<HTML><HEAD> <META content=IE=5 http-equiv=X-UA-Compatible> <META content="text/html; charset=utf-8" http-equiv=Content-Type> <STYLE id=mysingle_style type=text/css>.search-word { BACKGROUND-COLOR: #ffee94 } P { FONT-SIZE: 10pt; MARGIN-BOTTOM: 5px; FONT-FAMILY: 맑은 고딕, arial; MARGIN-TOP: 5px } TD { FONT-SIZE: 10pt; MARGIN-BOTTOM: 5px; FONT-FAMILY: 맑은 고딕, arial; MARGIN-TOP: 5px } LI { FONT-SIZE: 10pt; MARGIN-BOTTOM: 5px; FONT-FAMILY: 맑은 고딕, arial; MARGIN-TOP: 5px } BODY { FONT-SIZE: 10pt; FONT-FAMILY: 맑은 고딕, arial; MARGIN: 10px; LINE-HEIGHT: 1.4 } </STYLE> <STYLE id=knox_style type=text/css>P { FONT-SIZE: 10pt; MARGIN-BOTTOM: 5px; FONT-FAMILY: 맑은 고딕, arial; MARGIN-TOP: 5px } </STYLE> <META name=GENERATOR content=ActiveSquare></HEAD> <BODY style="OVERFLOW: auto"> Dear Mr. Hutterer. Thanks you for your reply. And I have another question about this, so I hope you reply about this question. Following my second case, libinput reports below events. (used evtest and libinput debug-events) <TABLE style="WIDTH: 818px; BACKGROUND-COLOR: #ffffff" cellSpacing=0 cellPadding=0 width=818 border=1> <TBODY> <TR> <TD height=20 width=818> Event: time 1420073073.110197, type 3 (Absolute), code 57 (MT Tracking ID), value 22 Event: time 1420073073.110197, type 1 (Key), code 330 (Touch), value 1 Event: time 1420073073.110197, type 3 (Absolute), code 53 (MT Position X), value 176 Event: time 1420073073.110197, type 3 (Absolute), code 54 (MT Position Y), value 1027 Event: time 1420073073.143950, -------------- Report Sync ------------ Event: time 1420073073.165862, type 3 (Absolute), code 57 (MT Tracking ID), value -1 Event: time 1420073073.165862, type 1 (Key), code 330 (Touch), value 0 Event: time 1420073073.165862, type 3 (Absolute), code 47 (MT Slot), value 1 Event: time 1420073073.165862, type 3 (Absolute), code 57 (MT Tracking ID), value 23 Event: time 1420073073.165862, type 1 (Key), code 330 (Touch), value 1 Event: time 1420073073.165862, type 3 (Absolute), code 53 (MT Position X), value 628 Event: time 1420073073.165862, type 3 (Absolute), code 54 (MT Position Y), value 1099 Event: time 1420073073.177031, -------------- Report Sync ------------ Event: time 1420073073.210082, type 3 (Absolute), code 57 (MT Tracking ID), value -1 Event: time 1420073073.210082, type 1 (Key), code 330 (Touch), value 0 Event: time 1420073073.210082, -------------- Report Sync ------------</TD></TR></TBODY></TABLE> <TABLE style="WIDTH: 818px; BACKGROUND-COLOR: #ffffff" cellSpacing=0 cellPadding=0 width=818 border=1> <TBODY> <TR> <TD height=20 width=818> event2 TOUCH_DOWN +39.022s 0 (0) 24.44/80.23 (176.00/1027.00mm) event2 TOUCH_FRAME +39.022s event2 TOUCH_UP +39.078s event2 TOUCH_DOWN +39.078s 1 (0) 87.22/85.86 (628.00/1099.00mm) event2 TOUCH_FRAME +39.078s event2 TOUCH_UP +39.122s event2 TOUCH_FRAME +39.122s</TD></TR></TBODY></TABLE> So I looks like 1st finger down -> 1st finger up -> 2nd finger down -> 2nd finger up I interpret it: 2nd finger down can come first than 1st finger, after all fingers are released. I have thought that first touch down's index is always 0. But following in this case, second or third touch down can come fater than first touch down. So I ask it to you that second finger down came fisrt