elput: Fix synthetic relative motion events based on abs events

libinput won't actually give us this info, and logs an error instead.
We can't synthesize based on pointer position due to pointer
warping.

So we must track abs reports and use previous abs reports to
synthesize rel events.

1 files changed, 2 insertions, 0 deletions

diff --git a/src/lib/elput/elput_private.h b/src/lib/elput/elput_private.h
index 709871c368..f5bc425182 100644
--- a/src/lib/elput/elput_private.h
+++ b/src/lib/elput/elput_private.h
@@ -231,6 +231,8 @@ struct _Elput_Device
 
    uint32_t ow, oh;
 
+   double absx, absy;
+
    const char *path;
    const char *output_name;
    struct libinput_device *device;