; PhysicsBodyBox Example
; ----------------------
; Requires Extended mode.

Graphics3D 640,480,0,2
SetBuffer BackBuffer()

Const PHYSICS_STATIC=0
Const PHYSICS_DYNAMIC=2

SeedRnd MilliSecs()

camera=CreateCamera()
PositionEntity camera,0,3,-9

light=CreateLight()
RotateEntity light,45,-30,0
AmbientLight 50,50,50

; Independent Box3D world with Earth-like gravity
world=CreatePhysicsWorld()
PhysicsGravity world,0,-9.81,0

; Blue static ground slab - dimensions are full metres
ground=CreateCube()
ScaleEntity ground,4,0.5,4
PositionEntity ground,0,-0.5,0,True
EntityColor ground,80,160,255
ground_body=CreatePhysicsBody(world,ground,PHYSICS_STATIC)
ground_shape=PhysicsBodyBox(ground_body,8,1,8,0)

; Orange tumbling crate with a matching box shape
size#=1
crate=CreateCube()
ScaleEntity crate,size/2,size/2,size/2
PositionEntity crate,0,3,0,True
EntityColor crate,255,120,70
crate_body=CreatePhysicsBody(world,crate,PHYSICS_DYNAMIC)
crate_shape=PhysicsBodyBox(crate_body,size,size,size,1)

While Not KeyDown(1)

    ; Keys 1/2/3 rebuild the box shape with new full dimensions
    new_size#=0
    If KeyHit(2) Then new_size=0.6
    If KeyHit(3) Then new_size=1.0
    If KeyHit(4) Then new_size=1.6
    If new_size>0
        size=new_size
        FreePhysicsShape crate_shape
        crate_shape=PhysicsBodyBox(crate_body,size,size,size,1)
        ; Match the visual cube to the collision size
        ScaleEntity crate,size/2,size/2,size/2
    EndIf

    ; Space tosses the crate up with a random tumble
    If KeyHit(57)
        PhysicsBodyVelocity crate_body,0,6,0
        PhysicsBodyAngularVelocity crate_body,Rnd(-3,3),Rnd(-3,3),Rnd(-3,3)
    EndIf

    ; Advance the Box3D simulation by one 60 Hz step
    StepPhysics world,1.0/60.0,4

    ; Respawn the crate if it tumbles off the slab
    If EntityY(crate)<-8
        FreePhysicsBody crate_body
        PositionEntity crate,0,3,0,True
        RotateEntity crate,0,0,0
        crate_body=CreatePhysicsBody(world,crate,PHYSICS_DYNAMIC)
        crate_shape=PhysicsBodyBox(crate_body,size,size,size,1)
    EndIf

    ; Arrow keys move the camera
    If KeyDown(200) Then MoveEntity camera,0,0,0.1
    If KeyDown(208) Then MoveEntity camera,0,0,-0.1
    If KeyDown(203) Then TurnEntity camera,0,1,0
    If KeyDown(205) Then TurnEntity camera,0,-1,0

    RenderWorld

    Text 0,0,"Arrow keys: camera   1/2/3: box size   Space: toss   Esc: exit"
    Text 0,20,"Box shape: "+size+" x "+size+" x "+size+" m   handle: "+crate_shape

    Flip

Wend

FreePhysicsWorld world
FreeEntity crate
FreeEntity ground
End