How to detect entity [properties] ?

**How to detect entity [properties] ? -** 26-05-2004

Code:

 if (strcmp("dod_control_point", item_name) == 0)

I can use this code to detect a control point, however, I need more information of this control point, I knew the dod_control_point have more properties like :

point_allies_model
point_allies_model_bodygroup
point_allies_target
point_allies_win_string
etc......

But how can I detect it ?

Pierre-Marie Baty · **Re: How to detect entity [properties] ? -** 26-05-2004

I don't know... are you talking about the entity's infobuffer ?

Look in some CS bot source code for the function that tells which team a bot is on. It calls the infobuffer and retrieves the "model" field. You may use the same method I believe. (curious, though, as I believed only game clients could have infobuffers ?)

botman · **Re: How to detect entity [properties] ? -** 26-05-2004

PM, I think he's refering to properties (key/value pairs) that can be set by level designers (mappers).

Tea, entity variables are usually stored as Class member variables in the MOD source code class definition (which you don't have the source code for). You can access these values by using the pvPrivateData point in the entvars structure. The pvPrivateData will point to the memory allocated by the engine for that Class instance. For example, if you create a CBasePlayer class in the MOD code, the engine will allocate space for the CBasePlayer class (which will probably not contain the same variables that the standard Half-Life SDK source code comes with, so don't assume these are the same). You can dump the pvPrivateData section of memory to see what byte values change when one of these class member variables is updated.

A cleaner way to do this is to intercept the entity being spawned by the engine. The HPB bot does this for several entities, for example in TFC, the "info_tfdetect" entity is used to determine how many players are allowed on each team and how many teams there are. I intercept the "info_tfdetect" entity when it is being spawned and save the values of the key/value pairs in DispatchKeyValue() (in the dll.cpp file) when the entity is spawned. This method will ONLY work for things that DON'T change their value while the game is being played. For example, if you had something that toggle off and on (like a capture point) while the game is playing, you would have to intercept other network messages to know what the current state of that entity is.

botman

BAStumm · **Re: How to detect entity [properties] ? -** 26-05-2004

Code:

		//DoD flag info
		for (i = 0; i < DOD_FLAG_MAX && (pent = UTIL_FindEntityByClassname(pent, "dod_control_point")) != NULL; i++)
		{
				flag_team = -1;
		 
				sprintf(temp_data[DOD_FLAG_NUM][i + 1], "%i", i);
				sprintf(temp_data[DOD_FLAG_X_COORD][i + 1], "%f", pent->v.origin.x - x_offset);
				sprintf(temp_data[DOD_FLAG_Y_COORD][i + 1], "%f", pent->v.origin.y - y_offset);
				sprintf(temp_data[DOD_FLAG_Z_COORD][i + 1], "%f", pent->v.origin.z);
				sprintf(temp_data[DOD_FLAG_TEAM][i + 1], "%i", pent->v.body);
				sprintf(temp_data[DOD_FLAG_MODEL][i + 1], "%s", STRING(pent->v.model));
				sprintf(temp_data[DOD_FLAG_NAME][i + 1], "%s", STRING(pent->v.netname));
		}

*Last edited by Tea; 27-05-2004 at 00:19..*

Code:

 
 
void KeyValue( edict_t *pentKeyvalue, KeyValueData *pkvd )
{
int dod_flag = 0;
 
if (mod_id == DOD_DLL)
{
	if (pentKeyvalue == pent_dod_control_point)
	{
		if (strcmp(pkvd->szKeyName, "point_allies_target") == 0)
			dod_flag = atoi(pkvd->szValue);
	}
} 
 
RETURN_META (MRES_IGNORED);
}

Botman tks for the reply, I have added this code in dll.cpp, is it correct ? And if I want to call this function in bot.cpp, what command should I use ? something like keyvalue ( ??? ); ?

BAStumm, since I am very new of bot coding and C++ so I didn't understand the code you show me, could you tell me more detail what are each line of the code doing so I can learn it but not just copy it, thank you very much.

botman · *Last edited by botman; 27-05-2004 at 16:29..*

Intercepting the key/value pairs of an entity is a little more complex than that. First you have to store the entvars pointer when the entity is created, then in DispatchKeyValue, when keys are stored for that specific entity, you can examine what the values of those keys are.

For the HPB bot, I keep a global variable to store the pent (entvars pointer)...

Code:

edict_t *pent_info_tfdetect = NULL;

This variable gets NULLed out everytime a new map begins loading (when the code sees the "worldspawn" entity being created).

In DispatchKeyValue(), I check to see if an entity is being created by looking for the "classname" key (since Worldcraft/Hammer always makes the "classname" for entities the first key to be passed into the MOD code)...

