As described in the white paper, the cross-chain function in Vite will support asset transfer through cross-chain gateway. For every target chain, there is a gateway for this purpose. The gateway will listen to the transactions on both chains. If this is a Bitcoin gateway and someone wants to transfer 1 BTC to Vite, he should send the BTC to Bitcoin gateway first, once the gateway discovers the transaction it would wait a certain time for confirmation and then send 1 BTC to the person's Vite address, and vice versa.
Cross-chain smart contract call is not supported at this time.
We appreciate your concerns about our DEX implementation. Vite DEX adopts maker-taker model for order matching. Loopring is not implemented at this time cause considering at the beginning phrase of DEX there won’t be a large number of orders and pairs. And Loopring only shows its advantages when many orders are waiting to be matched in different pairs. When Vite MainNet launches, we still may consider to bring Loopring on-board once situation fits.