I've been bashing my head for the past couple of weeks trying to find a way to help me accomplish, on first look very easy task. So, I got this one object currently made out of 5 cuboids (2 sides, 1 top, 1 bottom, 1 back), this is just for an example, later on there will be whole range of different set ups. Now, the thing is when the user chooses to scale the whole object this is what should happen:

X scale: top and bottom cuboids should get scaled by a scale factor, sides should get moved so they are positioned just like they were before(in this case at both ends of top and bottom cuboids), back should get scaled so it fits like before(if I simply scale it by a scale factor it will leave gaps on each side).

Y scale: sides should get scaled by a scale factor, top and bottom cuboid should get moved, and back should also get scaled.

Z scale: sides, top and bottom cuboids should get scaled, back should get moved.

Hope you can help,

EDIT: So, I've decided to explain the situation once more, this time more detailed(hopefully). I've also made some pictures of how the scaling should look like, where is the problem and the wrong way of scaling.

I this example I will be using a thick walled box, with one face missing, where each wall is made by a cuboid(but later on there will be diffrent shapes of objects, where a one of the face might be roundish, or triangle or even under some angle), scaling will be 2x on X axis.

1.This is how the default object without any scaling applied looks like: http://img856.imageshack.us/img856/4293/defaulttz.png

2.If I scale the whole object(all of the meshes) by some scale factor, the problem becomes that the "thickness" of the object walls also change(which I do not want): http://img822.imageshack.us/img822/9073/wrongwaytoscale.png

3.This is how the correct scaling should look like. Appropriate faces gets caled in this case where the scale is on X axis(top, bottom, back): http://imageshack.us/photo/my-images/163/rightwayxscale1.png/

4.But the scale factor might not be the same for all object all of the times. In this case the back has to get scaled a bit more or it leaves gaps: http://imageshack.us/photo/my-images/9/problemwhenscaling.png/

5.If everything goes well this is how the final object should look like: http://imageshack.us/photo/my-images/856/rightwayxscale2.png/

So, as you have might noticed there are quite a bit of things to look out when scaling. I am asking you, if any of you have any idea on how to accomplish this scaling. I have tried whole bunch of things, from scaling all of the object by the same scale factor, to subtracting and adding sizes to get the right size. But nothing I tried worked, if one mesh got scaled correctly then others didnt.

Donwload the example object.

English is not my first language, so I am really sorry if its hard to understand what I am saying.