Hi!
A friend has coded electrum compatible public key generation from mpk (master public key) in pure php.
Code:
https://gist.github.com/sembrestels/5948996This allows php sites to work with addresses from an electrum compatible wallet so they can generate any of the receiving addresses without real access to funds.
This is his first bitcoin related code. If this is useful for your project consider making a donation to the following address:
1N67cWXfuAZPJa9rb8fBVfdX2Gb8xb8Yi7
Code based on electrum python code and the following gist:
https://gist.github.com/scintill/3549107, using php ecdsa and big number libraries.
Developed as a first stage for integrating payments into elgg (an open source social networking software).
Cheers!