BitShares Forum

Other => Graveyard => DAC PLAY => Topic started by: cass on April 17, 2014, 01:54:10 am

Title: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: cass on April 17, 2014, 01:54:10 am
https://www.youtube.com/watch?v=ldJcw7JPHz0&feature=youtu.be

FYI don't know if i post it here correctly, but want to publish this link.
What do you think?
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: bytemaster on April 17, 2014, 02:02:17 am
Funny that HackFisher's name is Denny and he is working on our Lotto...
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: cass on April 17, 2014, 02:06:00 am
Funny that HackFisher's name is Denny and he is working on our Lotto...

^^
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: HackFisher on April 17, 2014, 02:19:25 am
I cannot access youtube temporarily, what's is about, is another "Denny" from Ethereum giving a demo?

I'll watch that later...
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: cass on April 17, 2014, 02:21:08 am
I cannot access youtube temporarily, what's is about, is another "Denny" from Ethereum giving a demo?

I'll watch that later...

yay don't know it it important, but guessing from bytes reply it isn't ^^^just want to let you know about...
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: CLains on April 17, 2014, 01:45:58 pm
Working on the same kind of thing and having the same name is a great point of entry. Destined for collaboration I say. :)
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: HackFisher on April 17, 2014, 03:16:48 pm
interesting... I just watched that, good demo.

similar features, so facing similar problems to resolve, e.g. the part to RNG...

I like this Dennis' humor:)
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: toast on April 17, 2014, 03:18:33 pm
Contact them!

Sent from my SCH-I535 using Tapatalk

Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: HackFisher on April 18, 2014, 02:32:04 am
Contact them!

Sent from my SCH-I535 using Tapatalk

Contacted, it would be great if we can collaborate.
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: bytemaster on April 18, 2014, 05:18:19 am
How did they solve the RNG problem?
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: HackFisher on April 18, 2014, 05:58:20 am
How did they solve the RNG problem?

https://github.com/dennismckinnon/Ethereum-Contracts/blob/master/Dennys%20Lotto/Lottery.lsp (https://github.com/dennismckinnon/Ethereum-Contracts/blob/master/Dennys%20Lotto/Lottery.lsp)

Code: [Select]
[0x20] (prevhash)
[0x40] (coinbase)
[0x60] (SHA3 0x20 0x40) ;Random lottery
[0x80] (MOD @0x3 @@0x2) ;DRAW!

From explanation of the demo and code, it seems being use hash of (block info  and prevhash) to resolve the RNG.

I've enclosed this thread's link to Dennis, he perhaps can give more info on that if he come here.
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: gamey on April 18, 2014, 06:02:27 am
How did they solve the RNG problem?

https://github.com/dennismckinnon/Ethereum-Contracts/blob/master/Dennys%20Lotto/Lottery.lsp (https://github.com/dennismckinnon/Ethereum-Contracts/blob/master/Dennys%20Lotto/Lottery.lsp)

Code: [Select]
[0x20] (prevhash)
[0x40] (coinbase)
[0x60] (SHA3 0x20 0x40) ;Random lottery
[0x80] (MOD @0x3 @@0x2) ;DRAW!

From explanation of the demo and code, it seems being use hash of (block info  and prevhash) to resolve the RNG.

I've enclosed this thread's link to Dennis, he perhaps can give more info on that if he come here.

I listened to his youtube on and off.   What I recall is that the "forum" thought hashing the block timestamp was a good idea, but Denny was against that. (for good reason..  the time stamp can be selected within a certain window.)  So he ended up using previous block + current block hashes.
Title: Re: Found this: Denny's Lotto: Ethereum ÐApp demo & walkthrough
Post by: bytemaster on April 18, 2014, 04:38:33 pm
How did they solve the RNG problem?

https://github.com/dennismckinnon/Ethereum-Contracts/blob/master/Dennys%20Lotto/Lottery.lsp (https://github.com/dennismckinnon/Ethereum-Contracts/blob/master/Dennys%20Lotto/Lottery.lsp)

Code: [Select]
[0x20] (prevhash)
[0x40] (coinbase)
[0x60] (SHA3 0x20 0x40) ;Random lottery
[0x80] (MOD @0x3 @@0x2) ;DRAW!

From explanation of the demo and code, it seems being use hash of (block info  and prevhash) to resolve the RNG.

I've enclosed this thread's link to Dennis, he perhaps can give more info on that if he come here.

I listened to his youtube on and off.   What I recall is that the "forum" thought hashing the block timestamp was a good idea, but Denny was against that. (for good reason..  the time stamp can be selected within a certain window.)  So he ended up using previous block + current block hashes.

This design only works because ethereum is mining based and thus it is difficult to produce a winning block in the first place.