New overlay system that reimplements how overlays are drawn (#418)

* New overlay system that reimplements how overlays are drawn

* Fix overlay message declaration

* Fix small mistake

* WIP (broken) changes to plumb the overlay document

* Fix confusion over messaging system architecture

* Removed log

* Overlay system working

* (broken) WIP overlay association

* Finish the overlay system (except test failure)

* Change back IDs in test

* Fixed test, but stilled fails due to revealed real problem with layer reordering selection

* Disable broken test that has a bug in issue #444

Co-authored-by: Dennis <dennis@kobert.dev>
Co-authored-by: otdavies <oliver@psyfer.io>

graphene/src/layers/mod.rs

@@ -86,7 +86,6 @@ pub struct Layer {
 	pub cache_dirty: bool,
 	pub blend_mode: BlendMode,
 	pub opacity: f64,
-	pub overlay: bool,
 }
 
 impl Layer {
@@ -101,7 +100,6 @@ impl Layer {
 			cache_dirty: true,
 			blend_mode: BlendMode::Normal,
 			opacity: 1.,
-			overlay: false,
 		}
 	}
 
@@ -116,7 +114,7 @@ impl Layer {
 		if self.cache_dirty {
 			transforms.push(self.transform);
 			self.thumbnail_cache.clear();
-			self.data.render(&mut self.thumbnail_cache, transforms, if self.overlay { ViewMode::Normal } else { view_mode });
+			self.data.render(&mut self.thumbnail_cache, transforms, view_mode);
 
 			self.cache.clear();
 			let _ = writeln!(self.cache, r#"<g transform="matrix("#);
@@ -137,7 +135,7 @@ impl Layer {
 	}
 
 	pub fn intersects_quad(&self, quad: Quad, path: &mut Vec<LayerId>, intersections: &mut Vec<Vec<LayerId>>) {
-		if !self.visible || self.overlay {
+		if !self.visible {
 			return;
 		}
 		let transformed_quad = self.transform.inverse() * quad;
@@ -179,7 +177,6 @@ impl Clone for Layer {
 			cache_dirty: true,
 			blend_mode: self.blend_mode,
 			opacity: self.opacity,
-			overlay: self.overlay,
 		}
 	}
 }