Interactive Graphic Coding for Wordpress site - colour changing umbrella

Hello - www.squidlondon.com 's umbrellas change colour in the rain.
And here is the problem - how could you show this in an interactive way on SquidLondon's wordpress site?

See images attached - ideally the mouse changes into a raindrop or paint brush. For our homepage - we would like to have our designs change when moving with the mouse over it.

Example:
When moving with the mouse over certain parts of the white design on the dry umbrella, the white design changes to the wet pattern underneath.
See similar coding:http://aquadoodle.com/

For more inspiration see:
http://jacksonpollock.org/

If you are that genius who has an idea how to implement this on our wordpress site - please say hello. Our Head office is based in London but you could be based anywhere in the world thanks to Skype and email. After agreeing on price and time, we would put you in touch with SquidLondon's wordpress webdeveloper.


Happy rainy days and looking forward to your application!