modeling masses of books

i’m currently making a library, and books, lots and lots of books,
but really, only the binds of the books show, but to add realism, i need to add variations to the heights of the books, and here comes the problem:
if i was to model a few book, the i can make their height different by hand,but when it comes to thousands with particle systems…



i know that you can make variable sizes in the particle system…
but what if you wanted only the height(z-axis) to vary?
i also tried this (but still failed)


i think i’m close, but i just need to know how can i displace the top as a whole, rather than separate verticies…
if only i can displace bones…

Theres probably some way to use a cuve with a lattice to modify the height of an array of books. I think Andrew Price has a video on a random material assigner.

You might want to try the randomize transform command in object mode, select all your books, click randomize transform and adjust the z x and y heights separately. You will need to use objects align to get them to line up again.anyway you can play with this and it’s a fairly powerful way to work with many objects at a time.
This is a quick ‘proof of’ that shows everything working except for the spacing between the books. So either you go with all the samewidth or adjust it horizontally by hand.