From 149ecac9d3d8fc923ecb008b6749a82670907744 Mon Sep 17 00:00:00 2001
From: Andrew Belt <andrewpbelt@gmail.com>
Date: Thu, 26 Oct 2017 10:19:43 -0400
Subject: [PATCH] Added engineGetSampleTime()

---
 include/engine.hpp |  2 ++
 src/engine.cpp     | 13 +++++++++----
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/include/engine.hpp b/include/engine.hpp
index c5a14354..1496f0d6 100644
--- a/include/engine.hpp
+++ b/include/engine.hpp
@@ -97,6 +97,8 @@ void engineSetParam(Module *module, int paramId, float value);
 void engineSetParamSmooth(Module *module, int paramId, float value);
 void engineSetSampleRate(float sampleRate);
 float engineGetSampleRate();
+/** Returns the inverse of the current sample rate */
+float engineGetSampleTime();
 
 extern bool gPaused;
 
diff --git a/src/engine.cpp b/src/engine.cpp
index e064947b..bf903cda 100644
--- a/src/engine.cpp
+++ b/src/engine.cpp
@@ -14,7 +14,8 @@
 
 namespace rack {
 
-float sampleRate = 0.0;
+float sampleRate;
+float sampleTime;
 bool gPaused = false;
 
 
@@ -38,7 +39,7 @@ float Light::getBrightness() {
 }
 
 void Light::setBrightnessSmooth(float brightness) {
-	value += (brightness * brightness - value) / sampleRate * 60.0;
+	value += (brightness * brightness - value) * sampleTime * 60.0;
 }
 
 
@@ -70,7 +71,7 @@ static void engineStep() {
 			smoothModule = NULL;
 		}
 		else {
-			value += delta * lambda / sampleRate;
+			value += delta * lambda * sampleTime;
 			smoothModule->params[smoothParamId].value = value;
 		}
 	}
@@ -107,7 +108,7 @@ static void engineRun() {
 			}
 		}
 
-		double stepTime = mutexSteps / sampleRate;
+		double stepTime = mutexSteps * sampleTime;
 		ahead += stepTime;
 		auto currTime = std::chrono::high_resolution_clock::now();
 		const double aheadFactor = 2.0;
@@ -232,6 +233,7 @@ void engineSetSampleRate(float newSampleRate) {
 	VIPLock vipLock(vipMutex);
 	std::lock_guard<std::mutex> lock(mutex);
 	sampleRate = newSampleRate;
+	sampleTime = 1.0 / sampleRate;
 	// onSampleRateChange
 	for (Module *module : modules) {
 		module->onSampleRateChange();
@@ -242,5 +244,8 @@ float engineGetSampleRate() {
 	return sampleRate;
 }
 
+float engineGetSampleTime() {
+	return sampleTime;
+}
 
 } // namespace rack