https://www.youtube.com/watch?v=iFEmdtQmbe0 - Demo in action
This has cubes, spheres, a ground and chains/hinges.
Code: Select all
#include <iostream>
#include <irrlicht.h>
#include <btBulletDynamicsCommon.h>
using namespace irr;
using namespace core;
using namespace video;
using namespace scene;
using namespace io;
using namespace gui;
class InputEventHandler : public IEventReceiver
{
public:
virtual bool OnEvent(const SEvent& event)
{
if (event.EventType == irr::EET_KEY_INPUT_EVENT)
{
KeyIsDown[event.KeyInput.Key] = event.KeyInput.PressedDown;
return false;
}
}
virtual bool IsKeyDown(EKEY_CODE keyCode) const
{
bool ret = KeyIsDown[keyCode];
return ret;
}
virtual void Reset(EKEY_CODE keyCode)
{
KeyIsDown[keyCode] = false;
}
InputEventHandler()
{
for (u32 i = 0; i < KEY_KEY_CODES_COUNT; ++i)
{
KeyIsDown[i] = false;
}
}
private:
bool KeyIsDown[KEY_KEY_CODES_COUNT];
};
btDefaultCollisionConfiguration* collisionConfig;
btCollisionDispatcher* dispatcher;
btBroadphaseInterface* broadphase;
btSequentialImpulseConstraintSolver* solver;
btDiscreteDynamicsWorld* world;
btAlignedObjectArray<btCollisionShape*> collide_shapes;
int lastFPS = -1;
void InitPhysics();
void ExitPhysics();
void StepPhysics(float timeStep);
void PhysicsGround();
void AddBox(ISceneManager* Smgr, IVideoDriver* Driver);
void AddSphere(ISceneManager* Smgr, IVideoDriver* Driver);
void DrawPhysicsObjects();
void addChain(int chainCount, const btVector3& suspensionPoint, ISceneManager* Smgr, IVideoDriver* Driver);
void ShootBox(ISceneManager* Smgr, IVideoDriver* Driver, vector3df& position, vector3df& lookat);
void ShootSphere(ISceneManager* Smgr, IVideoDriver* Driver, vector3df& position, vector3df& lookat);
btBoxShape* createBoxShape(const btVector3& halfExtents)
{
btBoxShape* box = new btBoxShape(halfExtents);
return box;
}
btSphereShape* createSphereShape(btScalar radius)
{
btSphereShape* sphere = new btSphereShape(radius);
return sphere;
}
btRigidBody* createRigidBody(btDiscreteDynamicsWorld* world, float mass, const btTransform& transform, btCollisionShape* shape, const btVector4& color = btVector4(1, 0, 0, 1))
{
btAssert((!shape || shape->getShapeType() != INVALID_SHAPE_PROXYTYPE));
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
shape->calculateLocalInertia(mass, localInertia);
#define USE_MOTIONSTATE 1
#ifdef USE_MOTIONSTATE
btDefaultMotionState* motionState = new btDefaultMotionState(transform);
btRigidBody::btRigidBodyConstructionInfo info(mass, motionState, shape, localInertia);
btRigidBody* body = new btRigidBody(info);
#else
btRigidBody* body = new btRigidBody(mass, 0, shape, localInertia);
#endif
body->setUserIndex(-1);
world->addRigidBody(body);
return body;
}
int main(int argc, char* argv[])
{
InputEventHandler receiver;
IrrlichtDevice* Device = createDevice(video::EDT_DIRECT3D9, dimension2d<u32>(1024, 720), 32, false, false, false, &receiver);
if (!Device)
return 1;
video::IVideoDriver* Driver = Device->getVideoDriver();
scene::ISceneManager* Smgr = Device->getSceneManager();
gui::IGUIEnvironment* Env = Device->getGUIEnvironment();
InitPhysics();
PhysicsGround();
ICameraSceneNode* Camera;
Device->setWindowCaption(L"Irrlicht Bullet Physics");
//The ground
