Transform LIGHT_VEC for rotated and/or flipped Polygon2D - CanvasShader

[system]

	Attention	Topic was automatically imported from the old Question2Answer platform.
	Asked By	vtepe

Is there any way to get a polygon transform inside the shader using built-ins and then flip/rotate LIGHT_VEC to match the actual position? Or is there a proper way to pass it into the shader before every frame?