Containing area [width, height]
The image that the user is meant to measure
The unit to show on the ruler. e.g. "mm", "cm", "m", "km", "in", "ft", "yd", "mi"
The number of units to display on the ruler
The number of image pixels per unit (label)
How many ticks to show on the ruler. e.g. 1, 2, 4, 8, 10, 16
Whether to show the Protractor tool overlayed on top of the image
Whether to show the Ruler tool overlayed on top of the image
Options for the measurer widget. A virtual ruler and/or protractor.