Returning a polymorphic class - c++

Question

i'm creating a little xbox application and for the beginning it should detect what game is currently running and then bypass and/or launch a program. Since i recently learned polymorphism i thought i could implement it here to gain efficiency. Below is my code (not as efficient as i thought it would be):
DWORD(__cdecl *XamGetCurrentTitleID)() = (DWORD(__cdecl *)())ResolveFunction("xam.xex", 0x1CF); // Resolves current Game ID
typedef enum _XBOX_GAMES : DWORD // Enum that holds Game IDs
{
BOOT_UP = 0x00000000,
DASHBOARD = 0xFFFE07D1,
FREESTYLEDASH = 0xF5D20000,
COD_WORLD_AT_WAR = 0x4156081C,
COD_MODERN_WARFARE = 0x415607E6,
COD_MODERN_WARFARE_2 = 0x41560817,
COD_BLACK_OPS_1 = 0x41560855,
COD_MODERN_WARFARE_3 = 0x415608CB,
COD_BLACK_OPS_2 = 0x415608C3,
COD_GHOSTS = 0x415608fC,
COD_ADVANCED_WARFARE = 0x41560914,
COD_BLACK_OPS_3 = 0x4156091D,
DESTINY = 0x415608F8,
GTAV = 0x545408A7
} XBOX_GAMES;
DWORD GameChecker()
{
DWORD lastID = NULL;
Game *game;
AW aw; BO1 bo1; BO2 bo2; BO3 bo3; Ghosts ghosts; MW2 mw2; MW3 mw3; Dashboard dashboard;
for (;;)
{
if (XamGetCurrentTitleID() != lastID)
{
switch (XamGetCurrentTitleID())
{
case BOOT_UP:
// nothing
break;
case DASHBOARD:
game = &dashboard;
game->Launch();
break;
case COD_MODERN_WARFARE_2:
game = &mw2;
game->Launch();
break;
case COD_MODERN_WARFARE_3:
game = &mw3;
game->Launch();
break;
case COD_GHOSTS:
game = &ghosts;
game->Bypass();
game->Launch();
break;
case COD_BLACK_OPS_1:
game = &bo1;
game->Launch();
break;
case COD_BLACK_OPS_2:
game = &bo2;
game->Bypass();
break;
case COD_BLACK_OPS_3:
game = &bo3;
game->Bypass();
break;
case COD_ADVANCED_WARFARE:
game = &aw;
game->Bypass();
game->Launch();
break;
}
lastID = XamGetCurrentTitleID();
}
}
return 0;
}
As you can see i could've moved the game->Launch() and game->Bypass() outside of the switch statement to have less code and only call it once, but i didn't knew how i could determine when a game needs a bypass and/or launch. This is my GameClass:
class Game
{
public:
virtual void Bypass() { }
virtual void Launch() { }
};
And this is the class of an example game:
// needs bypass and launch called
class AW : public Game
{
public:
void Bypass()
{
// bypass
}
void Launch()
{
Sleep(500);
XNotifyUI(L"AW - Loaded!");
}
};
I would like to know if there is a way to do something like this:
DWORD GameChecker()
{
DWORD lastID = NULL;
Game *game;
for (;;)
{
if (XamGetCurrentTitleID() != lastID)
{
switch (XamGetCurrentTitleID())
{
case BOOT_UP:
// nothing
break;
default:
game = &functionThatReturnsClassBasedOnGame(XamGetCurrentTitleID()); // I don't know how to code such an function
break;
}
if (game->needsBypass)
game->Bypass();
if (game->needsLaunch)
game->Launch();
lastID = XamGetCurrentTitleID();
}
}
return 0;
}
Any help is greatly appreciated! Thanks for your time.

