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    <head>
      <base href="https://bugs.freedesktop.org/">
    </head>
    <body><table border="1" cellspacing="0" cellpadding="8">
        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - extra straight line when drawing with stylus"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=104080">104080</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>extra straight line when drawing with stylus
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>Wayland
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Other
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>All
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>libinput
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>wayland-bugs@lists.freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>carlo@caione.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Hardware is an old Positivo EC10IS1 laptop with a touchscreen on the USB bus:

  ID 22b9:0005 eTurboTouch Technology, Inc.

the bug is the same as <a class="bz_bug_link 
          bz_status_REOPENED "
   title="REOPENED - extra straight line when drawing with stylus"
   href="show_bug.cgi?id=82250">https://bugs.freedesktop.org/show_bug.cgi?id=82250</a>.

That bugzilla entry is not valid anymore since I'm using libinput and not evdev
 but the wrong behaviour is the same (copy and pasting from that story):

<span class="quote">> When using my pen in drawing programs (I tried gimp and mypaint), if draw
> something on the left side (for example), raise the pen from the screen,
> and draw something on e right side, there is a straight line drawn from the
> last point I touched on the left to the first point I touch on the right.</span >

The GDK bug <a href="https://bugzilla.gnome.org/show_bug.cgi?id=735003">https://bugzilla.gnome.org/show_bug.cgi?id=735003</a> is still open but
I'm not sure if it is possible to fix this on the libinput side.

This is the evtest output I get when I touch the touchscreen with the stylus,
draw a line and then raise the pen again:

Event: time 1512412889.394868, type 4 (EV_MSC), code 4 (MSC_SCAN), value d0042 
Event: time 1512412889.394868, type 1 (EV_KEY), code 330 (BTN_TOUCH), value 1
Event: time 1512412889.394868, type 1 (EV_KEY), code 320 (BTN_TOOL_PEN), value
1
Event: time 1512412889.394868, type 3 (EV_ABS), code 0 (ABS_X), value 1328
Event: time 1512412889.394868, type 3 (EV_ABS), code 1 (ABS_Y), value 2941
Event: time 1512412889.394868, -------------- EV_SYN ------------ 
Event: time 1512412889.399326, type 3 (EV_ABS), code 0 (ABS_X), value 1326
Event: time 1512412889.399326, type 3 (EV_ABS), code 1 (ABS_Y), value 2949
Event: time 1512412889.399326, -------------- EV_SYN ------------
Event: time 1512412889.409335, type 3 (EV_ABS), code 0 (ABS_X), value 1325
Event: time 1512412889.409335, type 3 (EV_ABS), code 1 (ABS_Y), value 2963 
Event: time 1512412889.409335, -------------- EV_SYN ------------ 
...
Event: time 1512412889.624330, -------------- EV_SYN ------------ 
Event: time 1512412889.629329, type 3 (EV_ABS), code 0 (ABS_X), value 1871
Event: time 1512412889.629329, type 3 (EV_ABS), code 1 (ABS_Y), value 2399 
Event: time 1512412889.629329, -------------- EV_SYN ------------
Event: time 1512412889.650334, type 4 (EV_MSC), code 4 (MSC_SCAN), value d0042 
Event: time 1512412889.650334, type 1 (EV_KEY), code 330 (BTN_TOUCH), value 0
Event: time 1512412889.650334, type 1 (EV_KEY), code 320 (BTN_TOOL_PEN), value

Event: time 1512412889.650334, -------------- EV_SYN ------------

Some more info on the touchscreen:

P:
/devices/pci0000:00/0000:00:1d.2/usb4/4-2/4-2:1.0/0003:22B9:0005.0001/input/input10/event5 
N: input/event5
S: input/by-id/usb-HID_TOUCH_HID_Touch_Panel-event-mouse
S: input/by-path/pci-0000:00:1d.2-usb-0:2:1.0-event-mouse
E: DEVLINKS=/dev/input/by-path/pci-0000:00:1d.2-usb-0:2:1.0-event-mouse
/dev/input/by-id/usb-HID_TOUCH_HID_Touch_Panel-event-mouse
E: DEVNAME=/dev/input/event5
E:
DEVPATH=/devices/pci0000:00/0000:00:1d.2/usb4/4-2/4-2:1.0/0003:22B9:0005.0001/input/input10/event5
E: ID_BUS=usb
E: ID_INPUT=1
E: ID_INPUT_TOUCHSCREEN=1
E: ID_MODEL=HID_Touch_Panel
E: ID_MODEL_ENC=HID\x20Touch\x20Panel
E: ID_MODEL_ID=0005
E: ID_PATH=pci-0000:00:1d.2-usb-0:2:1.0
E: ID_PATH_TAG=pci-0000_00_1d_2-usb-0_2_1_0
E: ID_REVISION=0000
E: ID_SERIAL=HID_TOUCH_HID_Touch_Panel
E: ID_TYPE=hid
E: ID_USB_DRIVER=usbhid
E: ID_USB_INTERFACES=:030000:
E: ID_USB_INTERFACE_NUM=00
E: ID_VENDOR=HID_TOUCH
E: ID_VENDOR_ENC=HID\x20TOUCH
E: ID_VENDOR_ID=22b9
E: LIBINPUT_DEVICE_GROUP=3/22b9/5/101:usb-0000:00:1d.2-2
E: MAJOR=13
E: MINOR=69
E: SUBSYSTEM=input
E: USEC_INITIALIZED=28633518</pre>
        </div>
      </p>


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