'----Includes----'
Import box2d.dynamics.b2world

'----Test Zone----'
Function Main()
  New Box2DLoop()
End Function

'----Main Loop----'
Class Box2DLoop Extends App

  Field _world:b2World

  Field RATIO:Float = 8

  Field _nextCrateIn:Int

  '--Main Methods----'

  Method OnCreate()

    ' 1. Set Up World
    setupWorld()
    ' Create Walls and Floors
    createWallsAndFloor()
    setupDebugDraw()
    _nextCrateIn = 0

    'Display Setup
    SetUpdateRate(60)

  End Method

  Method setupDebugDraw:Void()

      'Box2D Debug Settings       'Delete this section if you dont need to see the physical process in graphics.
    Local dbgDraw :b2DebugDraw = New b2DebugDraw()      

        dbgDraw.SetDrawScale(10.0)
        dbgDraw.SetFillAlpha(0.3)
        dbgDraw.SetLineThickness(1.0)
        dbgDraw.SetFlags(b2DebugDraw.e_shapeBit | b2DebugDraw.e_jointBit)'| b2DebugDraw.e_pairBit)
        _world.SetDebugDraw(dbgDraw)

  End
  Method OnRender()
    Cls    

    _world.DrawDebugData()

  End Method

  Method OnUpdate()

    _world.TimeStep(1.0 /30,10,10)
    _world.ClearForces()

    _nextCrateIn = _nextCrateIn - 1

    If _nextCrateIn  <=0 And _world.m_bodyCount < 80 Then
      addARandomCrate()
      _nextCrateIn = 10
    Endif

  End Method

  Method setupWorld()

    ' Define gravity
    Local gravity:b2Vec2 = New b2Vec2(0,9.8)

    ' Ignore Sleeping Objects
    Local ignoresleeping:Bool = True

    _world = New b2World(gravity,ignoresleeping)

  End

  Method addARandomCrate()
    Local fd:b2FixtureDef = New b2FixtureDef()
    Local sd:b2PolygonShape = New b2PolygonShape()
    Local bd:b2BodyDef = New b2BodyDef();
    bd.type = b2Body.b2_Body

    fd.friction = 0.8
    fd.restitution = 0.3
    fd.density = 0.7
    fd.shape = sd

    sd.SetAsBox(randomInt(5,40) / RATIO, randomInt(5, 40) / RATIO)

    bd.position.Set(randomInt(15,530) / RATIO, randomInt(-100, -10) / RATIO)
    bd.angle = randomInt(0,360) * 3.14 / 180

    Local b:b2Body = _world.CreateBody(bd)
    b.CreateFixture(fd)

  End

  Method randomInt:Int(lowVal:Int, highVal:Int)

    If (lowVal <= highVal)

      Return lowVal + Floor(Rnd() * (highVal - lowVal + 1))

    Endif
  End

  Method createWallsAndFloor:Void()

    Local sd:b2PolygonShape = New b2PolygonShape()
    Local fd:b2FixtureDef = New b2FixtureDef()
    Local bd:b2BodyDef = New b2BodyDef()
    bd.type = b2Body.b2_staticBody

    sd.SetAsArray([New b2Vec2(0,0),New b2Vec2(550/RATIO,0), New b2Vec2(550/RATIO,10/RATIO), New b2Vec2(0,10/RATIO)])

    fd.friction = 0.5
    fd.restitution = 0.3
    fd.density = 0.0
    fd.shape = sd

    bd.position.Set(0,560/RATIO)

    Local b:b2Body = _world.CreateBody(bd)
    b.CreateFixture(fd)

    Local sdwall:b2PolygonShape = New b2PolygonShape()
    Local fdwall:b2FixtureDef = New b2FixtureDef()
    Local bdwall:b2BodyDef = New b2BodyDef()   
    bd.type = b2Body.b2_staticBody

    fdwall.friction =  0.5
    fdwall.restitution = 0.3
    fdwall.density = 0
    fdwall.shape = sdwall
    sdwall.SetAsBox(5/RATIO,390/RATIO)

    bdwall.position.Set(5/RATIO,195/RATIO)

    Local leftwall:b2Body = _world.CreateBody(bdwall)
    leftwall.CreateFixture(fdwall)

    bdwall.position.Set(545/RATIO,195/RATIO)

    Local rightwall:b2Body = _world.CreateBody(bdwall)
    rightwall.CreateFixture(fdwall)

  End
End Class