Reimplement "shadow-effect" used by Window- and WorkspaceClone

Based on patch by "Diego Rocha (diego-rocha-comp)"

src/ShadowEffect.vala

@@ -50,13 +50,14 @@ namespace Gala
 		Cogl.Material material;
 		string? current_key = null;
 
-		public ShadowEffect (int actor_width, int actor_height, int shadow_size, int shadow_spread)
+		public ShadowEffect (int shadow_size, int shadow_spread)
 		{
 			Object (shadow_size: shadow_size, shadow_spread: shadow_spread);
+		}
 
+		construct
+		{
 			material = new Cogl.Material ();
-
-			update_size (actor_width, actor_height);
 		}
 
 		~ShadowEffect ()
@@ -65,24 +66,18 @@ namespace Gala
 				decrement_shadow_users (current_key);
 		}
 
-		public void update_size (int actor_width, int actor_height)
+		Cogl.Texture? get_shadow (int width, int height, int shadow_size, int shadow_spread)
 		{
-			var shadow = get_shadow (actor_width, actor_height, shadow_size, shadow_spread);
-			material.set_layer (0, shadow);
-		}
-
-		Cogl.Texture get_shadow (int actor_width, int actor_height, int shadow_size, int shadow_spread)
-		{
-			if (current_key != null) {
-				decrement_shadow_users (current_key);
-			}
-
-			Shadow? shadow = null;
-
-			var width = actor_width + shadow_size * 2;
-			var height = actor_height + shadow_size * 2;
+			var old_key = current_key;
 
 			current_key = "%ix%i:%i:%i".printf (width, height, shadow_size, shadow_spread);
+			if (old_key == current_key)
+				return null;
+
+			if (old_key != null)
+				decrement_shadow_users (old_key);
+
+			Shadow? shadow = null;
 			if ((shadow = shadow_cache.@get (current_key)) != null) {
 				shadow.users++;
 				return shadow.texture;
@@ -91,7 +86,7 @@ namespace Gala
 			// fill a new texture for this size
 			var buffer = new Granite.Drawing.BufferSurface (width, height);
 			buffer.context.rectangle (shadow_size - shadow_spread, shadow_size - shadow_spread,
-				actor_width + shadow_spread * 2, actor_height + shadow_spread * 2);
+				width - shadow_size * 2 + shadow_spread * 2, height - shadow_size * 2 + shadow_spread * 2);
 			buffer.context.set_source_rgba (0, 0, 0, 0.7);
 			buffer.context.fill ();
 
@@ -124,7 +119,12 @@ namespace Gala
 
 		public override void paint (EffectPaintFlags flags)
 		{
-			var size = shadow_size * scale_factor;
+			var bounding_box = get_bounding_box ();
+			var shadow = get_shadow ((int) (bounding_box.x2 - bounding_box.x1), (int) (bounding_box.y2 - bounding_box.y1),
+				shadow_size, shadow_spread);
+
+			if (shadow != null)
+				material.set_layer (0, shadow);
 
 			var opacity = actor.get_paint_opacity () * shadow_opacity / 255;
 			var alpha = Cogl.Color.from_4ub (255, 255, 255, opacity);
@@ -133,10 +133,20 @@ namespace Gala
 			material.set_color (alpha);
 
 			Cogl.set_source (material);
-			Cogl.rectangle (-size, -size, actor.width + size, actor.height + size);
+			Cogl.rectangle (bounding_box.x1, bounding_box.y1, bounding_box.x2, bounding_box.y2);
 
 			actor.continue_paint ();
 		}
+
+		public virtual ActorBox get_bounding_box ()
+		{
+			var size = shadow_size * scale_factor;
+			var bounding_box = ActorBox ();
+
+			bounding_box.set_origin (-size, -size);
+			bounding_box.set_size (actor.width + size * 2, actor.height + size * 2);
+
+			return bounding_box;
+		}
 	}
 }
-

src/Widgets/WindowClone.vala

@@ -20,6 +20,31 @@ using Meta;
 
 namespace Gala
 {
+	class WindowShadowEffect : ShadowEffect
+	{
+		public Meta.Window window { get; construct; }
+
+		public WindowShadowEffect (Meta.Window window, int shadow_size, int shadow_spread)
+		{
+			Object (window: window, shadow_size: shadow_size, shadow_spread: shadow_spread, shadow_opacity: 255);
+		}
+
+		public override ActorBox get_bounding_box ()
+		{
+			var size = shadow_size * scale_factor;
+
+			var input_rect = window.get_buffer_rect ();
+			var outer_rect = window.get_frame_rect ();
+
+			// Occupy only window frame area plus shadow size
+			var bounding_box = ActorBox ();
+			bounding_box.set_origin (-(input_rect.x - outer_rect.x) - size, -(input_rect.y - outer_rect.y) - size);
+			bounding_box.set_size (outer_rect.width + size * 2, outer_rect.height + size * 2);
+
+			return bounding_box;
+		}
+	}
+
 	/**
 	 * A container for a clone of the texture of a MetaWindow, a WindowIcon,
 	 * a close button and a shadow. Used together with the WindowCloneContainer.
@@ -159,8 +184,6 @@ namespace Gala
 
 			if (shadow_update_timeout != 0)
 				Source.remove (shadow_update_timeout);
-
-			window.size_changed.disconnect (update_shadow_size);
 		}
 