Code:

	 else if (pent_info_tfdetect == NULL)
	 {
		 if ((strcmp(pkvd->szKeyName, "classname") == 0) &&
			 (strcmp(pkvd->szValue, "info_tfdetect") == 0))
		 {
			pent_info_tfdetect = pentKeyvalue;
		 }
	 }

....and then, also in DispatchKeyValue(), when other keys are being passed to the MOD code, I compare the pentKeyvalue being passed in to the pointer of the specific entity I am looking for and check which key is being passed in...

Code:

 if (mod_id == TFC_DLL)
{
	 if (pentKeyvalue == pent_info_tfdetect)
	 {
		 if (strcmp(pkvd->szKeyName, "ammo_medikit") == 0) // max BLUE players
			max_team_players[0] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "ammo_detpack") == 0) // max RED players
			max_team_players[1] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "maxammo_medikit") == 0) // max YELLOW players
			max_team_players[2] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "maxammo_detpack") == 0) // max GREEN players
			max_team_players[3] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "maxammo_shells") == 0) // BLUE class limits
			team_class_limits[0] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "maxammo_nails") == 0) // RED class limits
			team_class_limits[1] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "maxammo_rockets") == 0) // YELLOW class limits
			team_class_limits[2] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "maxammo_cells") == 0) // GREEN class limits
			team_class_limits[3] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "team1_allies") == 0) // BLUE allies
			team_allies[0] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "team2_allies") == 0) // RED allies
			team_allies[1] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "team3_allies") == 0) // YELLOW allies
			team_allies[2] = atoi(pkvd->szValue);
		 else if (strcmp(pkvd->szKeyName, "team4_allies") == 0) // GREEN allies
			team_allies[3] = atoi(pkvd->szValue);
	 }

So in your case, you would need a global variable for the control_flag entity (assuming that was what DoD called that entity)...

Code:

edict_t *control_point = NULL;
int dod_flag; // entity 'control_flag' key "point_allies_target" calue gets stored here

...you would need to NULL it out when the world is spawned (in DispatchSpawn)...

Code:

	 if (strcmp(pClassname, "worldspawn") == 0)
	 {
		 // do level initialization stuff here...
 
		 control_point = NULL;

...and you need to add the checks in DispatchKeyValue()...

Code:

 if (mod_id == DOD_DLL)
{
	 if (pentKeyvalue == control_point)
	 {
		 if (strcmp(pkvd->szKeyName, "point_allies_target") == 0)
			dod_flag = atoi(pkvd->szValue);
	 }
	 else if (control_point == NULL)
	 {
		 if ((strcmp(pkvd->szKeyName, "classname") == 0) &&
			 (strcmp(pkvd->szValue, "control_point") == 0))
		 {
			control_point = pentKeyvalue;
		 }
	 }

...and then once the map is completely loaded, you can just examine the 'dod_flag' variable to see what the 'control_point' entity had in the "point_allies_target" key when that entity was spawned.

If there was more than one 'control_point' entity, then you would have to create and array of global edict_t pointers, and store each one separately. All of the entities that I intercept in the HPB bot code are assumed to have only 1 of those entities in each map (the HPB bot code doesn't contain any examples of reading the key/value properties from a bunch of entities having the exact same classname).

botman

*Last edited by Tea; 28-05-2004 at 04:25..*

I have tired your suggest but still no luck, then I think maybe the point_allies_target not use in this way, so I have changed to use flag_model to detect, but the result is the same........

Code:

edict_t *dod_control_point = NULL;
int dod_flag;

Code:

int Spawn( edict_t *pent )
{ 
dod_control_point = NULL;

Code:

 
void KeyValue( edict_t *pentKeyvalue, KeyValueData *pkvd )
{ 
if (mod_id == DOD_DLL)
{
if (pentKeyvalue == dod_control_point)
{
if ((strcmp(pkvd->szKeyName, "mdl") == 0) &&
	(strcmp(pkvd->szValue, "models/w_aflag.mdl") == 0))
{
	//allies flag
	dod_flag = 1;
}
else if ((strcmp(pkvd->szKeyName, "mdl") == 0) &&
	(strcmp(pkvd->szValue, "models/w_gflag.mdl") == 0))
{
	//axis flag
	dod_flag = 2;
}
else if ((strcmp(pkvd->szKeyName, "mdl") == 0) &&
	(strcmp(pkvd->szValue, "models/w_wflag.mdl") == 0))
{
	//free flag
	dod_flag = 0;
}
}
else if (dod_control_point == NULL)
{
if ((strcmp(pkvd->szKeyName, "classname") == 0) &&
	(strcmp(pkvd->szValue, "dod_control_point") == 0))
{
	dod_control_point = pentKeyvalue;
}
} 
}
RETURN_META (MRES_IGNORED);
}

