opencv projection matrix animation in hylang. the setup is too slow for realtime animation. I decide I'd abandon the idea to use 2D graphics for pseudo-3D animation. go with 3D graphics library.

multiple-projection-transform-animation.lisp

(import cv2)
(import numpy :as np)
(import matplotlib [pyplot :as plt animation :as plt-anim])

(setv fig (.figure plt))
(setv idxs [] ims [] axs [])


(defn plot [f]
  (print f)
  (.cla plt)
  (for [i idxs]
    (let [im (get ims i) ax (get axs i)
          p-orig (.float32 np  [[0 0] [500 0] [0 1400] [500 1400]])
          p-trans (.float32 np [[0 0] [500 (* f 10)] [0 1400] [500 (- 1400 (* f 10))]])
          mtx (.getPerspectiveTransform cv2 p-orig p-trans)
          im-transformed (.warpPerspective cv2 im mtx #(500 1400))]
    (.imshow ax im-transformed))))

(setv num 4)

(for [i (range 0 num)]
     (let [path (.format "/home/norimixer/quicklisp/local-projects/fusuma/paintings/kiji/{:02}.png" i)
          ax (.add_subplot fig 1 num (- (+ num 1) (+ i 1)))]
       (.append idxs i)
       (.append ims (.imread cv2 path 1))
       (.append axs ax)
       (.set_axis_off ax)))
(setv anim (.FuncAnimation plt-anim fig plot :interval 100 :frames 20))

(.tight_layout fig)
(.subplots_adjust plt :wspace 0 :hspace 0)
(.show plt)
(.close plt)