glsl.py
+++ b/arcade/gl/glsl.py
@@ -137,8 +137,8 @@ def apply_defines(lines: List[str], defines: Dict[str, str]) -> List[str]:
             if line.startswith("#define"):
                 try:
                     name = line.split()[1]
-                    value = defines.get(name)
-                    if not value:
+                    value = defines.get(name, None)
+                    if value is None:
                         continue
 
                     lines[nr] = "#define {} {}".format(name, str(value))