Thanks for the answer.
I will look at ScaleTransform.

About version 1.3, any idea when it will be released ?

So at this time I simply call "SetOffscreenSize" with a value greater the default size.

Hello, I want to be able to resize a FrameworkElement at runtime. So I use SizeWidth/SizeHeight. When I scale up I finish by raising a error "Offscreen atlas texture is full. Can't find space for 447x447 rectangle. Please increase Offscreen size in renderer". How can I prevent it ? Looking...