Question

这里我在box2d做一个小游戏。因为我想要一个像Lift一样自动上下移动的身体。我尝试使用此代码的代码可以在我触摸时移动。但我希望移动y位置0到480并再次将480反转为0.

enter code here

//Set up a 1m squared box in the physics world
    b2BodyDef bodyDef;
    bodyDef.type = b2_dynamicBody;

    bodyDef.position.Set(p.x/PTM_RATIO, p.y/PTM_RATIO);
    bodyDef.userData = sprite;
    b2Body *body = world->CreateBody(&bodyDef);

    // Define another box shape for our dynamic body.
    b2PolygonShape dynamicBox;
    dynamicBox.SetAsBox(.5f, .5f);//These are mid points for our 1m box

    // Define the dynamic body fixture.
    b2FixtureDef fixtureDef;
    fixtureDef.shape = &dynamicBox; 
    fixtureDef.density = 1.0f;
    fixtureDef.friction = 0.3f;
    body->CreateFixture(&fixtureDef);
- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    //Add a new body/atlas sprite at the touched location
    for( UITouch *touch in touches ) {
        CGPoint location = [touch locationInView: [touch view]];

        location = [[CCDirector sharedDirector] convertToGL: location];

        //[self addNewSpriteWithCoords: location];
        b2Vec2 force = b2Vec2(0, 20);
        _body->ApplyLinearImpulse(force, _body->GetPosition());
    }
}

Answer 1

请参阅此处的关节部分：

http://www.box2d.org/manual.html

棱柱关节可能对此有好处。如果它应该是电梯/电梯，你可能还想考虑一个运动机构，但实际上这取决于你希望实现的目标。绝对检查一下body部分中运动学和动态（和静态）主体之间的区别。

如何创建像Lift一样移动box2d的身体（身体可以自动向上和向下移动）

1 个答案: