Compute the swipe distance from the physical dpi

The previous computation was very different depending on the device's
screen and accessibility options.
Given that the keyboard is supposed to fill all the space in one
dimension, the dpi unit makes little sense.

The formula doesn't mean anything in particular, it takes into account
both dimensions (x and y) and should be close to the dpi in the
diagonals (which is the direction of swipe).

This changes the actual value, on a 1920x1080 480dpi screen, the value
is increased by 20%.

1 files changed, 5 insertions, 3 deletions

diff --git a/srcs/juloo.keyboard2/Config.java b/srcs/juloo.keyboard2/Config.java
index aa583de..76aa4e0 100644
--- a/srcs/juloo.keyboard2/Config.java
+++ b/srcs/juloo.keyboard2/Config.java
@@ -23,7 +23,6 @@ final class Config
 
   // From preferences
   public int layout; // Or '-1' for the system defaults
-  private float swipe_dist_dp;
   public float swipe_dist_px;
   public boolean vibrateEnabled;
   public long vibrateDuration;
@@ -103,8 +102,11 @@ final class Config
       keyboardHeightPercent = prefs.getInt("keyboard_height", 35);
     }
     layout = layoutId_of_string(prefs.getString("layout", "system"));
-    swipe_dist_dp = Float.valueOf(prefs.getString("swipe_dist", "15"));
-    swipe_dist_px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, swipe_dist_dp, dm);
+    // The swipe distance is defined relatively to the "exact physical pixels
+    // per inch of the screen", which isn't affected by the scaling settings.
+    // Take the mean of both dimensions as an approximation of the diagonal.
+    float physical_scaling = (dm.widthPixels + dm.heightPixels) / (dm.xdpi + dm.ydpi);
+    swipe_dist_px = Float.valueOf(prefs.getString("swipe_dist", "15")) * physical_scaling;;
     vibrateEnabled = prefs.getBoolean("vibrate_enabled", vibrateEnabled);
     vibrateDuration = prefs.getInt("vibrate_duration", (int)vibrateDuration);
     longPressTimeout = prefs.getInt("longpress_timeout", (int)longPressTimeout);