diff --git a/include/engine.hpp b/include/engine.hpp
index ce7d43d0..cfff9b1d 100644
--- a/include/engine.hpp
+++ b/include/engine.hpp
@@ -30,8 +30,9 @@ struct Output {
 };
 
 struct Light {
+	/** The square of the brightness value */
 	float value = 0.0;
-	void setSmooth(float v);
+	void setBrightnessSmooth(float brightness);
 };
 
 
diff --git a/src/engine.cpp b/src/engine.cpp
index f34ca99e..ef0163dd 100644
--- a/src/engine.cpp
+++ b/src/engine.cpp
@@ -33,8 +33,8 @@ static int smoothParamId;
 static float smoothValue;
 
 
-void Light::setSmooth(float v) {
-	value += (v - value) / sampleRate * 60.0;
+void Light::setBrightnessSmooth(float brightness) {
+	value += (powf(brightness, 2) - value) / sampleRate * 60.0;
 }