userLocationMarker: Rotate around center of iconwip/mlundblad/fix-compass-rotation

When there's a location heading (showing the compass location
icon), apply appropriate translation transforms when rotating
to get rotation around the icon's center point.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/userLocationMarker.js b/src/userLocationMarker.js
index 173b296b..26fcc8d4 100644
--- a/src/userLocationMarker.js
+++ b/src/userLocationMarker.js
@@ -130,7 +130,15 @@ export class UserLocationMarker extends MapMarker {
 
     vfunc_snapshot(snapshot) {
         if (this.place.location.heading > -1) {
+            // rotate around the center of the icon
+            let {x, y, width, height} = this.get_allocation();
+            let point = new Graphene.Point();
+
+            point.init(width / 2, height / 2);
+            snapshot.translate(point);
             snapshot.rotate(this.place.location.heading);
+            point.init(-width / 2, -height / 2);
+            snapshot.translate(point);
         }
 
         this.snapshot_child(this._image, snapshot);