L
Ich habe die Idee mal in einem anderen Forum diskutiert, siehe
http://www.gamedev.net/community/forums/topic.asp?topic_id=424879
Basierend auf einem Vorschlag von einem Member dort komme ich auf die folgende, noch elegantere Version.
DelegatorBase<Missile> DelegatorBase<LaserGun>
\ /
\ /
XWing SpaceshipBase BWing
| \ ______________/ / \ \_________________ / |
| \ / / \ \ / |
| \_________/______ / \ ___\___/ |
| / \ / \ / \ |
| / \ / \ / \ |
DelegatorT<XWing, Missile> \ / DelegatorT<BWing, Missile> \ |
\ \ / | \ |
\ DelegatorT<XWing, LaserGun> | DelegatorT<BWing, LaserGun>
\ / | /
\ / | /
SpaceshipT<XWing> SpaceshipT<BWing>
// general framework
//---------------------------------------------------------------------------
template<struct Weapon> struct DelegatorBase {
virtual void hit_v(Weapon*)=0;
};
struct SpaceshipBase :
DelegatorBase<Weapon_1>, // can be achieved in code size O(1)
...,
DelegatorBase<Weapon_k>
{
template<struct Weapon> hit() {hit_v((Weapon*)0);}
};
template<struct ShipType, struct Weapon> struct DelegatorT :
virtual ShipType,
virtual SpaceshipBase
{
virtual void hit_v(Weapon*) {hit_impl<Weapon>();}
};
template<struct ShipType> struct SpaceshipT :
DelegatorT<ShipType, Weapon_1>, // can be achieved in code size O(1)
...,
DelegatorT<ShipType, Weapon_k>
{
};
// specific spaceships
//---------------------------------------------------------------------------
struct Type_XWing {
template<struct Weapon> void hit_impl() {...}
};
struct Type_StarDestroyer {
template<struct Weapon> void hit_impl() {...}
};
// specific weapons
//---------------------------------------------------------------------------
struct Missile {...};
template<int n> struct RailgunT // Railgun type n
{...};
// usage
//---------------------------------------------------------------------------
void main() {
SpaceshipBase* spaceship = new SpaceshipT<Type_XWing>();
spaceship->hit<Missile>();
}
Vorteil: Beim Implementieren der Schiffstypen muss man sich nicht mehr mit der komplizierten Architektur herumschlagen.
