From dc96bdda851d9b5bd9b8c6c17d5aacd4044ba3a0 Mon Sep 17 00:00:00 2001
From: Jeffrey Pfau <jeffrey@endrift.com>
Date: Wed, 11 Jan 2017 03:31:50 -0800
Subject: [PATCH] GB Audio: Start implementing "zombie" audio (fixes #389)

---
 CHANGES        | 1 +
 src/gb/audio.c | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/CHANGES b/CHANGES
index b133538f8..cd88ab172 100644
--- a/CHANGES
+++ b/CHANGES
@@ -44,6 +44,7 @@ Misc:
  - Qt: Improved HiDPI support
  - Qt: Expose configuration directory
  - Feature: Move game database from flatfile to SQLite3
+ - GB Audio: Start implementing "zombie" audio (fixes mgba.io/i/389)
 
 0.5.2: (2016-12-31)
 Bugfixes:
diff --git a/src/gb/audio.c b/src/gb/audio.c
index 183927730..17f00351d 100644
--- a/src/gb/audio.c
+++ b/src/gb/audio.c
@@ -698,6 +698,10 @@ bool _writeEnvelope(struct GBAudioEnvelope* envelope, uint8_t value) {
 	envelope->stepTime = GBAudioRegisterSweepGetStepTime(value);
 	envelope->direction = GBAudioRegisterSweepGetDirection(value);
 	envelope->initialVolume = GBAudioRegisterSweepGetInitialVolume(value);
+	if (!envelope->stepTime) {
+		// TODO: Improve "zombie" mode
+		++envelope->currentVolume;
+	}
 	_updateEnvelopeDead(envelope);
 	envelope->nextStep = envelope->stepTime;
 	return (envelope->initialVolume || envelope->direction) && envelope->dead != 2;