When I create a handle of an object,
remove the object (ent_remove)
and retreive it (ENITY) later with
ptr_for_handle,
the engine will call an error on warn_level > 1

But checking if the handle is NULL before retreiving the pointer does not work.

How do I know if a handle is empty, or an invalid (removed) object
BEFORE calling ptr_for_handle?

Example:

any idea how to check a handle, if its valid?

As far as i remember you are doing it the right way. entites[i] is a var array and the entites are saved with handle(ENTITY*) there, right?

when warn_level is set > 1, a warning is issued, but you can ignore it. only solution is to set warn_level to 1.

But why is there no way to check if a handle is null,
before having the engine issue a warning.

There must a a "right" way to handle this.
Or did the engine creators forget about this
(rather standard) case?
some command like ptr_is_valid(handleid);


by lowering the warn_level I would miss other errors,
that could come up.

entities[entityToKill.id] = 0;
ent_remove(entityToKill);

Is that an acceptable workaround for you?

No, after the entity is removed, its pointer is null/invalid (and thus all skills are unreadalbe),
and I operate on a list of handles to entities, read out
by other codeparts.

I guess its simply an engine flaw, to miss
a robust way to check for valid handles, without a
warning thrown.

When I develop something, I always like to have errors thrown and not swallowed,
but not if there is no correct way to handle it.



But thanks for your help

I don't understand. When you remove the entity, simply set the corresponding handle to zero, i.e. before the ptr_/ent_remove instruction.
Then, in your list of handles, the handle will be zero and thus can be ignored, so you don't have to call ptr_for_handle anymore.

I know what you mean.
But there is not only a single array for each handle.

There are many possible locations, and references where it
could have been stored before.
And I cant resolve all of them.
So this would be only a workaround for this specific case.

Ok, then you could/ should contact the developers so ptr_for_handle returns NULL when the handle is invalid.

Right now I have the problem that a removed entity
is not recognized as NULL, but
is like a "ZERO" entity, with positiondata at 0,0,0 for example.

This engine really has some flaws.


if(myTarget!=NULL)
{
if((myTarget.x==0) && (myTarget.z==0) ) {ent_remove(myTarget);}

-> results in a crash, because myTarget is NULL ...

so first its Not Null, then its Null...
Very good engine programming