Added btCapsuleShape. This could already be simulated by simply adding 2 spheres to the btMultiSphereShape, but this was bad documented/unknown.

For tapered capsules, you can still use btMultiSphereShape, just pass 2 spheres with different radius.

src/BulletCollision/CollisionShapes/btCapsuleShape.h

@@ -0,0 +1,60 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+#ifndef BT_CAPSULE_SHAPE_H
+#define BT_CAPSULE_SHAPE_H
+
+#include "btConvexShape.h"
+#include "../BroadphaseCollision/btBroadphaseProxy.h" // for the types
+
+
+///btCapsuleShape represents a capsule around the Y axis
+///A more general solution that can represent capsules is the btMultiSphereShape
+class btCapsuleShape : public btConvexShape
+{
+
+public:
+	btCapsuleShape(float radius,float height);
+
+	///CollisionShape Interface
+	virtual void	calculateLocalInertia(btScalar mass,btVector3& inertia);
+
+	/// btConvexShape Interface
+	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;
+
+	virtual void	batchedUnitVectorGetSupportingVertexWithoutMargin(const btVector3* vectors,btVector3* supportVerticesOut,int numVectors) const;
+	
+	virtual int	getShapeType() const { return CAPSULE_SHAPE_PROXYTYPE; }
+
+	virtual char*	getName()const 
+	{
+		return "CapsuleShape";
+	}
+
+	float	getRadius() const
+	{
+		return m_implicitShapeDimensions.getX();
+	}
+
+	float	getHalfHeight() const
+	{
+		return m_implicitShapeDimensions.getY();
+	}
+
+};
+
+
+
+#endif //BT_CAPSULE_SHAPE_H