fix: reset Coordinate Transformation Matrix to identity in start.sh

The Wacom driver can initialise the CTM to all-zeros, which maps every touch event to screen coordinate (0,0). The touchscreen appears completely dead even though the hardware and kernel are working correctly. Reset the CTM to the identity matrix for every touch/finger device at startup, before launching Electron, so coordinates are always correct. https://claude.ai/code/session_01EyjEQLWbTXcZgbMDarf7NU
2026-06-16 13:44:50 +00:00
parent 14172782c9
commit 3315ccc44a
1 changed files with 7 additions and 4 deletions
@@ -7346,11 +7346,14 @@ for i in {1..10}; do
    sleep 1
 done

-# Enable multi-touch gesture support for any detected touch screen
-# Wacom devices require "Wacom Enable Touch Gesture" to be set (defaults to 0).
-# The set-prop call is silently ignored for non-Wacom devices that don't have this property.
-# Excludes touchpads — only targets touch screens and finger-touch digitizers.
+# Fix touch device coordinate mapping and enable multi-touch gestures.
+# Loop over all touch/finger input devices (excludes touchpads).
 while IFS= read -r dev; do
+  # Reset Coordinate Transformation Matrix to identity — without this,
+  # the Wacom driver can initialise the CTM to all-zeros, which maps
+  # every touch to (0,0) on screen and makes the touchscreen appear dead.
+  xinput set-prop "$dev" "Coordinate Transformation Matrix" 1 0 0 0 1 0 0 0 1 2>/dev/null || true
+  # Enable multi-touch gesture mode (Wacom-specific; ignored by other drivers).
  xinput set-prop "$dev" "Wacom Enable Touch Gesture" 1 2>/dev/null || true
 done < <(xinput list --name-only 2>/dev/null | grep -i "touch\|finger" | grep -iv "touchpad\|trackpad")