do not change every window every frame in scene viewer

Author: mockersf

examples/tools/scene_viewer/camera_controller_plugin.rs

@@ -177,7 +177,8 @@ fn camera_controller(
             for mouse_event in mouse_events.iter() {
                 mouse_delta += mouse_event.delta;
             }
-        } else {
+        }
+        if mouse_button_input.just_released(options.mouse_key_enable_mouse) {
             for mut window in &mut windows {
                 window.cursor.grab_mode = CursorGrabMode::None;
                 window.cursor.visible = true;