Add the old Bullet 2.x obsolete demos, and CMake buildsystem files, and gradually move them to newer Bullet 3.x structure

Use statically linked freeglut, instead of dynamic glut for the obsolete Bullet 2.x demos
Add the 'reset' method to b3GpuDynamicsWorld, and use it in the BasicGpuDemo (pretty slow in debug mode, use release mode)
Don't crash in btCollisionWorld, if there is no collision dispatcher

ObsoleteDemos/BasicDemo/BasicDemo.cpp

@@ -0,0 +1,273 @@
+/*
+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.
+*/
+
+
+///create 125 (5x5x5) dynamic object
+#define ARRAY_SIZE_X 10
+#define ARRAY_SIZE_Y 10
+#define ARRAY_SIZE_Z 10
+
+//maximum number of objects (and allow user to shoot additional boxes)
+#define MAX_PROXIES (ARRAY_SIZE_X*ARRAY_SIZE_Y*ARRAY_SIZE_Z + 1024)
+
+///scaling of the objects (0.1 = 20 centimeter boxes )
+#define SCALING 1.
+#define START_POS_X -5
+#define START_POS_Y -5
+#define START_POS_Z -3
+
+#include "BasicDemo.h"
+#include "GlutStuff.h"
+///btBulletDynamicsCommon.h is the main Bullet include file, contains most common include files.
+#include "btBulletDynamicsCommon.h"
+
+#include <stdio.h> //printf debugging
+#include "GLDebugDrawer.h"
+#include "LinearMath/btAabbUtil2.h"
+
+static GLDebugDrawer gDebugDraw;
+
+///The MyOverlapCallback is used to show how to collect object that overlap with a given bounding box defined by aabbMin and aabbMax. 
+///See m_dynamicsWorld->getBroadphase()->aabbTest.
+struct	MyOverlapCallback : public btBroadphaseAabbCallback
+{
+	btVector3 m_queryAabbMin;
+	btVector3 m_queryAabbMax;
+	
+	int m_numOverlap;
+	MyOverlapCallback(const btVector3& aabbMin, const btVector3& aabbMax ) : m_queryAabbMin(aabbMin),m_queryAabbMax(aabbMax),m_numOverlap(0)	{}
+	virtual bool	process(const btBroadphaseProxy* proxy)
+	{
+		btVector3 proxyAabbMin,proxyAabbMax;
+		btCollisionObject* colObj0 = (btCollisionObject*)proxy->m_clientObject;
+		colObj0->getCollisionShape()->getAabb(colObj0->getWorldTransform(),proxyAabbMin,proxyAabbMax);
+		if (TestAabbAgainstAabb2(proxyAabbMin,proxyAabbMax,m_queryAabbMin,m_queryAabbMax))
+		{
+			m_numOverlap++;
+		}
+		return true;
+	}
+};
+
+void BasicDemo::clientMoveAndDisplay()
+{
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
+
+	//simple dynamics world doesn't handle fixed-time-stepping
+	float ms = getDeltaTimeMicroseconds();
+	
+	///step the simulation
+	if (m_dynamicsWorld)
+	{
+		m_dynamicsWorld->stepSimulation(ms / 1000000.f);
+		//optional but useful: debug drawing
+		m_dynamicsWorld->debugDrawWorld();
+
+		btVector3 aabbMin(1,1,1);
+		btVector3 aabbMax(2,2,2);
+
+		MyOverlapCallback aabbOverlap(aabbMin,aabbMax);
+		m_dynamicsWorld->getBroadphase()->aabbTest(aabbMin,aabbMax,aabbOverlap);
+		
+		if (aabbOverlap.m_numOverlap)
+			printf("#aabb overlap = %d\n", aabbOverlap.m_numOverlap);
+	}
+		
+	renderme(); 
+
+	glFlush();
+
+	swapBuffers();
+
+}
+
+
+
+void BasicDemo::displayCallback(void) {
+
+	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
+	
+	renderme();
+
+	//optional but useful: debug drawing to detect problems
+	if (m_dynamicsWorld)
+		m_dynamicsWorld->debugDrawWorld();
+
+	glFlush();
+	swapBuffers();
+}
+
+
+
+
+
+void	BasicDemo::initPhysics()
+{
+	setTexturing(true);
+	setShadows(true);
+
+	setCameraDistance(btScalar(SCALING*50.));
+
+	///collision configuration contains default setup for memory, collision setup
+	m_collisionConfiguration = new btDefaultCollisionConfiguration();
+	//m_collisionConfiguration->setConvexConvexMultipointIterations();
+
+	///use the default collision dispatcher. For parallel processing you can use a diffent dispatcher (see Extras/BulletMultiThreaded)
+	m_dispatcher = new	btCollisionDispatcher(m_collisionConfiguration);
+
+	m_broadphase = new btDbvtBroadphase();
+
+	///the default constraint solver. For parallel processing you can use a different solver (see Extras/BulletMultiThreaded)
+	btSequentialImpulseConstraintSolver* sol = new btSequentialImpulseConstraintSolver;
