Monkey-X - Turrets and Zombies - code example

Import mojo

Class bullet
    ' bullet x and y and radius
    Field bx:Float,by:Float,br:Int=4
    Field angle:Int
    Field bulletspeed:Float=3
    Field bulletmaxdist:Int=1200
    Field bullettraveled:Int
    Field deleteme:Bool=False
    ' start location and target location for getting angle
    Method New(x1:Int,y1:Int,x2:Int,y2:Int)
        bx = x1
        by = y1
        angle = getangle(x1,y1,x2,y2)
    End Method
    Method update()
        ' update the bullet position
        bx += Cos(angle)*bulletspeed
        by += Sin(angle)*bulletspeed
        ' if distance to long then flag bullet for removal
        bullettraveled+=1
        If bullettraveled > bulletmaxdist Then deleteme = True
        ' check collision with zombies
        For Local i:=Eachin myzombie
            If circleoverlap(bx,by,br,i.zx,i.zy,i.zr)
                deleteme = True
                i.hitpoints-=1
                ' Bounce them a bit back
                i.zx += Cos(angle+Rnd(-20,20))*Rnd(5,13)
                i.zy += Sin(angle+Rnd(-20,20))*Rnd(5,13)
                i.flash = True
                ' If they are dead then flag them
                If i.hitpoints<=0 Then
                    i.deleteme = True
                End If
            End If
        Next
    End Method
    Method draw()
        SetColor 255,255,0
        DrawCircle bx,by,br
    End Method
End Class

Class turret
    ' turret x and y and radius
    Field tx:Int,ty:Int,tr:Int=16
    Field targetx:Int,targety:Int
    Field deleteme:Bool=False
    Field shootdelay:Int
    Field maxshootdelay:Int=10
    Field currentangle:Int,shootangle:Int
    Field notarget:Bool=True
    Field turnspeed:Int=3 'turn speed of the turret
    Field shakex:Int,shakey:Int
    Field shaketime:Int
    Method New(x:Int,y:Int)
        tx = x
        ty = y
        turnspeed = Rnd(1,10)
    End Method
    Method update()
        shootdelay += 1
        ' shooting here
        ' check if there are zombies on the map
        If Not myzombie.IsEmpty             
            Local ntx:Int,nty:Int  ' New target x And y
            Local sdist:Int=1000 'shortest distance
            ' find zombie closest to turret
            For Local i:=Eachin myzombie
                Local d:Int=distance(tx,ty,i.zx,i.zy)
                If d<sdist Then
                    sdist = d
                    ntx = i.zx
                    nty = i.zy
                End If
            Next
            shootangle = getangle(tx,ty,ntx,nty)            
            targetx = ntx
            targety = nty
            notarget = False
            Else
            notarget = True
        End If

        'if we have a target
        If notarget = False Then
            'turn the turrent to target
            For Local i:=0 Until turnspeed
                If currentangle <> shootangle
                    currentangle += turndirection(shootangle)
                    If currentangle>180 Then currentangle = -180
                    If currentangle<-180 Then currentangle = 180
                End If
            Next
            ' if we are aimed and reloaded then shoot
            If shootdelay > maxshootdelay
                shootdelay = 0 
                If currentangle = shootangle
                    ' add a shake in the opposite direction
                    ' of the barrel.
                    shakex = -Cos(currentangle)*2
                    shakey = -Sin(currentangle)*2
                    shaketime = 4
                    mybullet.AddLast(New bullet(tx+Cos(shootangle)*16,ty+Sin(shootangle)*16,targetx,targety))
                End If
            End If
        End If
    End Method
    ' returns -1(left) or 1 right to turn towards the closest turn
    Method turndirection(destangle:Int)
        Local myangle:Int=currentangle
        Local d1:Int
        'turn left
        While myangle <> destangle
            myangle-=1
            If myangle<-180 Then myangle = 180
            d1+=1
        Wend
        myangle = currentangle
        Local d2:Int
        While myangle <> destangle
            myangle+=1
            If myangle>180 Then myangle = -180
            d2+=1
        Wend
        If d2>d1 Then Return -1 Else Return 1
    End Method
    Method draw()
        Local tx:Int = tx+shakex
        Local ty:Int = ty+shakey
        shaketime-=1
        If shaketime < 0 Then shakex = 0 ; shakey = 0
        SetColor 0,255,255
        DrawCircle tx,ty,tr
        Local x2:Int,y2:Int
        x2 = Cos(currentangle)*20
        y2 = Sin(currentangle)*20
        DrawCircle tx+x2,ty+y2,10
    End Method
End Class

