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作業中のプロジェクトでjBulletを使用する方法を学習しようとしています。ソースが提供するデモを確認しましたが、これらのデモでオブジェクトがどのように表示されるかを理解できません。誰かが私を指摘したり、画面に1つまたは2つのオブジェクトを表示する基本的な例を提供したりできる優れたリソースを持っていますか？

よろしくお願いします。コードがないので、必要に応じてすぐに書き込めますが、方向性を探しています。

ありがとうございました、

使用しているキューブのコードなので、衝突を追加しようとしていますが、jbulletの使用方法がわかりません。

    public void  Draw() {
    // center point posX, posY, posZ
    float radius = size / 2;

    //top
    glPushMatrix();
    glBegin(GL_QUADS);
        {
            glColor3f(1.0f,0.0f,0.0f); // red
            glVertex3f(posX + radius, posY + radius, posZ - radius);
            glVertex3f(posX - radius, posY + radius, posZ - radius);
            glVertex3f(posX - radius, posY + radius, posZ + radius);
            glVertex3f(posX + radius, posY + radius, posZ + radius);
        }
    glEnd();
    glPopMatrix();

    //bottom
    glPushMatrix();
    glBegin(GL_QUADS);
        {
            glColor3f(1.0f,1.0f,0.0f); // ?? color
            glVertex3f(posX + radius, posY - radius, posZ + radius);
            glVertex3f(posX - radius, posY - radius, posZ + radius);
            glVertex3f(posX - radius, posY - radius, posZ - radius);
            glVertex3f(posX + radius, posY - radius, posZ - radius);
        }
    glEnd();
    glPopMatrix();

    //right side
    glPushMatrix();
    glBegin(GL_QUADS);
        {
            glColor3f(1.0f,0.0f,1.0f); // ?? color
            glVertex3f(posX + radius, posY + radius, posZ + radius);
            glVertex3f(posX + radius, posY - radius, posZ + radius);
            glVertex3f(posX + radius, posY - radius, posZ - radius);
            glVertex3f(posX + radius, posY + radius, posZ - radius);
        }
    glEnd();
    glPopMatrix();

    //left side
    glPushMatrix();
    glBegin(GL_QUADS);
        {
            glColor3f(0.0f,1.0f,1.0f); // ?? color
            glVertex3f(posX - radius, posY + radius, posZ - radius);
            glVertex3f(posX - radius, posY - radius, posZ - radius);
            glVertex3f(posX - radius, posY - radius, posZ + radius);
            glVertex3f(posX - radius, posY + radius, posZ + radius);
        }
    glEnd();
    glPopMatrix();

    //front side 
    glPushMatrix();
    glBegin(GL_QUADS);
        {
            glColor3f(0.0f,0.0f,1.0f); //blue 
            glVertex3f(posX + radius, posY + radius, posZ + radius);
            glVertex3f(posX - radius, posY + radius, posZ + radius);
            glVertex3f(posX - radius, posY - radius, posZ + radius);
            glVertex3f(posX + radius, posY - radius, posZ + radius);
        }
    glEnd();
    glPopMatrix();

    //back side
    glPushMatrix();
    glBegin(GL_QUADS);
        {
            glColor3f(0.0f,1.0f,0.0f); // green
            glVertex3f(posX + radius, posY - radius, posZ - radius);
            glVertex3f(posX - radius, posY - radius, posZ - radius);
            glVertex3f(posX - radius, posY + radius, posZ - radius);
            glVertex3f(posX + radius, posY + radius, posZ - radius);
        }
    glEnd();
    glPopMatrix();
}

これがhelloworldテストコードから変換されたコードですが、これは誰にとっても正しいように見えますか？：

public static void HelloWorld() {

    BroadphaseInterface broadphase = new DbvtBroadphase();
    DefaultCollisionConfiguration collisionConfiguration = new DefaultCollisionConfiguration();
    CollisionDispatcher dispatcher = new CollisionDispatcher(collisionConfiguration);

    SequentialImpulseConstraintSolver solver = new SequentialImpulseConstraintSolver();

    DiscreteDynamicsWorld dynamicsWorld = new DiscreteDynamicsWorld(dispatcher, broadphase, solver, collisionConfiguration);

    // set the gravity of our world
    dynamicsWorld.setGravity(new Vector3f(0, -10, 0));

    // setup our collision shapes
    CollisionShape groundShape = new StaticPlaneShape(new Vector3f(0, 1, 0), 1);
    CollisionShape fallShape = new SphereShape(1);

    // setup the motion state
    DefaultMotionState groundMotionState = new DefaultMotionState(new Transform(new Matrix4f(new Quat4f(0, 0, 0, 1), new Vector3f(0, -1, 0), 1.0f))); 

    RigidBodyConstructionInfo groundRigidBodyCI = new RigidBodyConstructionInfo(0, groundMotionState, groundShape, new Vector3f(0,0,0)); 
    RigidBody groundRigidBody = new RigidBody(groundRigidBodyCI); 

    dynamicsWorld.addRigidBody(groundRigidBody); // add our ground to the dynamic world.. 