+	m_solver = sol;
+
+	m_dynamicsWorld = new btDiscreteDynamicsWorld(m_dispatcher,m_broadphase,m_solver,m_collisionConfiguration);
+	m_dynamicsWorld->setDebugDrawer(&gDebugDraw);
+	
+	m_dynamicsWorld->setGravity(btVector3(0,-10,0));
+
+	///create a few basic rigid bodies
+	btBoxShape* groundShape = new btBoxShape(btVector3(btScalar(50.),btScalar(50.),btScalar(50.)));
+	//groundShape->initializePolyhedralFeatures();
+//	btCollisionShape* groundShape = new btStaticPlaneShape(btVector3(0,1,0),50);
+	
+	m_collisionShapes.push_back(groundShape);
+
+	btTransform groundTransform;
+	groundTransform.setIdentity();
+	groundTransform.setOrigin(btVector3(0,-50,0));
+
+	//We can also use DemoApplication::localCreateRigidBody, but for clarity it is provided here:
+	{
+		btScalar mass(0.);
+
+		//rigidbody is dynamic if and only if mass is non zero, otherwise static
+		bool isDynamic = (mass != 0.f);
+
+		btVector3 localInertia(0,0,0);
+		if (isDynamic)
+			groundShape->calculateLocalInertia(mass,localInertia);
+
+		//using motionstate is recommended, it provides interpolation capabilities, and only synchronizes 'active' objects
+		btDefaultMotionState* myMotionState = new btDefaultMotionState(groundTransform);
+		btRigidBody::btRigidBodyConstructionInfo rbInfo(mass,myMotionState,groundShape,localInertia);
+		btRigidBody* body = new btRigidBody(rbInfo);
+
+		//add the body to the dynamics world
+		m_dynamicsWorld->addRigidBody(body);
+	}
+
+
+	{
+		//create a few dynamic rigidbodies
+		// Re-using the same collision is better for memory usage and performance
+
+		btBoxShape* colShape = new btBoxShape(btVector3(SCALING*1,SCALING*1,SCALING*1));
+		//btCollisionShape* colShape = new btSphereShape(btScalar(1.));
+		m_collisionShapes.push_back(colShape);
+
+		/// Create Dynamic Objects
+		btTransform startTransform;
+		startTransform.setIdentity();
+
+		btScalar	mass(1.f);
+
+		//rigidbody is dynamic if and only if mass is non zero, otherwise static
+		bool isDynamic = (mass != 0.f);
+
+		btVector3 localInertia(0,0,0);
+		if (isDynamic)
+			colShape->calculateLocalInertia(mass,localInertia);
+
+		float start_x = START_POS_X - ARRAY_SIZE_X/2;
+		float start_y = START_POS_Y;
+		float start_z = START_POS_Z - ARRAY_SIZE_Z/2;
+
+		for (int k=0;k<ARRAY_SIZE_Y;k++)
+		{
+			for (int i=0;i<ARRAY_SIZE_X;i++)
+			{
+				for(int j = 0;j<ARRAY_SIZE_Z;j++)
+				{
+					startTransform.setOrigin(SCALING*btVector3(
+										btScalar(2.0*i + start_x),
+										btScalar(20+2.0*k + start_y),
+										btScalar(2.0*j + start_z)));
+
+			
+					//using motionstate is recommended, it provides interpolation capabilities, and only synchronizes 'active' objects
+					btDefaultMotionState* myMotionState = new btDefaultMotionState(startTransform);
+					btRigidBody::btRigidBodyConstructionInfo rbInfo(mass,myMotionState,colShape,localInertia);
+					btRigidBody* body = new btRigidBody(rbInfo);
+					
+
+					m_dynamicsWorld->addRigidBody(body);
+				}
+			}
+		}
+	}
+
+
+}
+void	BasicDemo::clientResetScene()
+{
+	exitPhysics();
+	initPhysics();
+}
+	
+
+void	BasicDemo::exitPhysics()
+{
+
+	//cleanup in the reverse order of creation/initialization
+
+	//remove the rigidbodies from the dynamics world and delete them
+	int i;
+	for (i=m_dynamicsWorld->getNumCollisionObjects()-1; i>=0 ;i--)
+	{
+		btCollisionObject* obj = m_dynamicsWorld->getCollisionObjectArray()[i];
+		btRigidBody* body = btRigidBody::upcast(obj);
+		if (body && body->getMotionState())
+		{
+			delete body->getMotionState();
+		}
+		m_dynamicsWorld->removeCollisionObject( obj );
+		delete obj;
+	}
+
+	//delete collision shapes
+	for (int j=0;j<m_collisionShapes.size();j++)
+	{
+		btCollisionShape* shape = m_collisionShapes[j];
+		delete shape;
+	}
+	m_collisionShapes.clear();
+
+	delete m_dynamicsWorld;
+	
+	delete m_solver;
+	
+	delete m_broadphase;
+	
+	delete m_dispatcher;
+
+	delete m_collisionConfiguration;
+
+	
+}
+
+
+
+