Darken blocks out of dragged scope

Darken the block trees that cannot be snapped to by the currently dragged block.

addons/block_code/drag_manager/drag_manager.gd

@@ -122,6 +122,9 @@ func drag_block(block: Block, copied_from: Block = null):
 	drag_offset = get_local_mouse_position() - block.position
 	dragging = block
 
+	if block.scope != "":
+		_block_canvas.set_scope(block.scope)
+
 
 func copy_block(block: Block) -> Block:
 	return block.duplicate(DUPLICATE_USE_INSTANTIATION)  # use instantiation
@@ -163,6 +166,8 @@ func drag_ended():
 		else:
 			dragging.queue_free()
 
+		_block_canvas.release_scope()
+
 		dragging = null
 		block_dropped.emit()
 

addons/block_code/ui/block_canvas/block_canvas.gd

@@ -115,3 +115,20 @@ func find_snaps(node: Node) -> Array:
 			snaps.append_array(find_snaps(c))
 
 	return snaps
+
+
+func set_scope(scope: String):
+	for block in _window.get_children():
+		if block is EntryBlock:
+			var entry_block = block as EntryBlock
+
+			if scope != entry_block.get_entry_statement():
+				entry_block.modulate = Color(0.5, 0.5, 0.5, 1)
+
+
+func release_scope():
+	for block in _window.get_children():
+		if block is EntryBlock:
+			var entry_block = block as EntryBlock
+
+			entry_block.modulate = Color.WHITE