Using BOX2D just for collision makes sprites get moved very fast

@abrajam wrote:

Hi, I putted a physics body to all my sprites that I want to check for collision, but I really not want to use the other physics features like gravity, friction, etc just need a more precise collision than just checking for intersection between bounding boxes.

The thing is that when I set physicsworld and physicbodies my characters get moving very fast compared to the movement made without setting a physics world. I move them on the game with setPositionY(getPositionY + speed * dt) I mean no physic forces, is there a way to prevent what is happening? Please give me some help because I think that they are kinematic bodies and shouldn’t be affected this way by the physics but somehow they do and I can’t find the setting to prevent it, also the documentation is out of my understanding and it differs between classical BOX2D and the implementation of cocos2d-x of this library.

On my scene I set this:

#if _USE_PHYSICS == 1

if (!Scene::initWithPhysics())
        return false;

//getPhysicsWorld()->setDebugDrawMask(PhysicsWorld::DEBUGDRAW_ALL);
getPhysicsWorld()->setGravity(Vec2(0.0f, 0.0f));
getPhysicsWorld()->setSpeed(0.0f);

MyBodyParser::getInstance()->parseJsonFile("Physics");

#elif _USE_PHYSICS == 0

if (!Scene::init())
    return false;

#endif

and in my characters like this, I vary the 3 parameters for Physics Material but I see no difference:

if (!Sprite::initWithSpriteFrameName(_ENEMY_IDLE_PATH))
    return false;

#if _USE_PHYSICS == 1
    auto phBody = MyBodyParser::getInstance()->bodyFormJson(this, "Enemy", PhysicsMaterial(1.0f, 0.0f, 10.0f));
    phBody->setDynamic(false);
    phBody->setGravityEnable(false);
    this->setPhysicsBody(phBody);
#endif

and like this:

if (!Sprite::initWithSpriteFrame(SpriteFrameCache::getInstance()->getSpriteFrameByName(filename)))
    return false;

setVisible(false);

#if _USE_PHYSICS == 1

auto phBody = MyBodyParser::getInstance()->bodyFormJson(this,
                                                        (_type == UP_BULLET) ? "BulletPlayer" : "BulletEnemy",
                                                        PhysicsMaterial(10.0f, 0.0f, 10.0f));

phBody->setDynamic(false);
phBody->setGravityEnable(false);
this->setPhysicsBody(phBody);

#endif

Hope somebody could help, thanks.

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