Draw optimizer

src/Tools/BaseTool.gd

@@ -8,6 +8,9 @@ var cursor_text := ""
 
 var _cursor := Vector2.INF
 
+var _draw_cache: PoolVector2Array = []  # for storing already drawn pixels
+var _for_frame := 0  # cache for which frame?
+
 
 func _ready() -> void:
 	kname = name.replace(" ", "_").to_lower()
@@ -40,6 +43,7 @@ func update_config() -> void:
 
 
 func draw_start(_position: Vector2) -> void:
+	_draw_cache = []
 	is_moving = true
 
 
@@ -52,6 +56,7 @@ func draw_move(position: Vector2) -> void:
 
 func draw_end(_position: Vector2) -> void:
 	is_moving = false
+	_draw_cache = []
 
 
 func cursor_move(position: Vector2) -> void:

src/Tools/Draw.gd

@@ -2,6 +2,7 @@ extends BaseTool
 
 var _brush := Brushes.get_default_brush()
 var _brush_size := 1
+var _cache_limit: int = 3
 var _brush_interpolate := 0
 var _brush_image := Image.new()
 var _brush_texture := ImageTexture.new()
@@ -43,6 +44,7 @@ func _on_Brush_selected(brush: Brushes.Brush) -> void:
 
 func _on_BrushSize_value_changed(value: float) -> void:
 	_brush_size = int(value)
+	_cache_limit = (_brush_size * _brush_size) * 3  # This equation seems the best match
 	update_config()
 	save_config()
 
@@ -345,6 +347,13 @@ func draw_indicator_at(position: Vector2, offset: Vector2, color: Color) -> void
 
 
 func _set_pixel(position: Vector2, ignore_mirroring := false) -> void:
+	if position in _draw_cache and _for_frame == Global.current_project.current_frame:
+		return
+	if _draw_cache.size() > _cache_limit or _for_frame != Global.current_project.current_frame:
+		_draw_cache = []
+		_for_frame = Global.current_project.current_frame
+	_draw_cache.append(position)  # Store the position of pixel
+
 	var project: Project = Global.current_project
 	if project.tile_mode and project.get_tile_mode_rect().has_point(position):
 		position = position.posmodv(project.size)