# Creating a simple game using Havok Physics

Hi everybody, Here is an article describing how to build a simple 3D physics-based game using Havok 2011.3. The article has also been published on Game Coder Magazine Physics some weeks ago. Enjoy!

# New Havok Instructional Videos

Greetings everyone,

I've recently come across some rather helpful videos regarding Havok Physics which I wanted to pass along to the community. These are great instructional videos for beginners/advanced users alike and are based on the free SDK you all have. Please take a look!

Havok Instructional Videos

Cheers,
Jason G.

How to report a crash

I'm not trying to single out anybody here; I'm just trying to save everybody some frustration. Let's consider the following two hypothetical forum posts:

1) "After I call hkpWorld::initMtStep, I get a message that says "hkpWorld.cpp(123): [0x12345678] Warning : I'm about to crash". Right after that I get a assert with the message "hkpWorld.cpp(234): [0x00001337] Assert : foo != HK_NULL" and this callstack:

# Welcome Havok Users

Hi:

I'd like to welcome everyone to our community support site for the Havok Physics and Havok Animation downloads for the PC, which can be found at www.havok.com/try-havok

To get started you may find these intructional videos useful: Havok Instructional Videos

# Dynamic rigid body with complex compound shape

Hi!

I'm using rigid bodies with complex compound shape (hundreds of box shapes alligned to uniform grid).

What best compound shape for this case?
I've tried hkpBvCompressedMeshShape, but it's quite slow in narrow phase (~20ms)

hkpMoppBvTreeShape is faster in narrow phase (~5-10ms), but when object is moving in empty space (no other objects at all), it's quite slow (~5-10ms). Why is Mopp slow when it's just moving?

# Problem with Havok math classes.

If I try to use any of the Havok math classes (hkMatrix4, hkTransform) as members of a class my software crashes when trying to use them. Ex.

class TestClass
{
public:
hkMatrix4    _t1;

void test();

};
void TestClass::test()
{
_t1.setIdentity();
}

void TestClass::test2()
{

hkMatrix4    t2;
t2.setIdentity();
}

The above code will crash on test1 but not test2. Any one know whats going on here?

Cheers,

Keith

# hkpRigidBody without shape and custom inertia.

I'm doing some testing of the Havok Physics sdk to see if it meets the requirements of my engine. Does anyone know if a hkpRigidBody can be created with out any shapes added? I'm trying to create a dynamic object with out any collision and a custom inerta matrix but I'm getting a crash when I try to create a new  hkpRigidBody with bodyCinfo.m_shape set to NULL.

# Most likely causes for linearCastPhantomCast and collision queries achieving poor performance

I am in need of a more experienced user's input on a particular issue of having to optimize an engine that's used for multiple platforms.

# Character Friction

Is there any way to set the rate at which a hkpCharacterRigidBody will come to rest?

# [video]Ragdoll and hkaRagdollPoweredConstraintController issues

Hello everyone,

Sorry for creating the same topic twice, but I was unable to create a topic with yt link, nor I couldn't upload mp4 file as attachment - the topic just wasn't being created despite the 'success' message. Not to mention that I can't edit my previous posts, I don't know, maybe its a new user restriction or a board policy in general...