diff --git a/OdysseyGameCore.m b/OdysseyGameCore.m
index e1eb110..d184252 100644
--- a/OdysseyGameCore.m
+++ b/OdysseyGameCore.m
@@ -499,6 +499,11 @@ OdysseyGameCore *current;
 
 #pragma mark Video
 
+- (OEIntSize)aspectSize
+{
+    return OEIntSizeMake(EMUWIDTH, EMUHEIGHT);
+}
+
 - (OEIntRect)screenRect
 {
     return OEIntRectMake(0, 0, EMUWIDTH, EMUHEIGHT);