IAnimatedMesh* hillPlaneMesh = Smgr->addHillPlaneMesh("myHill", dimension2d<f32>(30, 30), dimension2d<u32>(10, 10), 0, 0, dimension2d<f32>(0, 0), dimension2d<f32>(10, 10));
ISceneNode* planeNode = Smgr->addAnimatedMeshSceneNode(hillPlaneMesh);
planeNode->setMaterialTexture(0, Driver->getTexture("/media/stones.jpg"));
planeNode->setMaterialFlag(video::EMF_LIGHTING, false);
planeNode->setPosition(core::vector3df(0, -55, 0));
Camera = Smgr->addCameraSceneNodeFPS(NULL, 20.0f, 0.02f);
Camera->setPosition(vector3df(0, 10, -200));
u32 then = Device->getTimer()->getTime();
while (Device->run() && Driver)
{
const u32 now = Device->getTimer()->getTime();
DrawPhysicsObjects();
if (receiver.IsKeyDown(KEY_ESCAPE))
break;
if (receiver.IsKeyDown(KEY_KEY_Z))
{
AddBox(Smgr, Driver);
receiver.Reset(KEY_KEY_Z);
}
if (receiver.IsKeyDown(KEY_KEY_X))
{
AddSphere(Smgr, Driver);
receiver.Reset(KEY_KEY_X);
}
if (receiver.IsKeyDown(KEY_KEY_C))
{
vector3df lookat = Camera->getTarget();
vector3df pose = Camera->getPosition();
ShootBox(Smgr, Driver, pose, (lookat - pose).normalize());
receiver.Reset(KEY_KEY_C);
}
if (receiver.IsKeyDown(KEY_KEY_H))
{
addChain(10, btVector3(10 + (-30 + rand() % 100), 10, 20 + (10 + rand() % 30)), Smgr, Driver);
receiver.Reset(KEY_KEY_H);
}
if (receiver.IsKeyDown(KEY_KEY_V))
{
vector3df lookat = Camera->getTarget();
vector3df pose = Camera->getPosition();
ShootSphere(Smgr, Driver, pose, (lookat - pose).normalize());
receiver.Reset(KEY_KEY_V);
}
Driver->beginScene(true, true, video::SColor(255, 0, 0, 255));
Smgr->drawAll();
Env->drawAll();
Driver->endScene();
int fps = Driver->getFPS();
if (lastFPS != fps)
{
stringw str = L"Irrhct Bullet Physics [";
str += Driver->getName();
str += "] FPS:";
str += fps;
Device->setWindowCaption(str.c_str());
lastFPS = fps;
}
const f32 frameDeltaTime = (f32)(now - then) / 1000.f;
//Step physics
StepPhysics(frameDeltaTime);
then = now;
}
Device->drop();
ExitPhysics();
return 0;
}
void InitPhysics()
{
collisionConfig = new btDefaultCollisionConfiguration();
dispatcher = new btCollisionDispatcher(collisionConfig);
broadphase = new btDbvtBroadphase();
solver = new btSequentialImpulseConstraintSolver();
world = new btDiscreteDynamicsWorld(dispatcher, broadphase, solver, collisionConfig);
world->setGravity(btVector3(0, -10, 0));
}
void PhysicsGround()
{
btCollisionShape* groundShape = new btBoxShape(btVector3(btScalar(150.), btScalar(1.), btScalar(150.)));
collide_shapes.push_back(groundShape);
btTransform transform;
transform.setIdentity();
transform.setOrigin(btVector3(0, -56, 0));
btScalar mass(0.);
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
groundShape->calculateLocalInertia(mass, localInertia);
btDefaultMotionState* motionState = new btDefaultMotionState(transform);
btRigidBody::btRigidBodyConstructionInfo info(mass, motionState, groundShape, localInertia);
btRigidBody* body = new btRigidBody(info);
body->setUserIndex(5);
body->setFriction(1);
world->addRigidBody(body);
}
void AddBox(ISceneManager* Smgr, IVideoDriver* Driver)
{
btCollisionShape* Shape = createBoxShape(btVector3(5, 5, 5));
collide_shapes.push_back(Shape);
btTransform transform;
transform.setIdentity();
btScalar mass(3.f);
transform.setOrigin(btVector3(10, 40, 20));
btQuaternion quat(btVector3(0.4, .02, .1), 67);
transform.setRotation(quat);
btRigidBody* body = createRigidBody(world, mass, transform, Shape);
