Merge pull request #121 from asaaki/fix/minimize-crash

Allow minimising

bevy_kayak_renderer/src/render/ui_pass.rs

@@ -62,10 +62,12 @@ impl Node for MainPassUINode {
         world: &World,
     ) -> Result<(), NodeRunError> {
         let view_entity = graph.get_input_entity(Self::IN_VIEW)?;
-        let (transparent_phase, target) = self
-            .query
-            .get_manual(world, view_entity)
-            .expect("view entity should exist");
+        // adapted from bevy itself;
+        // see: <https://github.com/bevyengine/bevy/commit/09a3d8abe062984479bf0e99fcc1508bb722baf6>
+        let (transparent_phase, target) = match self.query.get_manual(world, view_entity) {
+            Ok(it) => it,
+            _ => return Ok(()),
+        };
         // let clear_color = world.get_resource::<ClearColor>().unwrap();
         {
             let pass_descriptor = RenderPassDescriptor {