iigs-game-engine/tools/png2iigs.js
2021-11-20 11:09:57 -06:00

496 lines
15 KiB
JavaScript

const fs = require('fs').promises;
const PNG = require("pngjs").PNG;
const process = require('process');
const { Buffer } = require('buffer');
const StringBuilder = require('string-builder');
main(process.argv.slice(2)).then(
() => process.exit(0),
(e) => {
console.error(e);
process.exit(1);
}
);
function findColorIndex(options, png, pixel) {
let mask = true;
let index = -1;
for (let i = 0; i < png.palette.length; i += 1) {
const color = png.palette[i].slice(0, pixel.length); // Handle RGB or RGBA
if (color.every((c, idx) => c === pixel[idx])) {
if (i === options.transparentIndex) {
mask = false;
}
index = i + options.startIndex;
}
}
if (index === -1) {
return [null, mask];
}
if (options.paletteMap) {
index = options.paletteMap[index];
}
return [index, mask];
}
function pngToIIgsBuff(options, png) {
let i = 0;
const buff = Buffer.alloc(png.height * (png.width / 2), 0);
const mask = Buffer.alloc(png.height * (png.width / 2), 0);
for (let y = 0; y < png.height; y += 1) {
for (let x = 0; x < png.width; x += 1, i += 4) {
const pixel = png.data.slice(i, i + 4);
const [index, ismask] = findColorIndex(options, png, pixel);
const j = y * (png.width / 2) + Math.floor(x / 2);
if (index > 15) {
console.warn('; Pixel index greater than 15. Skipping...');
continue;
}
if (x % 2 === 0) {
buff[j] = 16 * index;
mask[j] = ismask ? 0 : 240;
}
else {
buff[j] = buff[j] | index;
mask[j] = mask[j] | (ismask ? 0 : 15);
}
}
}
return [buff, mask];
}
function hexStringToPalette(hex) {
return [
parseInt(hex.slice(0,2), 16),
parseInt(hex.slice(2,4), 16),
parseInt(hex.slice(4,6), 16)
];
}
function paletteToHexString(palette) {
const r = Math.round(palette[0]);
const g = Math.round(palette[1]);
const b = Math.round(palette[2]);
return (
r.toString(16).toUpperCase().padStart(2, '0') +
g.toString(16).toUpperCase().padStart(2, '0') +
b.toString(16).toUpperCase().padStart(2, '0')
);
}
function paletteToIIgs(palette) {
const r = Math.round(palette[0] / 17);
const g = Math.round(palette[1] / 17);
const b = Math.round(palette[2] / 17);
return '0' + r.toString(16).toUpperCase() + g.toString(16).toUpperCase() + b.toString(16).toUpperCase();
}
function getArg(argv, arg, fn, defaultValue) {
for (let i = 0; i < argv.length; i += 1) {
if (argv[i] === arg) {
if (fn) {
return fn(argv[i+1]);
}
return true; // Return true if the argument was found
}
}
return defaultValue;
}
async function readPNG(filename) {
const data = await fs.readFile(filename);
const png = PNG.sync.read(data);
if (png.colorType !== 3) {
throw new Error('PNG must be in palette color type');
}
if (png.palette.length > 16) {
throw new Error(`Too many colors. Must be 16 or less. Found ${png.palette.length}`);
}
return png;
}
function getOptions(argv) {
const options = {};
options.startIndex = getArg(argv, '--start-index', x => parseInt(x, 10), 0);
options.asTileData = getArg(argv, '--as-tile-data', x => true, false);
options.maxTiles = getArg(argv, '--max-tiles', x => parseInt(x, 10), 511);
options.transparentIndex = getArg(argv, '--transparent-color-index', x => parseInt(x, 10), -1);
options.transparentColor = getArg(argv, '--transparent-color', x => x, null);
options.backgroundColor = getArg(argv, '--background-color', x => x, null);
options.targetPalette = getArg(argv, '--palette', x => x.split(',').map(c => hexStringToPalette(c)), null)
return options;
}
function getPaletteMap(options, png) {
// Get the RGB triplets from the palette
const sourcePalette = png.palette;
const targetPalette = options.targetPalette || sourcePalette;
const paletteCSSTripplets = sourcePalette.map(c => paletteToHexString(c));
// Start with an identity map
const paletteMap = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15];
// If there is a transparent color / color index, make sure it gets mapped to index 0
if (options.transparentIndex > 0) {
paletteMap[options.transparentIndex] = 0;
}
if (options.transparentColor !== null) {
const index = paletteCSSTripplets.findIndex(p => p === options.transparentColor);
if (index !== -1) {
options.transparentIndex = index;
paletteMap[index] = 0;
} else {