Answer 1

A simple way to accomplish your example is like this:
const int NEEDS_BYPASS = 1;
const int NEEDS_LAUNCH = 2;
class Game
{
public:
virtual ~Game() { }
virtual int getFeatures() const { return 0; }
virtual void Bypass() { }
virtual void Launch() { }
};
class Game_Dashboard : public Game
{
public:
int getFeatures() const { return NEEDS_LAUNCH; }
void Launch() {
Sleep(500);
XNotifyUI(L"Dashboard - Loaded!");
}
};
class Game_ModernWarfare2 : public Game
{
public:
int getFeatures() const { return NEEDS_LAUNCH; }
void Launch() {
Sleep(500);
XNotifyUI(L"MW2 - Loaded!");
}
};
class Game_ModernWarfare3 : public Game
{
public:
int getFeatures() const { return NEEDS_LAUNCH; }
void Launch() {
Sleep(500);
XNotifyUI(L"MW3 - Loaded!");
}
};
class Game_Ghosts : public Game
{
public:
int getFeatures() const { return NEEDS_BYPASS | NEEDS_LAUNCH; }
void Bypass() {
// bypass...
}
void Launch() {
Sleep(500);
XNotifyUI(L"Ghosts - Loaded!");
}
};
class Game_BlackOpts1 : public Game
{
public:
int getFeatures() const { return NEEDS_LAUNCH; }
void Launch() {
Sleep(500);
XNotifyUI(L"BO1 - Loaded!");
}
};
class Game_BlackOpts2 : public Game
{
public:
int getFeatures() const { return NEEDS_BYPASS; }
void Bypass() {
// bypass...
}
};
class Game_BlackOpts3 : public Game
{
public:
int getFeatures() const { return NEEDS_BYPASS; }
void Bypass() {
// bypass...
}
};
class Game_AdvancedWarfare : public Game
{
public:
int getFeatures() const { return NEEDS_BYPASS | NEEDS_LAUNCH; }
void Bypass() {
// bypass
}
void Launch() {
Sleep(500);
XNotifyUI(L"AW - Loaded!");
}
};
Game* getGame(DWORD ID)
{
switch (ID)
{
case DASHBOARD:
return new Game_Dashboard;
case COD_MODERN_WARFARE_2:
return new Game_ModernWarfare2;
case COD_MODERN_WARFARE_3:
return new Game_ModernWarfare3;
case COD_GHOSTS:
return new Game_Ghosts;
case COD_BLACK_OPS_1:
return new Game_BlackOpts1;
case COD_BLACK_OPS_2:
return new Game_BlackOpts2;
case COD_BLACK_OPS_3:
return new Game_BlackOpts3;
case COD_ADVANCED_WARFARE:
return new Game_AdvancedWarfare;
}
return NULL;
}
DWORD GameChecker()
{
DWORD currentID, lastID = 0;
Game *game;
do
{
currentID = XamGetCurrentTitleID();
if (currentID != lastID)
{
lastID = currentID;
game = getGame(currentID);
if (game)
{
if (game->getFeatures() & NEEDS_BYPASS)
game->Bypass();
if (game->getFeatures() & NEEDS_LAUNCH)
game->Launch();
delete game;
}
}
}
while (true);
return 0;
}
However, a better use of polymorphism would to be more like this instead:
class Game
{
public:
virtual ~Game() { }
};
class CanBypass
{
public:
virtual void Bypass() = 0;
};
class CanLaunch
{
public:
virtual void Launch() = 0;
};
class Game_Dashboard : public Game, public CanLaunch
{
public:
void Launch() {
Sleep(500);
XNotifyUI(L"Dashboard - Loaded!");
}
};
class Game_ModernWarfare2 : public Game, public CanLaunch
{
public:
void Launch() {
Sleep(500);
XNotifyUI(L"MW2 - Loaded!");
}
};
class Game_ModernWarfare3 : public Game, public CanLaunch
{
public:
void Launch() {
Sleep(500);
XNotifyUI(L"MW3 - Loaded!");
}
};
class Game_Ghosts : public Game, public CanBypass, public CanLaunch
{
public:
void Bypass() {
// bypass...
}
void Launch() {
Sleep(500);
XNotifyUI(L"Ghosts - Loaded!");
}
};
class Game_BlackOpts1 : public Game, public CanLaunch
{
public:
void Launch() {
Sleep(500);
XNotifyUI(L"BO1 - Loaded!");
}
};
class Game_BlackOpts2 : public Game, public CanBypass
{
public:
void Bypass() {
// bypass...
}
};
class Game_BlackOpts3 : public Game, public CanBypass
{
public:
void Bypass() {
// bypass...
}
};
class Game_AdvancedWarfare : public Game, public CanBypass, public CanLaunch
{
public:
void Bypass() {
// bypass
}
void Launch() {
Sleep(500);
XNotifyUI(L"AW - Loaded!");
}
};
Game* getGame(DWORD ID)
{
switch (ID)
{
case DASHBOARD:
return new Game_Dashboard;
case COD_MODERN_WARFARE_2:
return new Game_ModernWarfare2;
case COD_MODERN_WARFARE_3:
return new Game_ModernWarfare3;
case COD_GHOSTS:
return new Game_Ghosts;
case COD_BLACK_OPS_1:
return new Game_BlackOpts1;
case COD_BLACK_OPS_2:
return new Game_BlackOpts2;
case COD_BLACK_OPS_3:
return new Game_BlackOpts3;
case COD_ADVANCED_WARFARE:
return new Game_AdvancedWarfare;
}
return NULL;
}
DWORD GameChecker()
{
DWORD currentID, lastID = 0;
Game *game;
CanBypass *bypasser;
CanLaunch *launcher;
do
{
currentID = XamGetCurrentTitleID();
if (currentID != lastID)
{
lastID = currentID;
game = getGame(currentID);
if (game)
{
bypasser = dynamic_cast<CanBypass*>(game);
if (bypasser)
bypasser->Bypass();
launcher = dynamic_cast<CanLaunch*>(game);
if (launcher)
launcher->Launch();
delete game;
}
}
}
while (true);
return 0;
}