; ParticleCollision Example
; -------------------------
; Requires Extended mode.

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

camera=CreateCamera()
PositionEntity camera,0,2,-6
CameraClsColor camera,8,12,24

; A Box3D physics world with a static slab for particles to bounce on
world=CreatePhysicsWorld()
slab=CreateCube()
ScaleEntity slab,3,0.25,3
PositionEntity slab,0,0.25,0
EntityColor slab,55,60,72
slab_body=CreatePhysicsBody(world,slab,0)
slab_shape=PhysicsBodyBox(slab_body,6,0.5,6,0)

; Sparks raining down onto the slab
emitter=CreateParticleEmitter(600)
PositionEntity emitter,0,3.5,0
ParticlePreset emitter,4
ParticleEmissionRate emitter,120
ParticleGravity emitter,0,-6,0

; Enable swept collision against the physics world
ParticleCollision emitter,world,0.04,0.65,0.15
colliding=True

While Not KeyDown(1)

    ; Space toggles collision - pass zero as the world to disable it
    If KeyHit(57)
        colliding=Not colliding
        If colliding
            ParticleCollision emitter,world,0.04,0.65,0.15
        Else
            ParticleCollision emitter,0,0,0,0
        EndIf
    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

    ; UpdateWorld also advances the particle simulation
    UpdateWorld
    RenderWorld

    Text 0,0,"Arrow keys: move camera   Space: toggle collision   Esc: exit"
    If colliding Then state$="ParticleCollision emitter,world,0.04,0.65,0.15 (sparks bounce)" Else state$="ParticleCollision emitter,0,0,0,0 (sparks fall through)"
    Text 0,20,state$

    Flip

Wend

FreePhysicsWorld world
End