y-axis coordinate of the element which has the smaller y-axis coordinate value in the current user coordinate system.
The property is a length with raw measurement value and its units (e.g., 1 inch, 2.5 centimeters, etc). When the element needs to get the x-axis coordinate in pixels, this property converts the raw measurement value using the RSSVG.TSVGGraphicElement.GetUnitFactors (e.g., 1 inch = 96 pixels) .
The Xu, Yu, WidthU, and HeightU properties specify coordinates in virtual pixels of the nearest viewbox, or coordinate system. For example, a TSVGDocument may specify a ViewBox of 0, 0, 100, 100. Specifying an element's X and Y as 50, 50 will always position the element to start in the exact center of the view box. If the TSVGDocument is then drawn to a true pixel rectangle of 1000 pixel width and 500 pixel height, the element would draw at 500, 250 pixels.
Note that this property is before any transformation (i.e., RSSVG.TSVGGraphicElement.Matrix property) is applied