| # input_pipeline > Gestures > Primary Tap Recognizer |
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| Reviewed-on: 2022-07-06 |
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| # Purpose |
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| The tap recognizer detects a one-finger-tap on the touchpad, generates a mouse click event, and discards all touchpad events related to the tap. |
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| A tap occurs when the user puts one-finger down on the touchpad, exercises zero-to-minimal movement of that one finger, and then removes that finger, all within a short time frame and without moving the pad. (This is distinct from a click, for which a user exerts enough force on the touchpad to move the pad itself.) |
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| Notably, this includes discarding any spurious motion that occurs during the tap (when a finger has made contact down but has not yet been raised up). |
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| # State machine |
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| The tap recognizer implements the state machine below. |
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| The state machine is also available in other formats: |
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| - [state machine as graphviz source](primary_tap_state_machine.dot) |
| - [state machine as SVG](primary_tap_state_machine.svg) |
