ScaleBGPic(id, width, height[, smooth])
id to
the specified width and height. You cannot use this function with
the background picture that is currently displayed. If you want
to change the size of this picture, you will have to change the
display size using ChangeDisplaySize().
Hollywood keeps the original picture of every background picture
so that you do not have to do that. Every scaling done with
ScaleBGPic() is made with the original picture and not with a
scaled versions (in contrast to ScaleBrush()).
The original picture will only be deleted if you modify the
background picture's contents using SelectBGPic().
New in V2.0: You can pass #KEEPASPRAT as either width or height.
Hollywood will calculate the size then automatically by taking the
aspect-ratio of the background picture into account.
Starting with Hollywood 2.0, width and height can also be a string
containing a percent specification, e.g. "50%".
Starting with Hollywood 2.5 you can choose to have the scaled graphics
interpolated by passing True in the smooth argument. The graphics will
then be scaled using anti-alias.