The transition value for the stage of a pressure gesture event of type
- macOS 10.10.3+
This property is specifically intended to provide a value for the transition animation between the stages of a pressure gesture event.
Gesture events of type
NSEvent go through stages, and transitions occur between these stages. This property indicates a transition value between the current stage and the next or prior stage.
This value is distinct from pressure. It immediately resets to
0 as soon as a stage transition occurs. However, this value does not then immediately begin to fluctuate. The value only starts to change as a new stage begins to approach. It then continues to rise or fall throughout the transition, until that new stage is reached.
As pressure increases for the gesture and a new stage approaches, this property provides a value between
1, indicating the approach of the next stage. When pressure is reduced for the gesture and a new stage is approached, this property provides a value between
-1, indicating the approach of the current stage’s release.