Lines Matching +full:max +full:- +full:fingers
4 Multi-touch (MT) Protocol
7 :Copyright: |copy| 2009-2010 Henrik Rydberg <rydberg@euromail.se>
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13 In order to utilize the full power of the new multi-touch and multi-user
16 document describes the multi-touch (MT) protocol which allows kernel
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34 packet. Since these events are ignored by current single-touch (ST)
48 All drivers mark the end of a multi-touch transfer by calling the usual
67 the ABS_MT_TRACKING_ID of the associated slot. A non-negative tracking id
68 is interpreted as a contact, and the value -1 denotes an unused slot. A
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95 Here is what a minimal event sequence for a two-contact touch would look
125 zero-contact event reaching userland.
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131 Here is what a minimal event sequence for a two-contact touch would look
152 ABS_MT_TRACKING_ID -1
162 ABS_MT_TRACKING_ID -1
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186 than unity, is related to the contact pressure. For pressure-based devices,
217 direction of the finger ellipse is given by the vector (a - b).
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255 the notion of pressure. The fingers of the hand and the palm all have
260 of TOUCH and WIDTH for pressure-based devices or any device with a spatial
264 If the resolution is non-zero, the pressure data is in units/gram. See
265 :ref:`input-event-codes` for details.
279 max should be returned; when aligned with the X axis in the negative
280 direction, the range -max should be returned.
283 degree orientation, the reported orientation must exceed the range max to
284 indicate more than a quarter of a revolution. For an upside-down finger,
285 range max * 2 should be returned.
327 the contact. This is a low-level anonymous grouping for type A devices, and
328 should not be confused with the high-level trackingID [#f5]_. Most type A
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351 ABS_MT_TOUCH_MAJOR := max(X, Y)
378 ellipse should align with the vector (T - C), so the diameter must
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393 --------
399 and with ORIENTATION, one can detect twisting of fingers.
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406 in a finger packet must not be recognized as single-touch events.
409 subsequent events of the same type refer to different fingers.
411 .. [#f1] Also, the difference (TOOL_X - POSITION_X) can be used to model tilt.