Drag-scrolling a group

[Devin Asay]

Hi all,

Has anyone worked out  a method for drag-scrolling a group? I have a simple game in which play area may be smaller than the working screenrect on some screens. I lock the group so that it's always the same size as the stack window, then I just set the scroll of the group to show part of the play area that is in view. I've worked out how to do it using the scroll wheel on the mouse, but I also want to be able to drag the play area around with the mouse. It's "sort of" working, but is moving very jerkily.

I'm doing this:

local sDragging, sMouseV, sMouseH

on mouseUp
    put false into sDragging
end mouseUp

on mouseRelease
    put false into sDragging
end mouseRelease

on mouseDown
    if the height of this stack < the maxHeight of this stack OR  \
          the height of this stack < the maxHeight of this stack then
        put true into sDragging
    else
        put false into sDragging
    end if
    put the mouseV into sMouseV
    put the mouseH into sMouseH
end mouseDown

on mouseMove pNewMouseH, pNewMouseV
    if sDragging then
        set the hScroll of me to the hScroll of me - (pNewMouseH -sMouseH)
        set the vScroll of me to the vScroll of me - (pNewMouseV - sMouseV)
    end if
end mouseMove

My math brain is not very sharp today. Ideas?

Thanks,

Devin


Devin Asay
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