Hi Bo,
I realised myself that drawing directly on the form is unmanageable.
If I understood idea, ImageCanvas is sort of bound to the underlying memory bitmap simillar to ordinary form textbox being bound to a variable or a field and then all refreshing is done automatically.
What is the idea with that ClientWindow ?
By now I found my perfect scenario with ImageCanvas placed within scrollableContainer by CarlosA/MalcolmG.
Don't tell me that I will have to rewrite my stuff again because this one will be like 10 times faster :0)
VFPX rocks :)