diff --git a/Performance-Tips.md b/Performance-Tips.md
index f9398e7..1c788ed 100644
--- a/Performance-Tips.md
+++ b/Performance-Tips.md
@@ -8,6 +8,7 @@ One drawing function like `DrawImage` or `Fill` is usually treated as one (inter
 * All the render targets are same (`A` in `A.DrawImage(B, op)`)
 * All the render sources are same (`B` in `A.DrawImage(B, op)`)
   * This is not a strong request since different images might share a same inner OpenGL texture in high possibility. This is not 100%, so using the same render source is safer.
+* All the `ColorM` are same
 * All the composite modes are same
 * All the filter values are same