Merge: typing: new warning `useless-truism` to catch trainees.

[nit.git] / lib / mnit / input.nit

diff --git a/lib/mnit/input.nit b/lib/mnit/input.nit
index e200d11..e332548 100644 (file)
--- a/lib/mnit/input.nit
+++ b/lib/mnit/input.nit
@@ -41,6 +41,13 @@ interface PointerEvent
 
        # Is this a movement event?
        fun is_move: Bool is abstract
+
+       # Unique identifier of this pointer among other active pointers
+       #
+       # This value is useful to differentiate between pointers (or fingers) on
+       # multi-touch systems. This value does not change for the same pointer
+       # while it touches the screen.
+       fun pointer_id: Int do return 0
 end
 
 # A motion event on screen composed of many `PointerEvent`