console.warn(`; transparent color defined, ${options.transparentColor}, but not found in image`);
}
}
// Match up the source palette with the target palette
const targetTriplets = targetPalette.map(c => paletteToHexString(c));
paletteCSSTripplets.forEach((color, i) => {
if (i !== options.transparentIndex) {
const j = targetTriplets.findIndex(p => p === color);
if (j !== -1) {
console.warn(`Assigned color index ${i} (${color}) to the target palette index ${j}`);
paletteMap[i] = j;
} else {
console.warn(`Could not map color index ${i} (${color}) to the target palette`);
}
}
});
return {
paletteMap,
sourcePalette,
targetPalette
};
}
async function main(argv) {
// try {
const png = await readPNG(argv[0]);
const options = getOptions(argv);
console.info(`; startIndex = ${options.startIndex}`);
if (png.colorType !== 3) {
console.warn('; PNG must be in palette color type');
return;
}
if (png.palette.length > 16) {
console.warn('; Too many colors. Must be 16 or less');
return;
}
if (options.palette && options.palette.length > 16) {
console.warn('; Too many colors on command line. Must be 16 or less');
return;
}
// Get the RGB triplets from the palette
const { targetPalette, paletteMap } = getPaletteMap(options, png);
options.paletteMap = paletteMap;
// Dump the palette in IIgs hex format
console.log('; Palette:');
const hexCodes = targetPalette.map(c => '$' + paletteToIIgs(c));
// The transparent color is always mapped into color 0, so if a background color is set it goes into index 0
if (options.backgroundColor !== null) {
hexCodes[0] = '$' + paletteToIIgs(hexStringToPalette(options.backgroundColor));
}
console.log(';', hexCodes.join(','));
// Just convert a paletted PNG to IIgs memory format. We make sure that only a few widths
// are supported
let buff = null;
let mask = null;
console.log('; Converting to BG0 format...');
[buff, mask] = pngToIIgsBuff(options, png);
if (buff && argv[1]) {
if (options.asTileData) {
writeToTileDataSource(options, buff, mask, png.width / 2);
}
else {
console.log(`; Writing to output file ${argv[1]}`);
await writeBinayOutput(options, argv[1], buff);
}
}
//}
// catch (e) {
// console.log(`; ${e}`);
// process.exit(1);
//}
}
function reverse(str) {
return [...str].reverse().join(''); // use [...str] instead of split as it is unicode-aware.
}
function toHex(h) {
return h.toString(16).padStart(2, '0');
}
function swap(hex) {
const high = hex & 0xF0;
const low = hex & 0x0F;
return (high >> 4) | (low << 4);
}
function toMask(hex, transparentIndex) {
if (transparentIndex === -1) {
return 0;
}
const indexHigh = (transparentIndex & 0xF) << 4;
const indexLow = (transparentIndex & 0xF);
let mask = 0;
if ((hex & 0xF0) === indexHigh) {
mask = mask | 0xF0;
}
if ((hex & 0x0F) === indexLow) {
mask = mask | 0x0F;
}
return mask;
}
/**
* Return all four 32 byte chunks of data for a single 8x8 tile
*/
function buildTile(options, buff, _mask, width, x, y) {
const tile = {
isSolid: true,
normal: {
data: [],
mask: []
},
flipped: {
data: [],
mask: []
}
};
const offset = y * width + x;
for (dy = 0; dy < 8; dy += 1) {
const hex0 = buff[offset + dy * width + 0];
const hex1 = buff[offset + dy * width + 1];
const hex2 = buff[offset + dy * width + 2];
const hex3 = buff[offset + dy * width + 3];
const mask0 = _mask[offset + dy * width + 0];
const mask1 = _mask[offset + dy * width + 1];
const mask2 = _mask[offset + dy * width + 2];
const mask3 = _mask[offset + dy * width + 3];
const data = [hex0, hex1, hex2, hex3];
const mask = [mask0, mask1, mask2, mask3]; // raw.map(h => toMask(h, options.transparentIndex));
// const data = raw.map((h, i) => h & ~mask[i]);
tile.normal.data.push(data);
tile.normal.mask.push(mask);
// If we run across any non-zero mask value, then the tile is not solid
if (mask.some(h => h != 0)) {
tile.isSolid = false;
}
}
for (dy = 0; dy < 8; dy += 1) {
const hex0 = swap(buff[offset + dy * width + 0]);
const hex1 = swap(buff[offset + dy * width + 1]);
const hex2 = swap(buff[offset + dy * width + 2]);
const hex3 = swap(buff[offset + dy * width + 3]);
const mask0 = swap(_mask[offset + dy * width + 0]);
const mask1 = swap(_mask[offset + dy * width + 1]);
const mask2 = swap(_mask[offset + dy * width + 2]);
const mask3 = swap(_mask[offset + dy * width + 3]);
