function update_brush_for_drawing_lines(stroke_size) {
	if (aliasing && stroke_size > 1) {
		line_brush_canvas = get_brush_canvas("circle", stroke_size);
	}
}
Updates the brush canvas used for line drawing.

USAGE NOTE: must be called outside of any other usage of op_canvas (because of render_brush)

@param {number} stroke_size - The line width of the stroke.