Always scroll block canvas to the top-left block on open

Author: dylanmccall

addons/block_code/ui/block_canvas/block_canvas.gd

@@ -4,6 +4,7 @@ extends MarginContainer
 
 const EXTEND_MARGIN: float = 800
 const BLOCK_AUTO_PLACE_MARGIN: Vector2 = Vector2(16, 8)
+const DEFAULT_WINDOW_MARGIN: Vector2 = Vector2(24, 24)
 const ZOOM_FACTOR: float = 1.1
 
 @onready var _window: Control = %Window
@@ -31,6 +32,7 @@ var _panning := false
 var zoom: float:
 	set(value):
 		_window.scale = Vector2(value, value)
+		_zoom_label.text = "%.1fx" % value
 	get:
 		return _window.scale.x
 
@@ -117,6 +119,8 @@ func bsd_selected(bsd: BlockScriptData):
 		_selected_node_label.text = _selected_node_label_format.format({"node": edited_node.name})
 		_add_block_code_button.disabled = false
 
+	reset_window_position()
+
 
 func _load_bsd(bsd: BlockScriptData):
 	for tree in bsd.block_trees.array:
@@ -227,6 +231,10 @@ func _input(event):
 			set_mouse_override(event.pressed)
 
 	if event is InputEventMouseButton:
+		if event.button_index == MOUSE_BUTTON_RIGHT and event.is_pressed():
+			reset_window_position()
+			return
+			
 		if event.button_index == MOUSE_BUTTON_LEFT or event.button_index == MOUSE_BUTTON_MIDDLE:
 			if event.pressed and is_mouse_over():
 				_panning = true
@@ -246,15 +254,28 @@ func _input(event):
 			if event.button_index == MOUSE_BUTTON_WHEEL_DOWN and zoom > 0.2:
 				zoom /= ZOOM_FACTOR
 
-			_zoom_label.text = "%.1fx" % zoom
-
 			_window.position -= (old_mouse_window_pos - canvas_to_window(relative_mouse_pos)) * zoom
 
 	if event is InputEventMouseMotion:
 		if (Input.is_key_pressed(KEY_SHIFT) and _panning) or (Input.is_mouse_button_pressed(MOUSE_BUTTON_MIDDLE) and _panning):
 			_window.position += event.relative
 
 
+func reset_window_position():
+	# Generate a bounding box from all of the blocks in the canvas
+
+	var blocks = get_blocks()
+	var top_left: Vector2 = blocks.pop_front().position if blocks.size() > 0 else Vector2(0, 0)
+
+	for block in blocks:
+		if block.position.x < top_left.x:
+			top_left.x = block.position.x
+		if block.position.y < top_left.y:
+			top_left.y = block.position.y
+
+	_window.position = -top_left + DEFAULT_WINDOW_MARGIN
+
+
 func canvas_to_window(v: Vector2) -> Vector2:
 	return _window.get_transform().affine_inverse() * v
 
@@ -274,3 +295,7 @@ func set_mouse_override(override: bool):
 	else:
 		_mouse_override.mouse_filter = Control.MOUSE_FILTER_IGNORE
 		_mouse_override.mouse_default_cursor_shape = Control.CURSOR_ARROW
+
+
+func _on_window_resized():
+	pass