cryptoghost.art
Cryptoghost is a NFT that doesn't rely on external hosting for pictures assets. Everything is on the Ethereum blockchain. As long as Ethereum exists, pictures exist.
Non Fungible Token is a growing phenomenon appeared in 2017, It allows people to "own" some image by writing an entry in a Ethereum smart contract. Once your personal ethereum address written in the registry, it is the proof that some token ID is affected to your adress, then by calling some methods in the smart contract, you can trade and transfer your NFT to other ethereum addresses.
Owning a token ID and what else ?
NFTs are often criticized because image sources aren't stored on the blockchain. This is simply because writing data in a smart contract is so expensive that storing an image would cost thousands of dollars of gas fees per image.
Pictures assets must be hosted elsewhere, generally on IPFS or private networks. The art lifespan depends on the lifespan of the ethereum blockchain and the external hosting, if one may disappear, the art disappears.
The particular case of on-chain generated NFTs
Storing pictures on blockchain is not possible, but what about generating files on-demand ?
Cryptoghost represent cryptographics fractals generated from a chosen string
In this case, no need to store the picture somewhere but just the input string in the contract.
Then with solidity the image file can be generated on the fly.
Quickly test it without coding
Go the the Etherscan page of the contract then call the getBitmapFromghostKey function with some string input
The result is some hex-encoded result of a .bmp file, you can quickly generate the file with this website
This is the output bitmap file generated from a smart contract
The solidity source code of the bitmap generator
function getBitmapFromGhostKey(string memory value)
public
view
returns (bytes memory)
{
// The header of the bitmap file, with color palette
bytes memory headers =
hex"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";
bytes memory pixels = new bytes(16384);
// Start position of the next pixel to be colored
int256 x = 64;
int256 y = 64;
// Amount of points already painted, is reset to 0 if next pixel get out of canvas
int256 totalIndex = 0;
string memory directions = value;
bytes memory directionsBytes;
// Fill the bitmap with blank
for (uint256 iFill = 0; iFill < 16384; iFill++) {
pixels[iFill] = bytes1(uint8(255));
}
// We will paint 151 x 64 pixels
for (uint256 i = 0; i < 151; i++) {
// Array of characters, each characters are one direction : up, down, left, upper left etc...
directions = BytesUtils.sha256HexString(directions);
directionsBytes = bytes(directions);
// Calculate position for the next pixel
for (uint256 iChar = 0; iChar < 64; iChar++) {
if (uint8(directionsBytes[iChar]) == 48 || uint8(directionsBytes[iChar]) == 49) {
x += 1;
} else if (uint8(directionsBytes[iChar]) == 50 || uint8(directionsBytes[iChar]) == 51) {
x += -1;
} else if (uint8(directionsBytes[iChar]) == 52 || uint8(directionsBytes[iChar]) == 53) {
y += 1;
} else if (uint8(directionsBytes[iChar]) == 54 || uint8(directionsBytes[iChar]) == 55) {
y += -1;
} else if (uint8(directionsBytes[iChar]) == 56 || uint8(directionsBytes[iChar]) == 57) {
x += 1;
y += 1;
} else if (uint8(directionsBytes[iChar]) == 97 || uint8(directionsBytes[iChar]) == 98) {
x += -1;
y += 1;
} else if (
uint8(directionsBytes[iChar]) == 99 || uint8(directionsBytes[iChar]) == 100
) {
x += 1;
y += -1;
} else if (
uint8(directionsBytes[iChar]) == 101 || uint8(directionsBytes[iChar]) == 102
) {
x += -1;
y += -1;
}
// If next pixel is out of canvas, reset it to center of canvas
if (y >= 128 || y < 0 || x >= 128 || x < 0) {
y = 64;
x = 64;
totalIndex = 0;
}
// Set the pixel color palette index
pixels[uint256(x) + (128 * uint256(127 - y))] = bytes1(
uint8(totalIndex / 38)
);
totalIndex += 1;
}
}
// concatenate headers and pixel values
return BytesUtils.MergeBytes(headers, pixels);
}