Callbacks in LEO

[Laurens]

Hi,

 

Could someone please give me an example of how to create a callback using LEO? I currently have the following (non-functional) code:

 

ball.cpp

 

ball.SetCallback((byte*)paddle->EntityCollisionCallback, ENTITYCALLBACK_COLLISION);

 

paddle.h

 

void EntityCollisionCallback(TEntity source, TEntity destination, byte* position, byte* normal, byte* force, float speed);

 

Thanks!

[Rick]

Is paddle->EntityCollisionCallbackdefined as static?

[Laurens]

Is paddle->EntityCollisionCallbackdefined as static?

 

No, it's an instance. I had hoped I could pull that off using LEO but since you're asking I guess I should implement the callback "plain old" C-style?

[Rick]

Since LEO is just a wrapper for LE, at it's core it's still uses LE's function to setup callbacks. It sucks, I know.

 

I have a way to map these to class members but it's probably just as easy to use the C style. Even the mapping way is done with the normal C callback, but inside that callback you map it back to the class function to call. Would have been cooler if LEO did that automatically.

[Laurens]

Well my code compiles now. A new issue has risen though. My code now looks like this:

 

ball.cpp

 

ball.SetCallback((byte*)Paddle::EntityCollisionCallback, ENTITYCALLBACK_COLLISION);

 

paddle.cpp

 

void _stdcall Paddle::EntityCollisionCallback(TEntity source, TEntity destination, byte* position, byte* normal, byte* force, float speed)
{
int type = GetEntityType(source);
}

 

The method is declared static in the header of the Paddle class.

 

When I run it, it detects a collision, calls the callback method between 8 to 16 times (approximately) (10 runs) without updating or rendering in between, and then craps out on framework.Update(), giving me an AccessViolationException.

 

Any idea what's going on here?

[Rick]

So if you remove the part that assigns this as a callback the framework Update() method doesn't give an error?

 

The paddle or ball doesn't get destroyed at any point in this?

[Laurens]

If I comment out the

 

ball.SetCallback((byte*)Paddle::EntityCollisionCallback, ENTITYCALLBACK_COLLISION);

 

part, than everything runs perfectly fine. The paddle nor the ball gets destroyed at any point. If I set a breakpoint in the callback function, all variables also get properly set. No bad pointers whatsoever.

[Rick]

Try replacing the function with just a normal C function once and see if that helps. Just for testing.

[Laurens]

Replacing the LEO function with the normal C function does not change it. I even replaced all LEO structures with the standard C structures and yet the problem persists

 

EDIT: Replacing framework.Update() with UpdateWorld() fixes the issue. I suppose this does lead to other problems since I am using Framework to render.

 

Putting it on the tracker.