Viewport out of control (most probably a layout question)

[Thorsten Karrer <thorsten karrer rwth-aachen de>]

Hello everybody,

I must admit that I'm a gtk noob (just started to use it yesterday)  
but I couldn't figure it out by myself...

I try to achieve the following:
I want to display a smaller part of a bigger image in a window  
alongside with some buttons. The image part should NOT have  
scrollbars but be scrollable in a grab-n-drag like fashion (like with  
the grab cursor in photoshop).
My initial solution was to load the image as a gtk_image and put it  
into a gtk_viewport then catch any clicks on the viewport and adjust  
its gtk_adjustments accordingly. That scrolling kind of worked BUT...  
the viewport always resizes itself initially to be as big as the  
whole image - blowing my app's layout and extending well beyond my  
app's window.
It works as expected with a gtk_scrolled_window but that shows the  
scrollbars I try to avoid. If I set the policy to show no scrollbars  
the problem returns - a huuuge viewport out of control.

I tried to pack the viewport/scrolled_window together with the  
buttons into hboxes or vboxes or tables... same result.
I am afraid I may not have understood the gtk layout system, yet... :-?

Thanks for your help!

        Thorsten