Array representing the line dash as the lengths (in pixels) of the painted and unpainted segments, respectively. If the values is nil or an array has no elements, dash is not applied and the line is drawn continuous. The default values is nil. For example, if the array is set, the line will alternate between 10 pixels drawn segment and 15 pixels gap. If is set, the line will be a looped pattern of 10 pixels drawn segment, followed by 5 pixels gap, followed by 15 pixels drawn segment, followed by 8 pixels gap.

Value specifying how far (in pixels) into the dash pattern the line starts. The default value is 0 which means to start interpreting the pattern from the beginning. For example, if 10 is set, the line is drawn with the dash pattern starting at 10 pixels from its beginning.