(use-modules (chickadee graphics sprite)
	     (chickadee)
	     (chickadee graphics viewport))

(define lane-height 65)
(define lane-length 200)
(define road (load-tileset "road.png" lane-length lane-height))
(define road-top (texture-atlas-ref road 2))
(define road-bottom (texture-atlas-ref road 0))
(define road-lane (texture-atlas-ref road 1))

(define (draw-lanes startx starty num-lanes)
  (if (> num-lanes 0)
      (begin
	(draw-sprite road-lane (vec2 startx starty))
	(draw-lanes startx (+ lane-height starty) (- num-lanes 1)))))

(define (draw-road-section startx starty num-lanes)
  (draw-sprite road-bottom (vec2 startx starty))
  (draw-lanes startx (+ lane-height starty) (- num-lanes 2))
  (draw-sprite road-top (vec2 startx (+ starty (* lane-height (- num-lanes 1))))))

(define (draw-road startx starty num-lanes)
  (if (< startx (window-width (current-window)))
      (begin
	(draw-road-section startx starty num-lanes)
	(draw-road (+ startx lane-length) starty num-lanes))))

(define vehicles (load-tileset "vehicles.png" 100 45))
(define the-car (texture-atlas-ref vehicles 0))
(define car-ref 0)

(define car-pos-x 0.0)
(define car-speed 4.0)

(define (draw alpha)
  ; Draw the road
  (draw-road 0 90 5)

  
  (draw-sprite (texture-atlas-ref vehicles car-ref) (vec2 car-pos-x 100))
  (draw-text "Turbo racers!" (vec2 260.0 240.0))
  (set! car-pos-x (+ car-speed car-pos-x))
  (if (> car-pos-x (window-width (current-window)))
      (begin
	(set! car-pos-x 0.0)
	(if (= car-ref 8)
	    (set! car-ref 0)
	    (set! car-ref (+ 1 car-ref))))))