; EntityInView Example
; --------------------

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

camera=CreateCamera()
PositionEntity camera,0,2,-10

light=CreateLight()
RotateEntity light,45,45,0

; Textured ground plane
plane=CreatePlane()
ground_tex=LoadTexture("media/MossyGround.BMP")
ScaleTexture ground_tex,4,4
EntityTexture plane,ground_tex

; A patrol drone flies left and right, crossing the edges of the camera's view
drone=CreateSphere()
PositionEntity drone,0,2,5

angle#=0

While Not KeyDown(1)

    ; Patrol far beyond both screen edges
    angle=angle+1
    PositionEntity drone,Sin(angle)*20,2,5

    ; 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

    ; Ask the camera whether the drone is inside its view frustum
    in_view=EntityInView(drone,camera)

    ; Green while visible, red while outside the view (seen as it re-enters)
    If in_view Then EntityColor drone,50,255,50 Else EntityColor drone,255,50,50

    RenderWorld

    Text 0,0,"Arrow keys: move camera   Esc: exit"
    If in_view Then
        Text 0,20,"EntityInView(drone,camera) = 1  - the drone is on screen"
    Else
        Text 0,20,"EntityInView(drone,camera) = 0  - the drone has left the view"
    EndIf

    Flip

Wend

End