From 10b3e7fc676736c46aafa354065bd6a879cfda8c Mon Sep 17 00:00:00 2001
From: Andrew Meadows <andrew@highfidelity.io>
Date: Mon, 6 Mar 2017 15:14:51 -0800
Subject: [PATCH] sphere shapeType for models means 'sphere'

---
 libraries/entities/src/ShapeEntityItem.cpp |  2 +-
 libraries/physics/src/ShapeFactory.cpp     | 13 ++++++++++++-
 libraries/shared/src/ShapeInfo.h           |  3 ++-
 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/libraries/entities/src/ShapeEntityItem.cpp b/libraries/entities/src/ShapeEntityItem.cpp
index eaef4c5c0e..345d9e54ab 100644
--- a/libraries/entities/src/ShapeEntityItem.cpp
+++ b/libraries/entities/src/ShapeEntityItem.cpp
@@ -163,7 +163,7 @@ void ShapeEntityItem::appendSubclassData(OctreePacketData* packetData, EncodeBit
 // This value specifes how the shape should be treated by physics calculations.  
 // For now, all polys will act as spheres
 ShapeType ShapeEntityItem::getShapeType() const {
-    return (_shape == entity::Shape::Cube) ? SHAPE_TYPE_BOX : SHAPE_TYPE_SPHERE;
+    return (_shape == entity::Shape::Cube) ? SHAPE_TYPE_BOX : SHAPE_TYPE_ELLIPSOID;
 }
 
 void ShapeEntityItem::setColor(const rgbColor& value) {
diff --git a/libraries/physics/src/ShapeFactory.cpp b/libraries/physics/src/ShapeFactory.cpp
index 100dab0fd1..560b0a6db2 100644
--- a/libraries/physics/src/ShapeFactory.cpp
+++ b/libraries/physics/src/ShapeFactory.cpp
@@ -256,9 +256,20 @@ const btCollisionShape* ShapeFactory::createShapeFromInfo(const ShapeInfo& info)
         }
         break;
         case SHAPE_TYPE_SPHERE: {
+            glm::vec3 halfExtents = info.getHalfExtents();
+            float radius = glm::max(halfExtents.x, glm::max(halfExtents.y, halfExtents.z));
+            shape = new btSphereShape(radius);
+        }
+        break;
+        case SHAPE_TYPE_ELLIPSOID: {
             glm::vec3 halfExtents = info.getHalfExtents();
             float radius = halfExtents.x;
-            if (radius == halfExtents.y && radius == halfExtents.z) {
+            const float MIN_RADIUS = 0.001f;
+            const float MIN_RELATIVE_SPHERICAL_ERROR = 0.001f;
+            if (radius > MIN_RADIUS
+                    && fabs(radius - halfExtents.y) / radius < MIN_RELATIVE_SPHERICAL_ERROR
+                    && fabs(radius - halfExtents.z) / radius < MIN_RELATIVE_SPHERICAL_ERROR) {
+                // close enough to true sphere
                 shape = new btSphereShape(radius);
             } else {
                 ShapeInfo::PointList points;
diff --git a/libraries/shared/src/ShapeInfo.h b/libraries/shared/src/ShapeInfo.h
index a6ff8d6d4a..98b397ee16 100644
--- a/libraries/shared/src/ShapeInfo.h
+++ b/libraries/shared/src/ShapeInfo.h
@@ -45,7 +45,8 @@ enum ShapeType {
     SHAPE_TYPE_COMPOUND,
     SHAPE_TYPE_SIMPLE_HULL,
     SHAPE_TYPE_SIMPLE_COMPOUND,
-    SHAPE_TYPE_STATIC_MESH
+    SHAPE_TYPE_STATIC_MESH,
+    SHAPE_TYPE_ELLIPSOID
 };
 
 class ShapeInfo {