And I have added some code in bot.cpp under BotFindItem()

Code:

 
void BotFindItem( bot_t *pBot )
extern int dod_flag;
{ 
if ((strcmp("dod_control_point", item_name) == 0) && (dod_flag = 0))
{
			 // check if the item is not visible (i.e. has not respawned)
			 if (pent->v.effects & EF_NODRAW)
				 continue;
 
			 FakeClientCommand(pEdict,"say","This is a FREE FLAG",0);
			 can_pickup = TRUE;
}
else if ((strcmp("dod_control_point", item_name) == 0) && (dod_flag = 1))
{
			 // check if the item is not visible (i.e. has not respawned)
			 if (pent->v.effects & EF_NODRAW)
				 continue;
 
			 FakeClientCommand(pEdict,"say","This is a ALLIES FLAG",0);
			 can_pickup = TRUE;
}
else if ((strcmp("dod_control_point", item_name) == 0) && (dod_flag = 2))
{
			 // check if the item is not visible (i.e. has not respawned)
			 if (pent->v.effects & EF_NODRAW)
				 continue;
 
			 FakeClientCommand(pEdict,"say","This is a AXIS FLAG",0);
			 can_pickup = TRUE;
}
}

Now I have few questions:

1: Bots are only keep saying This is a ALLIES FLAG no matter which flag he saw, even before he spawn(in the dead mode), he has already keep saying this, that mean dod_flag always = 1, botman could you take a quick look of my above code to see if I have any mistake ?

2: Even I force the dod_flag to 0 (dod_flag = 0) at the top of BotFindItem(), bot still keep say this is a ALLIES FLAG but not FREE flag. ???

3: How do I know if my Keyvalue() have already ran and work ?
FakeClientCommand(pEdict,"say","XXXX",0); not work in Keyvalue() , I have tried ClientPrint( pPlayer, HUD_PRINTNOTIFY, "XXXX\n"); but didn't see any message(maybe Keyvalue run before client connect ?), could you teach me which command can I use to debug in keyvalue ?

4: How can I call the Keyvalue() anytime just like the way I call the UTIL_GetTeam(pEdict) ? Please tell me the full command since I donno enter what after Keyvalue ?

Code:

Keyvalue (What should I enter here ?);

5: Which command should I use to show the pkvd->szValue to me ? Let say:

Code:

 
if (strcmp(pkvd->szKeyName, "point_allies_target") == 0)
 
{
Which command should I use to show this pkvd->szValue to me on screen ?
}

Thank you very much again for your time.

Pierre-Marie Baty · **Re: How to detect entity [properties] ? -** 28-05-2004

I don't understand why all this stuff is needed.

Wouldn't it be more simple to have something like this :

Code:

#define FLAG_ALLIES 2
#define FLAG_AXIS 1
#define FLAG_FREE 0

Code:

int GetFlagType (edict_t *pFlagEdict)
{
   // look inside pFlagEdict's entvars and stop by the model...
   if (strcmp ("models/w_aflag.mdl", STRING (pFlagEdict->v.model)) == 0)
	  return (FLAG_ALLIES); // this one is an allied flag
   else if (strcmp ("models/w_gflag.mdl", STRING (pFlagEdict->v.model)) == 0)
	  return (FLAG_AXIS); // this one is an evil nazi flag
   else
	  return (FLAG_FREE); // if none of the above, the flag must be free
}

and then later on use it like this

Code:

// in BotFindItem()
int flag_team = GetFlagType (pent);
 
if ((strcmp("dod_control_point", item_name) == 0) && (flag_team == FLAG_ALLIES))
   // do stuff for allies flag
else if ((strcmp("dod_control_point", item_name) == 0) && (flag_team == FLAG_AXIS))
   // do stuff for axis flag
else if ((strcmp("dod_control_point", item_name) == 0) && (flag_team == FLAG_FREE))
   // do stuff for free flag

**Re: How to detect entity [properties] ? -** 28-05-2004

PM this code can work in most of the mod but not DoD, since bot in DoD can't see any w_sub_flag.mdl, they(allies and axis) only can see one model name w_flag.mdl.

DoD team use the properties function to let client show the right flag model only after you captured it.

Cpl. Shrike · **Re: How to detect entity [properties] ? -** 31-05-2004

You have to dinamicaly store the flags state during gameplay.
Don't scan the flag but catch the dod net message "CapMsg"
Store the value then let the bots check that value when it sees that flag.

"CapMsg" has 2 important variables.
the flags name (location)
the team it's owned by.

Those to variables are enuf to store the owner to the flag location.