Monkey-X - Rotating platforms and player - code example

Here a example of how you can have rotating platforms in platformer games. The alignment of the player on a rotating platform is not quite fixed yet but maybe I will find the fix.

Code below :

Import mojo

Const tilewidth = 32
Const tileheight = 32
Const mapwidth:Int=20
Const mapheight:Int=10
Global map:Int[][] = [      [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1],
                            [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
                            [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
                            [1,0,1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
                            [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
                            [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
                            [1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
                            [1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1],
                            [1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,1,1,1,1],
                            [1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1] ]

Class players
    Field x:Float = 640/2-16
    Field y:Float = 480/2
    Field pw:Int=32
    Field ph:Int=32
    Field incy:Float
    Field jump:Bool=False
    Method New()
    End Method
    Method update()
        playermovement
        playergravity
    End Method
    Method playergravity()
        ' If the player is on the ground and the space bar is pressed
        If jump = False And playertc(0,1) = False And colrp(0,1,False) = False
            jump = True
            incy = 0
            For Local i:=Eachin rotplat
                i.lockplayer=False
            Next            
        End If
        If jump = False And KeyDown(KEY_SPACE) = True
            incy = -4
            jump = True
            For Local i:=Eachin rotplat
                i.lockplayer=False
            Next
        End
        'If the player is in the jump
        If jump = True
            incy += 0.1
            'if the player is going up
            If incy <=0
                For Local i:Int = 0 Until Abs(incy)                
                    y -= 1
                    If playertc(0,-1) = True
                        incy = 0
                        Exit
                    End If
                End
            End
            ' if the player if going down
            If incy > 0
                For Local i:Int = 0 Until incy
                    y += 1
                    'if the player touches the ground
                    If playertc(0,1) = True
                        jump = False                        
                        Exit
                    End
                    'if the player lands on a rotating platform
                    If colrp(0,1,True) = True
                        jump = False
                        Exit
                    End If
                End
            End
        End
    End Method
    Method playermovement()
       If KeyDown(KEY_RIGHT)
           For Local i=0 Until 2
            If playertc(1,0) = False
                   x+=1
            End If
           Next
       End If
       If KeyDown(KEY_LEFT)
           For Local i=0 Until 2    
               If playertc(-1,0) = False
                   x-=1
               End If
           Next
       End If
       'if locked to rotating platform then modify position
       For Local i:=Eachin rotplat
               If i.lockplayer = True 
                   y=i.py-ph
                   x+=i.px-i.lx
               End If
       Next        
    End Method
    Method playertc:Bool(x1:Int,y1:Int)
        Local cx = (x + x1) / tilewidth
           Local cy = (y + y1) / tileheight
        For Local y2=cy-1 Until cy+2
        For Local x2=cx-1 Until cx+2
            If x2>=0 And x2<mapwidth And y2>=0 And y2<mapheight
                If map[y2][x2] > 0
                    If rectsoverlap(x+x1,y+y1,pw,ph,x2*tilewidth,
                                    y2*tileheight,tilewidth,tileheight) = True
                        Return True
                    End If
                End If
            End If
        Next
        Next
        Return False
    End Method
    Method colrp:Bool(x1:Int,y1:Int,set:Bool=False) 'player colide with rotating platforms
        For Local i:=Eachin rotplat
            If rectsoverlap(x+x1,y+y1+ph,pw,1,i.px,i.py,i.pw,1) = True Then
                If set=True Then i.lockplayer = True
                Return True
            End If
        Next
        Return False
    End Method
    Method draw()
        ' draw the player
        SetColor 255,255,0        
        DrawOval x,y,pw,ph        
    End Method
End Class

Class rotatingplatforms
    Field x:Float,y:Float,angle:Int
    Field px:Float,py:Float,pw:Int=32,ph:Int=12
    Field lx:Float
    Field lockplayer:Bool=False
    Method New(x:Float,y:Float,angle:Int)
        Self.x = x
        Self.y = y
        Self.angle = angle
    End Method
    Method update()
        angle+=1
        If angle>360 Then angle=angle-360
        If angle<0 Then angle=angle+360
        lx = px
        px = x+(Cos(angle)*64)
        py = y+(Sin(angle)*64)
    End Method
    Method draw()        
        SetColor 255,255,255
        DrawRect px,py,pw,ph
    End Method    
End Class

Global player:List<players> = New List<players>
Global rotplat:List<rotatingplatforms> = New List<rotatingplatforms>

Class MyGame Extends App
    Method OnCreate()
        SetUpdateRate(60)
        player.AddLast(New players())
        rotplat.AddLast(New rotatingplatforms(10*tilewidth,5*tileheight,0))
        rotplat.AddLast(New rotatingplatforms(10*tilewidth,5*tileheight,(360/3)*1))
        rotplat.AddLast(New rotatingplatforms(10*tilewidth,5*tileheight,(360/3)*2))                
    End
    Method OnUpdate()
        ' Player left and right movement
        For Local i:=Eachin player
            i.update
        Next
        For Local i:=Eachin rotplat
            i.update
        Next
    End
    Method OnRender()
        Cls(0,0,0)
        SetColor(255,255,255)
        ' draw the map
        For Local y:Int = 0 Until mapheight
        For Local x:Int = 0 Until mapwidth
            If map[y][x] = 1 Then DrawRect(x*tilewidth,y*tileheight,tilewidth,tileheight)
        End
        End
        DrawText "Platformer Example",10,10
        DrawText "Use cursor left/right and space bar",160,10
        For Local i:=Eachin rotplat    
            i.draw
        Next
        For Local i:=Eachin player
            i.draw
        Next
    End
End



Function rectsoverlap:Bool(x1:Int, y1:Int, w1:Int, h1:Int, x2:Int, y2:Int, w2:Int, h2:Int)
    If x1 > (x2 + w2) Or (x1 + w1) < x2 Then Return False
    If y1 > (y2 + h2) Or (y1 + h1) < y2 Then Return False
    Return True
End

Function Main()
    New MyGame()
End