From 82ce34dea3b9230e42fe2fe9e2562d1f2b85d699 Mon Sep 17 00:00:00 2001
From: Ahmet Inan <inan@aicodix.de>
Date: Fri, 7 May 2021 17:18:06 +0200
Subject: [PATCH] use well known order of lerp arguments

---
 amd.hh   | 2 +-
 ema.hh   | 4 ++--
 utils.hh | 4 ++--
 3 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/amd.hh b/amd.hh
index 1048686..c310ffa 100644
--- a/amd.hh
+++ b/amd.hh
@@ -32,7 +32,7 @@ public:
 	value_type operator()(complex_type input)
 	{
 		value_type amp = abs(input);
-		avg = lerp(amp < avg ? dec : att, avg, amp);
+		avg = lerp(avg, amp, amp < avg ? dec : att);
 		avg = min(max(avg, lo), hi);
 		amp /= avg;
 		return (amp * (value_type(1)+idx) - value_type(1)) / idx;
diff --git a/ema.hh b/ema.hh
index 4a23a4d..fd86ddd 100644
--- a/ema.hh
+++ b/ema.hh
@@ -35,7 +35,7 @@ public:
 	}
 	TYPE operator()(TYPE input)
 	{
-		return prev = lerp(alpha, prev, input);
+		return prev = lerp(prev, input, alpha);
 	}
 };
 
@@ -83,7 +83,7 @@ public:
 	TYPE operator()(TYPE input)
 	{
 		for (int i = 0; i < ORDER; ++i)
-			prev[i] = input = lerp(alpha, prev[i], input);
+			prev[i] = input = lerp(prev[i], input, alpha);
 		return input;
 	}
 };
diff --git a/utils.hh b/utils.hh
index 8a004e5..4ba2d79 100644
--- a/utils.hh
+++ b/utils.hh
@@ -16,8 +16,8 @@ int signum(TYPE v)
 	return (v > TYPE(0)) - (v < TYPE(0));
 }
 
-template <typename X, typename AB>
-AB lerp(X x, AB a, AB b)
+template <typename AB, typename X>
+AB lerp(AB a, AB b, X x)
 {
 	return (X(1) - x) * a + x * b;
 }