In OnPlayerDamage(Entity player, Entity inflictor, Entity attacker, int damage, int dFlags, string mod, string weapon, Vector3 point, Vector3 dir, string hitLoc) who is inflictor and also what is dflags,point and dir?

The entity that causes the damage.(e.g. a turret)

Integer specifying flags that are to be applied to the damage

(vector) The direction of the damage

(vector) The point of the damage

So what is attacker?

The entity that is attacking.

 

And the various damage flags:

	// code-defined:
level.iDFLAGS_RADIUS						= 1;	// damage was indirect
level.iDFLAGS_NO_ARMOR						= 2;	// armor does not protect from this damage
level.iDFLAGS_NO_KNOCKBACK					= 4;	// do not affect velocity, just view angles
level.iDFLAGS_PENETRATION					= 8;	// damage occurred after one or more penetrations
level.iDFLAGS_STUN							= 16;	// non-lethal
level.iDFLAGS_SHIELD_EXPLOSIVE_IMPACT		= 32;	// missile impacted on the front of the victim's shield
level.iDFLAGS_SHIELD_EXPLOSIVE_IMPACT_HUGE	= 64;	//   ...and was from a projectile with "Big Explosion" checked on.
level.iDFLAGS_SHIELD_EXPLOSIVE_SPLASH		= 128;	// explosive splash, somewhat deflected by the victim's shield

// script-defined:
level.iDFLAGS_NO_TEAM_PROTECTION			= 256;
level.iDFLAGS_NO_PROTECTION					= 512;
level.iDFLAGS_PASSTHRU						= 1024;

Thanks for your help .Is there any function like ServerSay in InfinityScript?

Thanks for your help .Is there any function like ServerSay in InfinityScript?

Nope, but I think there is another function equivalent, can't check not home atm.