    // setup the motion state for the ball
    DefaultMotionState fallMotionState = new DefaultMotionState(new Transform(new Matrix4f(new Quat4f(0, 0, 0, 1), new Vector3f(0, 50, 0), 1.0f)));

    //This we're going to give mass so it responds to gravity 
    int mass = 1;

    Vector3f fallInertia = new Vector3f(0,0,0); 
    fallShape.calculateLocalInertia(mass,fallInertia); 

    RigidBodyConstructionInfo fallRigidBodyCI = new RigidBodyConstructionInfo(mass,fallMotionState,fallShape,fallInertia); 
    RigidBody fallRigidBody = new RigidBody(fallRigidBodyCI); 

    //now we add it to our physics simulation 
    dynamicsWorld.addRigidBody(fallRigidBody); 

    for (int i=0 ; i<300 ; i++) { 
        dynamicsWorld.stepSimulation(1/60.f, 10); 

        Transform trans = new Transform();
        fallRigidBody.getMotionState().getWorldTransform(trans); 


        System.out.println("sphere height: " + trans.origin.y);
    }

}
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3 に答える 3

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jBullet HelloWorld のコード例:

public static void HelloWorld() {

BroadphaseInterface broadphase = new DbvtBroadphase();
DefaultCollisionConfiguration collisionConfiguration = new DefaultCollisionConfiguration();
CollisionDispatcher dispatcher = new CollisionDispatcher(collisionConfiguration);

SequentialImpulseConstraintSolver solver = new SequentialImpulseConstraintSolver();

DiscreteDynamicsWorld dynamicsWorld = new DiscreteDynamicsWorld(dispatcher, broadphase, solver, collisionConfiguration);

// set the gravity of our world
dynamicsWorld.setGravity(new Vector3f(0, -10, 0));

// setup our collision shapes
CollisionShape groundShape = new StaticPlaneShape(new Vector3f(0, 1, 0), 1);
CollisionShape fallShape = new SphereShape(1);

// setup the motion state
DefaultMotionState groundMotionState = new DefaultMotionState(new Transform(new Matrix4f(new Quat4f(0, 0, 0, 1), new Vector3f(0, -1, 0), 1.0f))); 

RigidBodyConstructionInfo groundRigidBodyCI = new RigidBodyConstructionInfo(0, groundMotionState, groundShape, new Vector3f(0,0,0)); 
RigidBody groundRigidBody = new RigidBody(groundRigidBodyCI); 

dynamicsWorld.addRigidBody(groundRigidBody); // add our ground to the dynamic world.. 

// setup the motion state for the ball
DefaultMotionState fallMotionState = new DefaultMotionState(new Transform(new Matrix4f(new Quat4f(0, 0, 0, 1), new Vector3f(0, 50, 0), 1.0f)));

//This we're going to give mass so it responds to gravity 
int mass = 1;

Vector3f fallInertia = new Vector3f(0,0,0); 
fallShape.calculateLocalInertia(mass,fallInertia); 

RigidBodyConstructionInfo fallRigidBodyCI = new RigidBodyConstructionInfo(mass,fallMotionState,fallShape,fallInertia); 
RigidBody fallRigidBody = new RigidBody(fallRigidBodyCI); 

//now we add it to our physics simulation 
dynamicsWorld.addRigidBody(fallRigidBody); 

for (int i=0 ; i<300 ; i++) { 
    dynamicsWorld.stepSimulation(1/60.f, 10); 

    Transform trans = new Transform();
    fallRigidBody.getMotionState().getWorldTransform(trans); 


    System.out.println("sphere height: " + trans.origin.y);
}

}

于 2012-10-21T17:36:07.800 に答える
1

jMonkeyEngineのデモとサンプルコードを確認しましたか？

これらのかなりの数が物理エンジンとしてjBulletを使用しており、間違いなく試してみる価値があります。

于 2012-10-17T05:39:29.950 に答える
1

作業中のチュートリアルのサンプル コードを見てみましょう。コードにコメントを追加したので、何が起こっているのか、コードをどのように設定する必要があるのか​​ をよりよく理解できます。以下のコードは実際には何も表示しないことに注意してください。基本的には、物理​​オブジェクトである地面を作成し、オブジェクトを地面に落下させ、シミュレーションを進むにつれてオブジェクトの高さを出力します。

