' GX engine first light: the engine owns no head.  This application owns its
' arrays and emits the ordinary GFX frame after GX advances its state.
IMPORT gx

DIM SHARED Scene(0 TO 7) AS INTEGER
DIM SHARED Entities(0 TO 19) AS INTEGER
DIM SHARED Camera(0 TO 1) AS INTEGER

WINDOW SUB OPEN()
  CALL GXSceneOpen(Scene(), 320, 192)
  CALL GXEntitySpawn(Entities(), 0, 20, 80, 12, 12, 1)
  CALL GXEntityVelocity(Entities(), 0, 2, 0)
  SERVICE SET_TITLE("GX engine first light")
END SUB

WINDOW SUB DRAW()
  DIM X AS INTEGER
  CALL GXSceneAdvance(Scene())
  CALL GXEntityStep(Entities(), 0)
  X = GXEntityX(Entities(), 0)
  IF X > 307 THEN
    CALL GXEntitySpawn(Entities(), 0, 0, 80, 12, 12, 1)
    CALL GXEntityVelocity(Entities(), 0, 2, 0)
    X = 0
  END IF
  CALL GXCameraFollow(Camera(), X, 86, 640, 192, 320, 192)
  INTENT GFX.BEGIN_FRAME()
  INTENT GFX.FILL_RECT(0, 0, 320, 192, 2081)
  INTENT GFX.FILL_RECT(X - GXCameraX(Camera()), 80, 12, 12, -2048)
  INTENT GFX.DRAW_TEXT(12, 12, "GX: caller-owned game state", 3, -1, 2081)
  INTENT GFX.PRESENT()
END SUB

WINDOW SUB CLOSE()
END SUB

ON KEY SUB (K AS INTEGER)
  SERVICE INVALIDATE()
END SUB