From 1069cc8a3fd2dc2b3779a66a36979d1dad355256 Mon Sep 17 00:00:00 2001
From: SAKryukov <github@sakryukov.org>
Date: Sun, 20 Aug 2017 19:47:44 -0400
Subject: [PATCH] Fixed adjustPreset in player, to work around two pathological
 cases in instrument .js files (presets): 1) some files have zones with
 zone.keyRangeLow > zone.keyRangeHigh; they are not used anyway and can be
 removed; this is a big performance improved, as, in some files, they reduce
 number of zones by order of magnitude 2) ALL files have zones with 1-semiton
 gaps, such as 0..29, 29..36, and so on. This is methodically totally wrong,
 but works with integer number of semitones. Microtones can be fractional; if,
 for example, the pitch values is 29.1, the zone will never be found, and its
 fallback is a zone at index 0. It produces intolerably bad quality of sound.

The fix is in just one function, just few line; it does not change sounds with integer number of semitones:

this.adjustPreset = function (audioContext, preset) {
    const fixedZones = [];
    for (let zone of preset.zones) {
        if (zone.keyRangeLow > zone.keyRangeHigh) continue; // pathological case, not used anyway
        fixedZones.push(zone);
        this.adjustZone(audioContext, zone);
    } //loop preset.zones
    preset.zones = fixedZones;
    // removing 1-semitone gaps between zones; important for microtones:
    for (let index = 1; index < preset.zones.length; ++index)
        preset.zones[index].keyRangeLow = preset.zones[index - 1].keyRangeHigh;
};
---
 npm/dist/WebAudioFontPlayer.js | 15 +++++++++++----
 npm/src/player.js              | 13 ++++++++++---
 2 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/npm/dist/WebAudioFontPlayer.js b/npm/dist/WebAudioFontPlayer.js
index 5e71ffc..4bfac97 100644
--- a/npm/dist/WebAudioFontPlayer.js
+++ b/npm/dist/WebAudioFontPlayer.js
@@ -296,10 +296,17 @@ function WebAudioFontPlayer() {
 		return envelope;
 	};
 	this.adjustPreset = function (audioContext, preset) {
-		for (var i = 0; i < preset.zones.length; i++) {
-			this.adjustZone(audioContext, preset.zones[i]);
-		}
-	};
+		const fixedZones = [];
+		for (let zone of preset.zones) {
+			if (zone.keyRangeLow > zone.keyRangeHigh) continue; // pathological case, not used anyway
+			fixedZones.push(zone);
+			this.adjustZone(audioContext, zone);
+		} //loop preset.zones
+		preset.zones = fixedZones;
+		// removing 1-semitone gaps between zones; important for microtones:
+		for (let index = 1; index < preset.zones.length; ++index)
+			preset.zones[index].keyRangeLow = preset.zones[index - 1].keyRangeHigh; 
+	};	
 	this.adjustZone = function (audioContext, zone) {
 		if (zone.buffer) {
 			//
diff --git a/npm/src/player.js b/npm/src/player.js
index 77fdc70..5e3e368 100644
--- a/npm/src/player.js
+++ b/npm/src/player.js
@@ -169,9 +169,16 @@ function WebAudioFontPlayer() {
 		return envelope;
 	};
 	this.adjustPreset = function (audioContext, preset) {
-		for (var i = 0; i < preset.zones.length; i++) {
-			this.adjustZone(audioContext, preset.zones[i]);
-		}
+		const fixedZones = [];
+		for (let zone of preset.zones) {
+			if (zone.keyRangeLow > zone.keyRangeHigh) continue; // pathological case, not used anyway
+			fixedZones.push(zone);
+			this.adjustZone(audioContext, zone);
+		} //loop preset.zones
+		preset.zones = fixedZones;
+		// removing 1-semitone gaps between zones; important for microtones:
+		for (let index = 1; index < preset.zones.length; ++index)
+			preset.zones[index].keyRangeLow = preset.zones[index - 1].keyRangeHigh; 
 	};
 	this.adjustZone = function (audioContext, zone) {
 		if (zone.buffer) {