This is giving back the measurement of the perimeter lines of the polygon, not the SQ Volumetric Data. If i draw a polygon i want to know how many square meters that is… not the measurement of the polygon. The polygon is generally ideal for the SQ volume (sq meters / sq miles) which is why MapBox has a triangulation API. The polygon should be hooked up to the MapBox triangulation API and not the measurement alone. The line draw mode is used for measuring and the poly mode should be used for volumetric data, imo. Can this be added to it?
If the expected outcome is that it currently should do what i just described, then it is not giving the correct data. I saw the polygon area call, and assumed it was volumetric since AREA is a volumetric word. If it is just the outside lines, then it should be polygon perimeter NOT area.