spessasynth_lib
Version:
MIDI and SoundFont2/DLS library with no compromises
39 lines (37 loc) • 1.27 kB
JavaScript
import { IndexedByteArray } from "../../../utils/indexed_array.js";
import { writeWord } from "../../../utils/byte_functions/little_endian.js";
import { RiffChunk, writeRIFFChunk } from "../riff_chunk.js";
/**
* @this {BasicSoundBank}
* @returns {IndexedByteArray}
*/
export function getIBAG()
{
// write all ibag with their start indexes as they were changed in getIGEN() and getIMOD()
const ibagsize = this.instruments.reduce((sum, i) => i.instrumentZones.length * 4 + sum, 4);
const ibagdata = new IndexedByteArray(ibagsize);
let zoneID = 0;
let generatorIndex = 0;
let modulatorIndex = 0;
for (const inst of this.instruments)
{
inst.instrumentZoneIndex = zoneID;
for (const ibag of inst.instrumentZones)
{
ibag.zoneID = zoneID;
writeWord(ibagdata, generatorIndex);
writeWord(ibagdata, modulatorIndex);
generatorIndex += ibag.generators.length;
modulatorIndex += ibag.modulators.length;
zoneID++;
}
}
// write the terminal IBAG
writeWord(ibagdata, generatorIndex);
writeWord(ibagdata, modulatorIndex);
return writeRIFFChunk(new RiffChunk(
"ibag",
ibagdata.length,
ibagdata
));
}