From 2c3d74bc23947a998fa1f330c5ab025804866c99 Mon Sep 17 00:00:00 2001
From: David Thompson <dthompson2@worcester.edu>
Date: Thu, 27 Apr 2017 22:17:50 -0400
Subject: math: Add lerp procedure.

* chickadee/math.scm (lerp): New procedure.
---
 chickadee/math.scm | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/chickadee/math.scm b/chickadee/math.scm
index adb7d8b..e9ebc6d 100644
--- a/chickadee/math.scm
+++ b/chickadee/math.scm
@@ -21,7 +21,8 @@
             square
             clamp
             min
-            max)
+            max
+            lerp)
   #:replace (min max))
 
 (define pi 3.14159265358979323846)
@@ -55,3 +56,7 @@ actually less than MAX."
     ((_ a b ...)
      (let ((m (max b ...)))
        (if (> a m) a m)))))
+
+(define-inlinable (lerp start end alpha)
+  (+ (* start (- 1.0 alpha))
+     (* end alpha)))
-- 
cgit v1.2.3