Replacing ZoomFactor will be a very breaking change for many customers which we don't intend to do any time soon, so please stop requesting and try to adapt to the ScaleTransform method. One way we can see to make that Xaml layout to work the same as with ZoomFactor is to set fixed size for the ScrollViewer:

scroller.Width = SystemInformation.PrimaryMonitorSize.Width;
scroller.Height = SystemInformation.PrimaryMonitorSize.Height;
 

Another possible way should be to override the MeasureOverride method (e.g. in MyDiagram class above) and divide the base size by current x/y scales.

I hope that helps,
Stoyan

Your solution work in the example i sent, but not in my software.

The example I sent no idea if is related to exact trouble i have, i think yes but now see no.


Nothing I test fix thiis yet.

Instead modify zoomfactor what i suggest is craate new one
ZoomAspectRatio

In that way not broke compatibility, is the same just add
ZoomAspectRatio.FactorX
ZoomAspectRatio.FactorY


About scroll after zoom, that is already solved and working with zoom, is very easy.
The page solution on versión 3.0 is good but broken compatibility with my prevous diagram and features in the software.

I continue researching, thanks for your time, but please try add that feature.

Thanks for your help! I check this soon.

Sorry for my ignorance but how apply/use this class?

public class MyDiagram : Diagram
{
protected override Matrix DocumentToDiagramMatrix
{
get
{
var m = base.DocumentToDiagramMatrix;
m.Scale(0.8, 0.8);
return m;
}
}
}

Faster test and work perfect like i need doing any aspect ratio.!
Sorry again, but how call the class now from C# code


MyDiagram myzoom = new MyDiagram();
myzoom ?

Thanks for your help, sorry for my ignorance.
When the beta text can be removed?

I only have a mínimum trouble with scroll.
Checking what  happen.