From 5fc62003752b8ae40ebd95c33c0b5ffe444025e4 Mon Sep 17 00:00:00 2001 From: Jason Gerecke Date: Mon, 19 Jun 2017 15:13:09 -0700 Subject: [PATCH] backends/native: Interpret tablet padding as being input-centric It is possible to interpret the ammount of padding provided to the *_set_tablet_area functions in two different and incompatible ways. The X11 backend effectively treats them as being input-centric (i.e., the padding defines the size of the "dead zone" on the tablet) while the native backend has an output-centric viewpoint (i.e., the padding defines the size of the "dead zone" on the display) viewpoint. This difference in opinion causes the cursor offset to change when switching between Xorg and a Wayland sessions. The calibration utility within g-c-c does its calculations with an input- centric viewpoint, so this patch modifies the native backend to work correctly with these values. To change viewpoints, we can simply invert the scale and negate the offset. It should be noted that this function also forgot to apply scaling to the offsets (as required by the matrix transform done by libinput) which would have further compounded the cursor offset issue under Wayland. https://bugzilla.gnome.org/show_bug.cgi?id=784009 --- src/backends/native/meta-input-settings-native.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/src/backends/native/meta-input-settings-native.c b/src/backends/native/meta-input-settings-native.c index 952625e28..f0d7057fb 100644 --- a/src/backends/native/meta-input-settings-native.c +++ b/src/backends/native/meta-input-settings-native.c @@ -451,8 +451,18 @@ meta_input_settings_native_set_tablet_area (MetaInputSettings *settings, gdouble padding_bottom) { struct libinput_device *libinput_device; - gfloat matrix[6] = { 1. - (padding_left + padding_right), 0., padding_left, - 0., 1. - (padding_top + padding_bottom), padding_top }; + gfloat scale_x; + gfloat scale_y; + gfloat offset_x; + gfloat offset_y; + + scale_x = 1. / (1. - (padding_left + padding_right)); + scale_y = 1. / (1. - (padding_top + padding_bottom)); + offset_x = -padding_left * scale_x; + offset_y = -padding_top * scale_y; + + gfloat matrix[6] = { scale_x, 0., offset_x, + 0., scale_y, offset_y }; libinput_device = clutter_evdev_input_device_get_libinput_device (device); if (!libinput_device ||