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(use-modules (chickadee)
(chickadee math rect)
(chickadee math vector)
(chickadee render)
(chickadee render color)
(chickadee render font)
(chickadee render particles)
(chickadee render sprite)
(chickadee render texture)
(chickadee scripting)
(ice-9 format)
((sdl2) #:select (sdl-ticks)))
(define window-width 800)
(define window-height 600)
(define particles #f)
(define emitter #f)
(define particle-texture #f)
(define sprite-texture #f)
(define start-time (sdl-ticks))
(define avg-frame-time 0)
(define stats-text "")
(define (center-x w)
(- (/ window-width 2.0) (/ w 2.0)))
(define (center-y h)
(- (/ window-height 2.0) (/ h 2.0)))
(define (load)
(set! *random-state* (random-state-from-platform))
(set! particle-texture (load-image "images/explosion.png"))
(set! sprite-texture (load-image "images/chickadee.png"))
(set! particles (make-particles 2000
#:texture particle-texture
#:end-color (make-color 1.0 1.0 1.0 0.8)
#:end-color (make-color 1.0 1.0 1.0 0.0)
#:speed-range (vec2 1.0 5.0)
;;#:acceleration-range (vec2 -0.1 -0.2)
#:lifetime 40
#:animation-columns 12
#:sort 'young))
(set! emitter (make-particle-emitter (make-rect (center-x 0.0)
(center-y 0.0)
0.0 0.0)
8))
(add-particle-emitter particles emitter)
(script
(forever
(sleep 60)
(set! stats-text (format #f "particles: ~d fps: ~1,2f"
(particles-size particles)
(/ 1000.0 avg-frame-time))))))
(define stats-text-pos (vec2 4.0 (- window-height 16.0)))
(define sprite-position (vec2 (center-x 128.0) (center-y 128.0)))
(define (draw alpha)
(draw-particles particles)
(draw-sprite sprite-texture sprite-position)
(draw-text stats-text stats-text-pos)
(let ((current-time (sdl-ticks)))
(set! avg-frame-time
(+ (* (- current-time start-time) 0.1)
(* avg-frame-time 0.9)))
(set! start-time current-time)))
(define (update dt)
(update-agenda 1)
(update-particles particles))
(define (mouse-move x y dx dy buttons)
(let ((area (particle-emitter-spawn-area emitter)))
(set-rect-x! area x)
(set-rect-y! area y)
(set-vec2! sprite-position (- x 64.0) (- y 64.0))))
(run-game #:load load
#:draw draw
#:update update
#:mouse-move mouse-move
#:window-width window-width
#:window-height window-height)
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