body->setFriction(1);
body->setUserIndex(10);
IMeshSceneNode* cubeNode = Smgr->addCubeSceneNode(10.0f, NULL, -1, vector3df(0, 3, 10));
cubeNode->setMaterialType(EMT_SOLID);
cubeNode->setMaterialTexture(0, Driver->getTexture("/media/wall.jpg"));
cubeNode->setMaterialFlag(video::EMF_LIGHTING, false);
cubeNode->setVisible(false);
body->setUserPointer(cubeNode);
}
void AddSphere(ISceneManager* Smgr, IVideoDriver* Driver)
{
btCollisionShape* Shape = createSphereShape(btScalar(5));
collide_shapes.push_back(Shape);
btTransform transform;
transform.setIdentity();
btScalar mass(10.f);
transform.setOrigin(btVector3(5, 40, 20));
btQuaternion quat(btVector3(0.4, .02, .1), 67);
transform.setRotation(quat);
btRigidBody* body = createRigidBody(world, mass, transform, Shape);
body->setFriction(2);
body->setUserIndex(10);
IMeshSceneNode* sphereNode = Smgr->addSphereSceneNode(10.0f, 32);
sphereNode->setMaterialType(EMT_SOLID);
sphereNode->setMaterialTexture(0, Driver->getTexture("/media/water.jpg"));
sphereNode->setMaterialFlag(video::EMF_LIGHTING, false);
sphereNode->setVisible(false);
body->setUserPointer(sphereNode);
}
void addChain(int chainCount, const btVector3& suspensionPoint, ISceneManager* Smgr, IVideoDriver* Driver)
{
btBoxShape* Shape = createBoxShape(btVector3(4, 4, 1));
collide_shapes.push_back(Shape);
btTransform transform;
transform.setIdentity();
btScalar mass(1.f);
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
Shape->calculateLocalInertia(mass, localInertia);
btAlignedObjectArray<btRigidBody*> boxes;
int lastBox = chainCount - 1;
for (int i = 0; i < chainCount; ++i)
{
transform.setOrigin(btVector3(btScalar(suspensionPoint.x()), btScalar(suspensionPoint.y() + i * 2), btScalar(suspensionPoint.z())));
boxes.push_back(createRigidBody(world, (i == lastBox) ? 0 : mass, transform, Shape));
IMeshSceneNode* Node = Smgr->addCubeSceneNode(8.0f, NULL, -1, vector3df(0, 0, 0), vector3df(0, 0, 0), vector3df(1, 1, 0.25f));
Node->setMaterialType(EMT_SOLID);
Node->setMaterialTexture(0, Driver->getTexture("/media/wall.jpg"));
Node->setMaterialFlag(video::EMF_LIGHTING, false);
boxes[i]->setUserPointer(Node);
}
for (int i = 0; i < chainCount - 1; ++i)
{
btRigidBody* b1 = boxes[i];
btRigidBody* b2 = boxes[i + 1];
btPoint2PointConstraint* leftSpring = new btPoint2PointConstraint(*b1, *b2, btVector3(-2, 4, 0), btVector3(-2, -4,0));
world->addConstraint(leftSpring);
btPoint2PointConstraint* rightSpring = new btPoint2PointConstraint(*b1, *b2, btVector3(2, 4, 0), btVector3(2, -4, 0));
world->addConstraint(rightSpring);
}
}
void ShootBox(ISceneManager* Smgr, IVideoDriver* Driver, vector3df& position, vector3df& lookat)
{
btCollisionShape* Shape = new btBoxShape(btVector3(5, 5, 5));
collide_shapes.push_back(Shape);
btTransform transform;
transform.setIdentity();
btScalar mass(6.f);
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
Shape->calculateLocalInertia(mass, localInertia);
transform.setOrigin(btVector3(position.X, position.Y, position.Z));
btQuaternion quat(btVector3(0.4, .02, .1), 67);
transform.setRotation(quat);
btDefaultMotionState* motionState = new btDefaultMotionState(transform);
btRigidBody::btRigidBodyConstructionInfo info(mass, motionState, Shape, localInertia);
btRigidBody* body = new btRigidBody(info);
