From: Yariv Barkan <nushoin@users.noreply.github.com>
Date: Sat, 14 Dec 2019 09:27:44 +0000 (+0200)
Subject: demo: Use pinch translation in the gestures demo
X-Git-Tag: archive/raspbian/4.4.1+ds1-2+rpi1^2~18^2~20^2~309^2
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=1a9b1f38a4c8ebcc025bb4cc2583aecbf62b67fc;p=gtk4.git

demo: Use pinch translation in the gestures demo

Add the pinch translation offset to the pinch gesture demo. That allows
moving the square around in addition to the already-supported rotate and
zoom.
---

diff --git a/demos/gtk-demo/gestures.c b/demos/gtk-demo/gestures.c
index 8d53ae3434..4079ed950f 100644
--- a/demos/gtk-demo/gestures.c
+++ b/demos/gtk-demo/gestures.c
@@ -94,9 +94,12 @@ drawing_area_draw (GtkDrawingArea *area,
       cairo_pattern_t *pat;
       cairo_matrix_t matrix;
       gdouble angle, scale;
+      gdouble x_center, y_center;
+
+      gtk_gesture_get_bounding_box_center (GTK_GESTURE (zoom), &x_center, &y_center);
 
       cairo_get_matrix (cr, &matrix);
-      cairo_matrix_translate (&matrix, width / 2, height / 2);
+      cairo_matrix_translate (&matrix, x_center, y_center);
 
       cairo_save (cr);