A_JumpIfInventory

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A_JumpIfInventory (string inventorytype, int amount, int offset)
A_JumpIfInventory (string inventorytype, int amount, str state)

Warning: Using state labels as arguments without quotation marks has been deprecated and will no longer work. Make sure to enclose all your string arguments with quotation marks to ensure full compatibility with future ZDoom versions. Refer to the available example(s) for proper usage

Checks the amount of inventorytype items in the actor's inventory. If there are at least amount, the jump is performed. The offset parameter specifies how many frames ahead to jump.

Note that if amount is 0, the jump is only performed if the actor is carrying the maximum number of that item. This is useful for checking whether the player has the maximum amount of ammo for a particular weapon, regardless of whether or not he's found a backpack.

Examples

Here's a shotgun with a Counterstrike (or whatever the hell you want to call it)-style reloading system.

ACTOR DukeShotgun : Weapon 22009       //The shotgun from Duke Nukem 3D. The newly added   
{                                        reloading state is mostly finished. Although this
   Weapon.AmmoType "InsertedShell"       state is effective, it also continues if there are no 
   Weapon.AmmoType2 "Shell"              shells in your inventory. It'll be fixed.
   Weapon.AmmoGive 0
   Weapon.AmmoGive2 30 
   Weapon.AmmoUse 1
   Scale 0.625
   Inventory.PickupSound "misc/w_pkup" 
   Inventory.PickupMessage "Shotgun!"
   ATTACKSOUND "duke/shotgun"
   OBITUARY "%o got punctured with Duke's Shotgun."
   states 
   { 
   Spawn: 
       SHG3 A 1 
       Loop 
   Ready: 
       SHT3 A 1 A_WeaponReady 
       Loop 
   DeSelect: 
       SHT3 A 1 A_Lower 
       Loop 
   Select: 
       SHT3 A 1 A_Raise 
       Loop 
   Fire: 
       SHT3 A 2 A_Gunflash 
       SHT3 F 2 A_FireBullets(2,1,8,4)
       SHT3 KFABCD 3
       SHT3 E 5 A_FireCustomMissile("ShotgunShell",90,0)
       SHT3 DCB 4
       SHT3 A 6 A_JumpIfNoAmmo(2) 
       SHT3 A 0 A_Refire
       Goto Ready
       SHT3 GH 3                                        //This creates a reloading state which
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,39)  replaces any used shells with new
       SHT3 I 3 A_TakeInventory("Shell",1)                ones. For example: if you have 4 out
       SHT3 J 0 A_PlaySound("weapons/sshotl")             of 10 shells, this will give you 6, 
       SHT3 J 3 A_GiveInventory("InsertedShell",1)        not 10. 
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,35)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,31)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,27)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,23)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,19)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,15)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,11)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,7)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,3)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 HG 4
       Goto Ready
   Flash:
       SH3F AB 2 BRIGHT
       Stop
   AltFire:                                   //The reloading state, but can be done manually.
       SHT3 GH 3 
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,39)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,35)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,31)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,27)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,23)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,19)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,15)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,11)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,7)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 J 0 A_JumpIfInventory("InsertedShell",10,3)
       SHT3 I 3 A_TakeInventory("Shell",1)
       SHT3 J 0 A_PlaySound("weapons/sshotl")
       SHT3 J 3 A_GiveInventory("InsertedShell",1)
       SHT3 HG 3
       Goto Ready     
   }
}