int main (void)
{
    //Set up all the required objects and controllers for simulating the physics
    //all this stuff would actually go into whatever initialize function you have
    btBroadphaseInterface* broadphase = new btDbvtBroadphase();

    btDefaultCollisionConfiguration* collisionConfiguration = new btDefaultCollisionConfiguration();
    btCollisionDispatcher* dispatcher = new btCollisionDispatcher(collisionConfiguration);

    btSequentialImpulseConstraintSolver* solver = new btSequentialImpulseConstraintSolver;

    btDiscreteDynamicsWorld* dynamicsWorld = new btDiscreteDynamicsWorld(dispatcher,broadphase,solver,collisionConfiguration);

    dynamicsWorld->setGravity(btVector3(0,-10,0));

    //Create our physics objects, the planeShape is the ground
    btCollisionShape* groundShape = new btStaticPlaneShape(btVector3(0,1,0),1);

    //A sphere that will be dropping to the ground, 
    btCollisionShape* fallShape = new btSphereShape(1);

    //Create motion states for our objects
    //First the ground object. It will be in the XZ plane at -1 Y
    //note that we're not giving it any mass
    //zero mass in a physics simulation means it won't move when collided with
    //it also means that it won't respond to gravity
    btDefaultMotionState* groundMotionState = new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(0,-1,0)));
    btRigidBody::btRigidBodyConstructionInfo
                groundRigidBodyCI(0,groundMotionState,groundShape,btVector3(0,0,0));
    btRigidBody* groundRigidBody = new btRigidBody(groundRigidBodyCI);

    //Add the ground to the simulation
    dynamicsWorld->addRigidBody(groundRigidBody);

    //now set up the motion state for our sphere, we'll put it at 50 Y
    btDefaultMotionState* fallMotionState =
                new btDefaultMotionState(btTransform(btQuaternion(0,0,0,1),btVector3(0,50,0)));
    //This we're going to give mass so it responds to gravity
    btScalar mass = 1;
    btVector3 fallInertia(0,0,0);
    fallShape->calculateLocalInertia(mass,fallInertia);
    btRigidBody::btRigidBodyConstructionInfo fallRigidBodyCI(mass,fallMotionState,fallShape,fallInertia);
    btRigidBody* fallRigidBody = new btRigidBody(fallRigidBodyCI);

    //now we add it to our physics simulation
    dynamicsWorld->addRigidBody(fallRigidBody);


    //Here's where the magic happens. The physics simulation is stepped.
    //for each step, we're going to get the balls current position and write it out.
    //Everything inside this for loop would actually go into your *update* loop
    //your update loop would step the physics simulation
    //after stepping the simulation, you get the positions of your physics bodies
    //and make sure your object positions match those.

    for (int i=0 ; i<300 ; i++) {
            dynamicsWorld->stepSimulation(1/60.f,10);

            btTransform trans;
            fallRigidBody->getMotionState()->getWorldTransform(trans);

            //so you would take `trans` and use it to set the position of your cube
            //then your cube position would be updated to the same position as 
            //this physics object that's representing it.

            std::cout << "sphere height: " << trans.getOrigin().getY() << std::endl;
    }

    //everything else is clean up

    dynamicsWorld->removeRigidBody(fallRigidBody);
    delete fallRigidBody->getMotionState();
    delete fallRigidBody;

    dynamicsWorld->removeRigidBody(groundRigidBody);
    delete groundRigidBody->getMotionState();
    delete groundRigidBody;


    delete fallShape;

    delete groundShape;


    delete dynamicsWorld;
    delete solver;
    delete collisionConfiguration;
    delete dispatcher;
    delete broadphase;

    return 0;
}

基本的に、物理シミュレーション内でゲームの世界を再現したいと考えています。次に、物理シミュレーションをステップ実行すると、ゲームの世界がシミュレーションからの新しい位置で更新されます。物理シミュレーションは、ゲーム オブジェクトを動かして、互いに衝突しているように見せる方法を教えてくれます。

したがって、セットアップでは、ループ内のものをfor更新ループに移動します。次に、球の位置をコンソールに書き出す代わりに、 , を球の位置で更新posXしposYますposZ。これで、キューブはシミュレーションの球体とまったく同じように動きます!

したがって、ポイントの最後のプッシュです。2 つの世界を作成しています。詳細なグラフィックを描いているものと、詳細なグラフィック オブジェクトの物理的な形状を表す単純な形状を持っているものです。物理世界はすべてのオブジェクトの相互作用をシミュレートしており、詳細グラフィック オブジェクトはこれらの単純な物理的形状の位置を反映しているだけです。

うまくいけば、それは物事をより明確にします。

于 2012-10-19T04:59:30.883 に答える