Class zombie
    ' zombie x and y and radius
    Field zx:Float,zy:Float,zr:Int=16
    Field tx:Int,ty:Int
    Field angle:Int
    Field movementspeed:Float=.5
    Field deleteme:Bool=False
    Field hitpoints:Int
    Field flash:Bool=False
    Field flashtime:Int
    Method New(x:Int,y:Int)
        zx = x
        zy = y
        hitpoints = Rnd(1,4)
        If Rnd(100)<2 Then hitpoints*=5
        movementspeed = Rnd(0.1,0.3)
    End Method
    Method update()
        If Not myturret.IsEmpty 
            Local ntx:Int,nty:Int
            Local cdist:Int=1000
            For Local i:=Eachin myturret
                Local d:Int=distance(zx,zy,i.tx,i.ty)
                If d<cdist
                    d = cdist
                    ntx = i.tx
                    nty = i.ty
                End If
            Next
            tx = ntx
            ty = nty
            angle = getangle(zx,zy,ntx,nty)             
        End If
        'move the zombie
        zx += Cos(angle) * movementspeed
        zy += Sin(angle) * movementspeed
    End Method
    Method draw()
        If flash = False
            SetColor 255,0,0
            flashtime = 4
            Else
            SetColor 255,255,255
            flashtime -= 1
            If flashtime < 0 Then flash = False
        End If
        DrawCircle zx,zy,zr
    End Method
End Class

Global myturret:List<turret> = New List<turret>
Global myzombie:List<zombie> = New List<zombie>
Global mybullet:List<bullet> = New List<bullet>

Class MyGame Extends App

    Method OnCreate()
        Seed = GetDate[4] + GetDate[5]
        SetUpdateRate(60)
        myturret.AddLast(New turret(DeviceWidth/2,DeviceHeight/2))
        myturret.AddLast(New turret(DeviceWidth/2-50,DeviceHeight/2))
        myturret.AddLast(New turret(DeviceWidth/2+50,DeviceHeight/2))

    End Method
    Method OnUpdate()        
        ' If press space then reset level
        If KeyHit(KEY_SPACE) Or MouseHit(MOUSE_LEFT) Then restart()
        'update the turrents zombies and bullets
        For Local i:=Eachin myturret
            i.update()
        Next
        For Local i:=Eachin myzombie
            i.update()
        Next
        For Local i:=Eachin mybullet
            i.update()
        Next
        ' remove any that are gone
        For Local i:=Eachin myturret
            If i.deleteme = True Then myturret.Remove(i)
        Next
        For Local i:=Eachin myzombie
            If i.deleteme = True Then myzombie.Remove(i)
        Next
        For Local i:=Eachin mybullet
            If i.deleteme = True Then mybullet.Remove(i)
        Next
        ' add zombies to the map
        If Rnd(200)<5 Then addzombie(DeviceWidth,DeviceHeight)
        '
    End Method
    Method OnRender()
        Cls 0,0,0 

        For Local i:=Eachin myturret
            i.draw()
        Next
        For Local i:=Eachin myzombie
            i.draw()
        Next
           For Local i:=Eachin mybullet
            i.draw()
        Next


        SetColor 255,255,255
        DrawText "Zombies and Turrent - Press Space/Mouse to reset map",0,0
    End Method
End Class

Function restart()
    myturret = New List<turret>
    myzombie = New List<zombie>
    mybullet = New List<bullet>
    myturret.AddLast(New turret(DeviceWidth/2,DeviceHeight/2))
    myturret.AddLast(New turret(DeviceWidth/2-50,DeviceHeight/2))
    myturret.AddLast(New turret(DeviceWidth/2+50,DeviceHeight/2))
End Function

Function addzombie(Width:Int,Height:Int)
    Local l:Int=Rnd(4)
    Local x:Int,y:Int
    Select l
    Case 0
    x = 0
    y = Rnd(Height)
    Case 1
    x = Width
    y = Rnd(Height)
    Case 2
    x = Rnd(Width)
    y = 0
    Case 3
    x = Rnd(Width)
    y = Height
    End Select
    myzombie.AddLast(New zombie(x,y))
End Function

Function Main()
    New MyGame()
End Function

Function distance:Int(x1:Int,y1:Int,x2:Int,y2:Int)
    Return Abs(x2-x1)+Abs(y2-y1)
End Function

Function getangle:Int(x1:Int,y1:Int,x2:Int,y2:Int)
    Local dx = x2 - x1
    Local dy = y2 - y1
    Return ATan2(dy,dx)+360 Mod 360
End Function 

Function circleoverlap:Bool(x1:Int,y1:Int,r1:Int,x2:Int,y2:Int,r2:Int)
    Local dx:Int = x1-x2
    Local dy:Int = y1-y2
    Local r:Int = r1+r2
    If dx*dx+dy*dy <= r*r Then Return True Else Return False
End