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fix portamentos, pitch bends

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- period slides were off by a factor of 4
 - we need to reset a note's envelope if it was released, and then
   portamento'd into
 - instruments shouldn't trigger notes in the presence of 3xx/5xx
This commit is contained in:
Andy Sloane 2015-10-25 22:06:50 -07:00
commit 50c5513aeb
1 changed files with 12 additions and 6 deletions
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18
xm.js
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@ -78,13 +78,13 @@ popfilter = FilterCoeffs(200.0 / 44100.0);
popfilter_alpha = 0.9837;
function UpdateChannelPeriod(ch, period, f_smp) {
var freq = 8363 * Math.pow(2, (4608 - period) / 768);
var freq = 8363 * Math.pow(2, (1152.0 - period) / 192.0);
ch.doff = freq / f_smp;
ch.filter = FilterCoeffs(ch.doff / 2);
}
function PeriodForNote(ch, note) {
return 7680 - note*64 - ch.inst.fine*0.5;
return 1920 - note*16 - ch.inst.fine / 8.0;
}
function UpdateChannelNote(ch, note, f_smp) {
@ -116,10 +116,8 @@ function next_row(f_smp) {
var inst = instruments[r[i][1] - 1];
if (inst !== undefined) {
ch.inst = inst;
// retrigger?
ch.off = 0;
ch.release = 0;
ch.envtick = 0;
// retrigger unless overridden below
triggernote = true;
// new instrument doesn ot reset volume!
} else {
// console.log("invalid inst", r[i][1], instruments.length);
@ -172,6 +170,12 @@ function next_row(f_smp) {
ch.portaspeed = ch.effectdata;
}
triggernote = false;
if (ch.release) {
// reset envelopes if note was released but leave offset/pitch/etc
// alone
ch.envtick = 0;
ch.release = 0;
}
}
if (triggernote) {
ch.off = 0;
@ -285,6 +289,7 @@ function audio_cb(e) {
var dk = ch.doff;
// console.log(j, offset, ch);
for (var i = offset; i < offset+tickduration; i++) {
if (ch.mute) break;
var s = samp[k|0];
var si = ch.filter[0] * (s + ch.filterstate[0]) + ch.filter[1]*ch.filterstate[1] + ch.filter[2]*ch.filterstate[2];
ch.filterstate[2] = ch.filterstate[1]; ch.filterstate[1] = si; ch.filterstate[0] = s;
@ -371,6 +376,7 @@ function playXM(arrayBuf) {
pan: 128,
vL: 0, vR: 0, // left right volume envelope followers (changes per sample)
vLprev: 0, vRprev: 0,
mute: 0,
})
}
console.log("header len " + hlen);