PeachDrawing.Core
PeachDrawing.Core.Canvas
Canvas.TransformScale Property
How much the transforms pushed so far magnify a unit along each axis: the lengths of the images of the unit x and y vectors under the accumulated linear part. A raster region renders at the physical resolution the document asked for <em>after</em> those transforms are applied, so it needs this to pick its pixel pitch; a graphics that does not track transforms reports no magnification.
public virtual (double X,double Y) TransformScale { get; }