situation is normal situation or not.. I'll waiting for your reply. If you reply about this, it helps me a lot. Thanks and regards, JeongHyun Kang. --------- Original Message --------- Sender : Peter Hutterer <peter.hutterer@who-t.net> Date : 2020-05-22 12:32 (GMT+9) Title : Re: Question about Linux MT Protocol B type <PRE>On Thu, May 21, 2020 at 07:42:33PM +0900, 강정현 wrote: > Dear all, > > I have an one question about Linux MT Protocol B type. > > Asume that press touch screen using first finger. > > And release fisrt finger and press second finger toghether. > > > > In that case, which procotol is correct? > > ┌───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐ > │ ABS_MT_SLOT 0 │ > │ │ > │ ABS_MT_TRACKING_ID 1 │ > │ │ > │ ABS_MT_POSITION_X 10 │ > │ │ > │ ABS_MT_POSITION_Y 5 │ > │ │ > │ ABS_MT_SYNC <-- first finger press │ > └───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘ There's no such thing as ABS_MT_SYNC, use SYN_REPORT here. > first case > > ┌───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐ > │ ABS_MT_TRACKING_ID -1 │ > │ │ > │ ABS_MT_TRACKING_ID 2 │ > │ │ > │ ABS_MT_POSITION_X 15 │ > │ │ > │ ABS_MT_POSITION_Y 10 │ > │ │ > │ ABS_MT_SYNC <-- first finger release and first finger press is generated │ > └───────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘ Nope, that's wrong. You could skip the tracking ID -1 event and switch directly to ID 2. This is technically allowed by the protocol but a lot of userspace (anything Xorg and libinput) will struggle with it for historical reasons. Where you are re-using the same slot, you should always stop a touch and start the next touch in a separate frame. Direct switching also introduces some ambiguity because it merely means "kernel lost tracking of touch point", so userspace now has to decide whether it's the same touch or a new touch. > > second case > > ┌────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐ > │ ABS_MT_TRACKING_ID -1 │ > │ │ > │ ABS_MT_SLOT 1 │ > │ │ > │ ABS_MT_TRACKING_ID 2 │ > │ │ > │ ABS_MT_POSITION_X 15 │ > │ │ > │ ABS_MT_POSITION_Y 10 │ > │ │ > │ ABS_MT_SYNC <-- first finger release and second finger press is generated │ > └────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘ this is the correct sequence (except for the ABS_MT_SYNC bit :). Cheers, Peter _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org https://protect2.fireeye.com/url?k=b0d106c4-ed1dcf40-b0d08d8b-0cc47aa8f5ba-4eb0ded9c4a94a0e&q=1&u=https%3A%2F%2Flists.freedesktop.org%2Fmailman%2Flistinfo%2Fwayland-devel </PRE><table id=bannersignimg data-cui-lock="true" namo_lock><tr><td> </td></tr></table><table id=confidentialsignimg data-cui-lock="true" namo_lock><tr><td><img style="border: 0px solid currentColor; border-image: none; width: 520px; height: 144px; display: inline-block;" unselectable="on" data-cui-image="true" src="cid:cafe_image_0@s-core.co.kr"> </td></tr></table></BODY></HTML><img src='http://ext.samsung.net/mail/ext/v1/external/status/update?userid=jhyuni.kang&do=bWFpbElEPTIwMjAwNTIyMDg0NDA5ZXBjbXMxcDhiMmQ1MzcwMWZkMDI3NTU0MTUwMzM3OTM1OGM2NTIxMSZyZWNpcGllbnRBZGRyZXNzPXdheWxhbmQtZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3Jn' border=0 width=0 height=0 style='display:none'>