From b8bfe325a029fe78372df7198cf33d8657f4b9f9 Mon Sep 17 00:00:00 2001
From: Stephen Birarda <commit@birarda.com>
Date: Wed, 9 Apr 2014 10:03:26 -0700
Subject: [PATCH] add back code blow away in regex replacements

---
 interface/src/Physics.cpp | 26 ++++++++++++++++++++++++--
 1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/interface/src/Physics.cpp b/interface/src/Physics.cpp
index a9f9f6b17d..30ea829c4e 100644
--- a/interface/src/Physics.cpp
+++ b/interface/src/Physics.cpp
@@ -8,6 +8,29 @@
 //  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
 //
 
+#include <glm/glm.hpp>
+#include <SharedUtil.h>
+
+#include "Util.h"
+#include "world.h"
+#include "Physics.h"
+
+//
+//  Applies static friction:  maxVelocity is the largest velocity for which there
+//  there is friction, and strength is the amount of friction force applied to reduce
+//  velocity. 
+// 
+void applyStaticFriction(float deltaTime, glm::vec3& velocity, float maxVelocity, float strength) {
+    float v = glm::length(velocity);
+    if (v < maxVelocity) {
+        velocity *= glm::clamp((1.0f - deltaTime * strength * (1.f - v / maxVelocity)), 0.0f, 1.0f);
+    }
+}
+
+//
+//  Applies velocity damping, with a strength value for linear and squared velocity damping
+//
+
 void applyDamping(float deltaTime, glm::vec3& velocity, float linearStrength, float squaredStrength) {
     if (squaredStrength == 0.f) {
         velocity *= glm::clamp(1.f - deltaTime * linearStrength, 0.f, 1.f);
@@ -18,5 +41,4 @@ void applyDamping(float deltaTime, glm::vec3& velocity, float linearStrength, fl
 
 void applyDampedSpring(float deltaTime, glm::vec3& velocity, glm::vec3& position, glm::vec3& targetPosition, float k, float damping) {
     
-}
-
+}
\ No newline at end of file