mkjs/code/audio/nitroAudio.js

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2017-09-08 09:24:16 -07:00
//
// nitroAudio.js
//--------------------
// Provides an interface for playing nds music and sound effects.
// by RHY3756547
//
window.AudioContext = window.AudioContext || window.webkitAudioContext;
window.nitroAudio = new (function() {
var t = this;
var ctx;
t.sounds = [];
t.tick = tick;
t.playSound = playSound;
t.kill = kill;
t.init = init;
t.instaKill = instaKill;
t.sdat = null;
function init(sdat) {
ctx = new AudioContext();
t.ctx = ctx;
var listener = ctx.listener;
listener.dopplerFactor = 1;
listener.speedOfSound = 100/1024; //343.3
SSEQWaveCache.init(sdat, ctx);
t.sdat = sdat;
}
function tick() {
for (var i=0; i<t.sounds.length; i++) {
var snd = t.sounds[i];
snd.seq.tick();
if (snd.obj != null && snd.obj.soundProps != null && snd.panner != null) updatePanner(snd.panner, snd.obj.soundProps);
}
for (var i=0; i<t.sounds.length; i++) {
var snd = t.sounds[i];
snd.dead = snd.seq.dead;
if (snd.dead) {
snd.gainN.disconnect();
t.sounds.splice(i--, 1);
}
}
}
function kill(sound) {
if (!sound.killing) {
sound.killing = true;
sound.seq.kill();
}
}
function instaKill(sound) { //instantly kills a sound
if (sound == null) return;
var ind = t.sounds.indexOf(sound)
sound.gainN.disconnect();
if (ind == -1) return;
t.sounds.splice(ind, 1);
}
function playSound(seqN, params, arcN, obj) { //if arc is not specified, we just play a normal sequence. this allows 3 overloads.
//obj should have a property "soundProps" where it sets its falloff, position and velocity relative to the oberver occasionally
var sound = { dead: false, killing: false, obj: obj };
var output;
if (obj != null) { //if obj is not null then we have a 3d target to assign this sound to.
output = ctx.createPanner();
sound.gainN = ctx.createGain();
sound.gainN.connect(ctx.destination);
output.connect(sound.gainN);
sound.panner = output;
updatePanner(sound.panner, sound.obj.soundProps);
} else {
output = ctx.createGain();
sound.gainN = output;
output.connect(ctx.destination);
}
var player;
if (arcN == null) {
var seq = t.sdat.sections["$INFO"][0][seqN];
if (seq == null) return;
sound.seq = new SSEQPlayer(seq, t.sdat, ctx, output, params);
} else {
var arc = t.sdat.sections["$INFO"][1][arcN];
if (arc == null) return;
var seq = arc.arc.entries[seqN];
if (seq == null) return;
sound.seq = new SSEQPlayer(seq, t.sdat, ctx, output, params);
}
//now that we have the player, package it in an object
t.sounds.push(sound);
return sound;
}
function updatePanner(panner, soundProps) {
if (panner == null || soundProps == null) return;
if (soundProps.pos != null) panner.setPosition(soundProps.pos[0], soundProps.pos[1], soundProps.pos[2]);
//if (soundProps.vel != null) panner.setVelocity(soundProps.vel[0], soundProps.vel[1], soundProps.vel[2]);
if (soundProps.refDistance != null) panner.refDistance = soundProps.refDistance;
if (soundProps.panningModel != null) panner.panningModel = soundProps.panningModel;
if (soundProps.rolloffFactor != null) panner.rolloffFactor = soundProps.rolloffFactor;
}
})();