 		/**
@@ -198,10 +221,8 @@ namespace Gala
 
 			transition_to_original_state (false);
 
-			var outer_rect = window.get_frame_rect ();
-			shadow_effect = new ShadowEffect (outer_rect.width, outer_rect.height, 40, 5);
-			add_effect_with_name ("shadow", shadow_effect);
-			window.size_changed.connect (update_shadow_size);
+			shadow_effect = new WindowShadowEffect (window, 40, 5);
+			clone.add_effect_with_name ("shadow", shadow_effect);
 
 			if (should_fade ())
 				opacity = 0;
@@ -229,30 +250,6 @@ namespace Gala
 				&& window.get_workspace () != window.get_screen ().get_active_workspace ();
 		}
 
-		/**
-		 * Sets a timeout of 500ms after which, if no new resize action reset it,
-		 * the shadow will be resized and a request_reposition() will be emitted to
-		 * make the WindowCloneContainer calculate a new layout to honor the new size.
-		 */
-		void update_shadow_size ()
-		{
-			if (shadow_update_timeout != 0)
-				Source.remove (shadow_update_timeout);
-
-			shadow_update_timeout = Timeout.add (500, () => {
-				var rect = window.get_frame_rect ();
-				var effect = get_effect ("shadow") as ShadowEffect;
-				effect.update_size (rect.width, rect.height);
-
-				shadow_update_timeout = 0;
-
-				// if there was a size change it makes sense to recalculate the positions
-				request_reposition ();
-
-				return false;
-			});
-		}
-
 		void on_all_workspaces_changed ()
 		{
 			// we don't display windows that are on all workspaces
@@ -344,18 +341,15 @@ namespace Gala
 			};
 			active_shape.allocate (shape_alloc, flags);
 
-			if (clone == null)
+			if (clone == null || dragging)
 				return;
 
-			var actor = window.get_compositor_private () as WindowActor;
+			var actor = (WindowActor) window.get_compositor_private ();
 			var input_rect = window.get_buffer_rect ();
 			var outer_rect = window.get_frame_rect ();
 			var scale_factor = (float)width / outer_rect.width;
 
-			var shadow_effect = get_effect ("shadow") as ShadowEffect;
-			shadow_effect.scale_factor = scale_factor;
-
-			var alloc = ActorBox ();
+			ActorBox alloc = {};
 			alloc.set_origin ((input_rect.x - outer_rect.x) * scale_factor,
 			                  (input_rect.y - outer_rect.y) * scale_factor);
 			alloc.set_size (actor.width * scale_factor, actor.height * scale_factor);
@@ -427,9 +421,9 @@ namespace Gala
 			shadow_transition.progress_mode = MultitaskingView.ANIMATION_MODE;
 
 			if (show)
-				shadow_transition.interval = new Clutter.Interval (typeof (uint8), 0, 255);
+				shadow_transition.interval = new Clutter.Interval (typeof (uint8), shadow_effect.shadow_opacity, 255);
 			else
-				shadow_transition.interval = new Clutter.Interval (typeof (uint8), 255, 0);
+				shadow_transition.interval = new Clutter.Interval (typeof (uint8), shadow_effect.shadow_opacity, 0);
 
 			add_transition ("shadow-opacity", shadow_transition);
 		}
@@ -518,8 +512,6 @@ namespace Gala
 
 			var scale = window_icon.width / clone.width;
 
-			((ShadowEffect) get_effect ("shadow")).shadow_opacity = 0;
-
 			clone.get_transformed_position (out abs_x, out abs_y);
 			clone.save_easing_state ();
 			clone.set_easing_duration (200);
@@ -674,22 +666,13 @@ namespace Gala
 			get_parent ().remove_child (this);
 			prev_parent.insert_child_at_index (this, prev_index);
 
+			clone.set_pivot_point (0, 0);
+
 			clone.save_easing_state ();
 			clone.set_easing_duration (250);
 			clone.set_easing_mode (AnimationMode.EASE_OUT_QUAD);
 			clone.set_scale (1, 1);
 			clone.opacity = 255;
-
-			Clutter.Callback finished = () => {
-				((ShadowEffect) get_effect ("shadow")).shadow_opacity = 255;
-			};
-
-			var transition = clone.get_transition ("scale-x");
-			if (transition != null)
-				transition.completed.connect (() => finished (this));
-			else
-				finished (this);
-
 			clone.restore_easing_state ();
 
 			request_reposition ();

src/Widgets/WorkspaceClone.vala

@@ -35,7 +35,7 @@ namespace Gala
 			var primary = screen.get_primary_monitor ();
 			var monitor_geom = screen.get_monitor_geometry (primary);
 
-			add_effect (new ShadowEffect (monitor_geom.width, monitor_geom.height, 40, 5));
+			add_effect (new ShadowEffect (40, 5));
 		}
 
 		public override void paint ()