Game Mechanics

From GPWiki

One thing I noticed on the Wanted Page was a topic on Game Mechanics, the user Primetime requesting how to do fundamental RPG things, like turn-based combat similar to Final Fantasy, and how to calculate damage, etc.

This is a stub because I don't want to be the only one writing this. Let's add formulas that others can use as a basis for their RPG. I'm in the process of making an RPG with friends from school, so I'm willing to share what mathematic and game knowledge in this stub.

Overview of an RPG

RPG or Role-Playing Game is where you as the player takes the role of a character inside of a fictional story, determining how they level up, what dialog actions they take, and how you move the story along.

A classic RPG, such as Final Fantasy, has monsters on one of the battle screen, and the party on the other side. Ever since FFII, Square had implemented ATB combat, Action-Time-Based. This was how quickly characters would act depended on their Speed. In FFIV, the bar was invisible, but in FFVI, the bar was visible. When this bar filled up, the character would flash, and a menu would appear. Then the player could input the commands.

RPGs have all types of attacks, usually divided into physical and magical, so just as common they have similar character stats like Physical Attack and Defense, and Magic Attack and Defense.

The Character Class in an RPG

Creating a class for the character is recommended, because you can hold all of the character's stats inside of the class. Also, you can have private subroutines to determine how HP and other stats are calculated based off of items and attributes.

Class Hero
     Dim Strength as Integer
     Dim Intellect as Integer
     Dim Agility as Integer
     Dim HitPoints as Integer
     Dim Attack as Integer

Here we can see the basic attributes of a hero. How strong he is, how smart he is, how fast he is, how much he can take, and how much he can dish out. It is possible to code an RPG with just these elements, but we're forgetting about other factors that take place inside of an RPG, such as:

1. Dodging
2. Critcals
3. Magic Attack and Defense

But we can attack this later.

Turn-Based Action

Since the RPG I'm coding is a one-man-against-all, I'm only going to code for one character. This routine can be duplicated for multiple characters, and you can queue whose turn it is.

Private Sub Encounter(ByVal Hero.Agility, ByVal Monster.Agility)
     Dim Roll as New Random
     If Hero.Agility + Roll.Next(-6,7) > Monster.Agility
          Call PartyTurn
     Else
          Call EnemyTurn
     End If
End Sub
 
Private Sub EnemyTurn()
     Finished = False
     'Execute the AI or just have the monster do a basic attack
     'After the monster has done it's attack, then set a boolean Finished to true
     If Finished = True
          Call PartyTurn
     EndIf
End Sub
 
Private Sub PartyTurn()
     Finished = False
     CombatMenu.Show
     Select Case CombatMenu.SelectedAction
          Case "Fight"
               Damage = Hero.Attack - Monster.Defense
               If Roll.Next(1,101) < Monster.DodgeChance
                    LabelDamage.Text = "Miss"
                    Damage = 0
               Else
                    LabelDamage.Text = Damage
                    Monster.HitPoints = Monster.HitPoints - Damage
               EndIf
          Case "Spell"
               SpellMenu.Show
               'going to end that there for now
          Case "Defend"
               Hero.Defense = Hero.Defense * 1.5
          Case "Item"
               ItemMenu.Show
               'Same with spell
     End Select
     Finished = True
     If Finished = True
          Call Monster.Turn
     End If
End Sub

At the beginning, when there is an encounter, the Random will pick numbers between -6 and 6 and add it to the player's Agility. This will create more dynamic situations, where sometimes the monster will go first, and other times the player will go first. It balances the playing field so slower, more powerful knights clad in armor or old, vulnerable wizards can get the first go if they get a positive, and a speedy thief can be caught off-guard, and thus lose any superior agility bonuses from that random.

So because at the end of each subroutine it calls the other subroutine, then it will go back and forth. When either side does an action, it sets the boolean Finished to true, then calls the other team's subroutine.