const data = [hex3, hex2, hex1, hex0];
const mask = [mask3, mask2, mask1, mask0]; // raw.map(h => toMask(h, options.transparentIndex));
// const data = raw.map((h, i) => h & ~mask[i]);
tile.flipped.data.push(data);
tile.flipped.mask.push(mask);
}
return tile;
}
function buildTiles(options, buff, mask, width) {
const tiles = [];
let count = 0;
for (let y = 0; ; y += 8) {
for (let x = 0; x < width; x += 4, count += 1) {
if (count >= options.maxTiles) {
return tiles;
}
const tile = buildTile(options, buff, mask, width, x, y);
// Tiled TileIDs start at 1
tile.tileId = count + 1;
tiles.push(tile);
}
}
}
function writeTileToStream(stream, data) {
// Output the tile data
for (const row of data) {
const hex = row.map(d => toHex(d)).join('');
stream.write(' hex ' + hex + '\n');
}
}
function writeTilesToStream(options, stream, tiles, label='tiledata') {
stream.write(`${label} ENT\n`);
stream.write('');
stream.write('; Reserved space (tile 0 is special...)\n');
stream.write(' ds 128\n');
let count = 0;
for (const tile of tiles.slice(0, options.maxTiles)) {
console.log(`Writing tile ${count + 1}`);
stream.write(`; Tile ID ${count + 1}, isSolid: ${tile.isSolid}\n`);
writeTileToStream(stream, tile.normal.data);
writeTileToStream(stream, tile.normal.mask);
writeTileToStream(stream, tile.flipped.data);
writeTileToStream(stream, tile.flipped.mask);
stream.write('');
count += 1;
}
}
function buildMerlinCodeForTile(data) {
const sb = new StringBuilder();
// Output the tile data
for (const row of data) {
const hex = row.map(d => toHex(d)).join('');
sb.appendLine(' hex ' + hex);
}
return sb.toString();
}
function buildMerlinCodeForTiles(options, tiles, label='tiledata') {
const sb = new StringBuilder();
sb.appendLine(`${label} ENT`);
sb.appendLine();
sb.appendLine('; Reserved space (tile 0 is special...)');
sb.appendLine(' ds 128');
let count = 0;
for (const tile of tiles.slice(0, options.maxTiles)) {
console.log(`Writing tile ${count + 1}`);
sb.appendLine(`; Tile ID ${count + 1}, isSolid: ${tile.isSolid}`);
sb.append(buildMerlinCodeForTile(tile.normal.data));
sb.append(buildMerlinCodeForTile(tile.normal.mask));
sb.append(buildMerlinCodeForTile(tile.flipped.data));
sb.append(buildMerlinCodeForTile(tile.flipped.mask));
sb.appendLine();
count += 1;
}
return sb.toString();
}
function writeToTileDataSource(options, buff, mask, width) {
console.log('tiledata ENT');
console.log();
console.log('; Reserved space (tile 0 is special...');
console.log(' ds 128');
let count = 0;
for (let y = 0; ; y += 8) {
for (let x = 0; x < width; x += 4, count += 1) {
if (count >= options.maxTiles) {
return;
}
console.log('; Tile ID ' + (count + 1));
console.log('; From image coordinates ' + (x * 2) + ', ' + y);
const tile = buildTile(options, buff, mask, width, x, y);
// Output the tile data
for (const row of tile.normal.data) {
const hex = row.map(d => toHex(d)).join('');
console.log(' hex ' + hex);
}
console.log();
// Output the tile mask
for (const row of tile.normal.mask) {
const hex = row.map(d => toHex(d)).join('');
console.log(' hex ' + hex);
}
console.log();
// Output the flipped tile data
for (const row of tile.flipped.data) {
const hex = row.map(d => toHex(d)).join('');
console.log(' hex ' + hex);
}
console.log();
// Output the flipped tile data
for (const row of tile.flipped.mask) {
const hex = row.map(d => toHex(d)).join('');
console.log(' hex ' + hex);
}
console.log();
}
}
}
async function writeBinayOutput(options, filename, buff) {
// Write a small header. This is useful and avoids triggering a sparse file load
// bug when the first block of the file on the GS/OS drive is sparse.
// Put the ASCII text of "GTERAW" in the first 6 bytes
const header = Buffer.alloc(8);
header.write('GTERAW', 'latin1');
// Use the special value $A5A5 to identify no transparency
if (options.transparentIndex < 0) {
header.writeUInt16LE(0xA5A5);
} else {
header.writeUInt16LE(0x1111 * options.transparentIndex, 6);
}
await fs.writeFile(filename, Buffer.concat([header, buff]));
}
module.exports = {
buildTile,
buildTiles,
buildMerlinCodeForTiles,
buildMerlinCodeForTile,
findColorIndex,
getPaletteMap,
paletteToIIgs,
pngToIIgsBuff,
readPNG,
toHex,
writeBinayOutput,
writeToTileDataSource,
writeTilesToStream
}