Quote:Original post by Tokiko

Quote:Are you SURE you want that last line to read like that, and not like this??

    (*_collisionMap)[ second ]->addCollision( new Collision( second ) ); 

Sorry there was a typo with the first collision and it should be passing second. So if I didn't type that wrong, you would be correct :P

void CollisionSet::addCollision( GameComponent* component ){    if ( _collisionMap->find( component ) == _collisionMap->end() )         (*_collisionMap)[component] = new CollisionQueue();    (*_collisionMap)[component]->addCollision( new Collision( component ) );}// And you would just call it twice, once for each component... // since they don't depend on one another in the original functionaddCollision( first );addCollision( second );

Quote:

(*_collisionMap)[first] = new CollisionQueue();

Now with this line here. I was going to use that earlier, but I figured that it wouldn't work since you are trying to find the value paired with first, but if that key hasn't been added, how can you make a new collision? So I guess it will insert a new element if it is not found?

Quote:Original post by Tokiko

Quote:Original post by Verg
And I'm with Zahlman... is there a compelling reason to dynamically create a map? You could just use the map as an instance variable, and then you don't have to destroy it later.

This has been brought up a couple times, but I'm still not sure how I can fix this. I thought if you have a map declared in the class as a member, there are no problems with initializing it in the constructor. Can you or someone give me an example of what you would do in this case?

class YourClass {    std::map<GameComponent*, CollisionQueue*> _collisionMap;    [...]};

Quote:Original post by agi_shi

Quote:Original post by Tokiko

Quote:Original post by Verg
And I'm with Zahlman... is there a compelling reason to dynamically create a map? You could just use the map as an instance variable, and then you don't have to destroy it later.

This has been brought up a couple times, but I'm still not sure how I can fix this. I thought if you have a map declared in the class as a member, there are no problems with initializing it in the constructor. Can you or someone give me an example of what you would do in this case?

I believe they meant like so:

class YourClass {    std::map<GameComponent*, CollisionQueue*> _collisionMap;    [...]};

The _collisionMap will be allocated on the stack, not the free-store (heap). Thus, no messy allocation/destruction (new/delete).

Original post by Tokiko

Quote:

Quote:

void CollisionSet::addCollision( GameComponent* component ){    if ( _collisionMap->find( component ) == _collisionMap->end() )         (*_collisionMap)[component] = new CollisionQueue();    (*_collisionMap)[component]->addCollision( new Collision( component ) );}// And you would just call it twice, once for each component... // since they don't depend on one another in the original functionaddCollision( first );addCollision( second );

I wouldn't be able to simplify it to that. When I make the collision object for the first component, I need to pass the second component so that I know what collided with it. Same goes for the second component - I pass the first one to the collision object. With your code, you would be creating a collision between the component and itself.

That code was just a simplification of what you'd already written.

In your previous code there was no interaction between the two objects... they were just parameters in the same function.

If there needed to be interaction, your original code was not doing that.

Quote:

void CollisionSet::addCollision( GameComponent* component ){    if ( _collisionMap->find( component ) == _collisionMap->end() )         (*_collisionMap)[component] = new CollisionQueue();    (*_collisionMap)[component]->addCollision( new Collision( component ) );}// And you would just call it twice, once for each component... // since they don't depend on one another in the original functionaddCollision( first );addCollision( second );

void CollisionSet::addCollision( GameComponent* first, GameComponent *second ){    if ( _collisionMap->find( first ) == _collisionMap->end() )         (*_collisionMap)[first] = new CollisionQueue();    (*_collisionMap)[first]->addCollision( new Collision( second ) );}addCollision( first , second );addCollision( second , first );

Quote:Original post by rip-off

Quote:Original post by agi_shi

Quote:Original post by Tokiko

Quote:Original post by Verg
And I'm with Zahlman... is there a compelling reason to dynamically create a map? You could just use the map as an instance variable, and then you don't have to destroy it later.

This has been brought up a couple times, but I'm still not sure how I can fix this. I thought if you have a map declared in the class as a member, there are no problems with initializing it in the constructor. Can you or someone give me an example of what you would do in this case?

I believe they meant like so:

class YourClass {    std::map<GameComponent*, CollisionQueue*> _collisionMap;    [...]};

The _collisionMap will be allocated on the stack, not the free-store (heap). Thus, no messy allocation/destruction (new/delete).

Almost [smile]. The _collisionMap will be allocated wherever the "YourClass" instances are allocated. This could either be on the stack or the heap.

However it will be automatically initialised and destroyed (implicitly in the constructor/destructor). Its lifetime is the same as the object that owns it.