body->setUserIndex(10);
body->setDamping(0.01, 0.01);
ISceneNode* Node = Smgr->addCubeSceneNode(10.0f, NULL, -1, vector3df(0, 3, 10));
Node->setMaterialType(EMT_SOLID);
Node->setMaterialTexture(0, Driver->getTexture("/media/wall.jpg"));
Node->setMaterialFlag(video::EMF_LIGHTING, false);
Node->setVisible(false);
body->setUserPointer(Node);
body->setFriction(1);
btVector3 force(lookat.X, lookat.Y, lookat.Z);
world->addRigidBody(body);
body->applyImpulse(250 * force, btVector3(0., 0., 0.0));
}
void ShootSphere(ISceneManager* Smgr, IVideoDriver* Driver, vector3df& position, vector3df& lookat)
{
btCollisionShape* Shape = createSphereShape(btScalar(5));
collide_shapes.push_back(Shape);
btTransform transform;
transform.setIdentity();
btScalar mass(6.f);
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
Shape->calculateLocalInertia(mass, localInertia);
transform.setOrigin(btVector3(position.X, position.Y, position.Z));
btQuaternion quat(btVector3(0.4, .02, .1), 67);
transform.setRotation(quat);
btDefaultMotionState* motionState = new btDefaultMotionState(transform);
btRigidBody::btRigidBodyConstructionInfo info(mass, motionState, Shape, localInertia);
btRigidBody* body = new btRigidBody(info);
body->setUserIndex(10);
body->setDamping(0.01, 0.01);
IMeshSceneNode* sphereNode = Smgr->addSphereSceneNode(10.0f, 32);
sphereNode->setMaterialType(EMT_SOLID);
sphereNode->setMaterialTexture(0, Driver->getTexture("/media/water.jpg"));
sphereNode->setMaterialFlag(video::EMF_LIGHTING, false);
sphereNode->setVisible(false);
body->setUserPointer(sphereNode);
body->setFriction(1);
btVector3 force(lookat.X, lookat.Y, lookat.Z);
world->addRigidBody(body);
body->applyImpulse(350 * force, btVector3(0., 0., 0.0));
}
void DrawPhysicsObjects()
{
int numObjects = world->getNumCollisionObjects();
for (int j = numObjects - 1; j >= 0; j--)
{
btCollisionObject* obj = world->getCollisionObjectArray()[j];
btRigidBody* body = btRigidBody::upcast(obj);
btTransform trans;
if (body && body->getMotionState())
{
body->getMotionState()->getWorldTransform(trans);
ISceneNode* cube = reinterpret_cast<ISceneNode*>(body->getUserPointer());
if (cube != NULL)
{
btVector3 origin = trans.getOrigin();
btQuaternion rot = trans.getRotation();
quaternion q(rot.getX(), rot.getY(), rot.getZ(), rot.getW());
vector3df Euler;
q.toEuler(Euler);
Euler *= RADTODEG;
cube->setPosition(vector3df(origin.getX(), origin.getY(), origin.getZ()));
cube->setRotation(Euler);
cube->setVisible(true);
}
}
else
{
trans = obj->getWorldTransform();
}
}
}
void StepPhysics(float timeStep)
{
world->stepSimulation(timeStep * 2, 10);
}
void ExitPhysics()
{
int i;
for (i = world->getNumConstraints() - 1; i >= 0; i--)
{
world->removeConstraint(world->getConstraint(i));
}
for (i = world->getNumCollisionObjects() - 1; i >= 0; i--)
{
btCollisionObject* obj = world->getCollisionObjectArray()[i];
btRigidBody* body = btRigidBody::upcast(obj);
if (body && body->getMotionState())
{
delete body->getMotionState();
}
world->removeCollisionObject(obj);
delete obj;
}
for (int j = 0; j < collide_shapes.size(); j++)
{
btCollisionShape* shape = collide_shapes[j];
collide_shapes[j] = 0;
delete shape;
}
delete world;
delete solver;
delete broadphase;
delete dispatcher;
delete collisionConfig;
collide_shapes.clear();
}