Jonas Dreßler 63cc4da4f9 clutter/gesture: Cancel other gestures when moving to RECOGNIZING ... Quite often there are situations where multiple gestures try to recognize, keeping track of the same set of points (for example an edge drag gesture on the stage and a click gesture somewhere in the scenegraph). Usually what's wanted here is that the first gesture to move to RECOGNIZING wins over all other active gestures and "claims" the point for itself. We implement this by introducing a concept called "influencing". It works by making all gestures operating on a shared set of points aware of each other using ClutterAction->register_sequence(). ClutterGesture uses this vfunc to keep track of all other ClutterGestures that are potentially conflicting, and keeps a list (priv->cancel_on_recognizing) of those. As soon as the move to RECOGNIZING happens, all gestures inside this list get moved to CANCELLED. To allow fine-grained control over this behavior, two APIs are introduced: 1) on the implementation level (should_influence() and should_be_influenced_by()): This is a vfunc that gets called as soon as a potential conflict is detected. It's helpful when a specific gesture always behaves the same towards another gesture, for example to make sure a LongPress gesture never cancels a DragGesture. 2) on the gesture user level, clutter_gesture_can_not_cancel() is introduced: This allows control for the user of a gesture to specify that a specific instance of a gesture won't cancel another gesture. Calling this twice so that both gestures can't cancel each other allows for things like simultaneous recognition of a pinch-to-zoom and rotate gesture. Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2389>		2024-03-15 00:07:59 +01:00
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clutter	clutter/gesture: Cancel other gestures when moving to RECOGNIZING	2024-03-15 00:07:59 +01:00
meson.build	clutter: Explicitly depend on cairo	2024-01-27 10:03:15 +00:00