Error with image widget

[shamazmazum]

Hi. I am running common-lisp-jupyter-20211207180130 from Ultralisp on SBCL 2.2.0 and have the following jupyter packages

vasily@vonbraun:~ % pkg info | grep noteb
py38-nbclient-0.5.9            Client library for executing notebooks
py38-notebook-6.4.6            Web-based notebook environment for interactive computing
vasily@vonbraun:~ % pkg info | grep jupyter
py38-jupyter-client-6.1.12_1   Jupyter protocol implementation and client libraries
py38-jupyter-core-4.9.1        Jupyter core package
py38-jupyter-server-1.13.2     The backend to Jupyter web applications
py38-jupyterlab-3.1.14         JupyterLab server extension
py38-jupyterlab-pygments-0.1.2 Pygments theme using JupyterLab CSS variables
py38-jupyterlab-server-2.10.2  JupyterLab Server
py38-jupyterlab-widgets-1.0.2  JupyterLab extension for Jupyter/IPython widgets

The problem is with jupyter-widgets:image widget. I run an example which draws the Julia set. Right after creation of a widget there is no image. I think this is incorrect, because you have (update instance) right at the end of initialize-instance method.

When I press some buttons on other widgets the image is drawn:

but I have this in the console from where jupyter is started:

When I remove this method from src/message.lisp the memory corruption problem is gone. I think it tries to free some foreign memory twice.

(defmethod initialize-instance :after ((instance message) &rest initargs &key &allow-other-keys)
  (declare (ignore initargs))
  (let ((buffers (message-buffers instance)))
    (when buffers
      (trivial-garbage:finalize
        instance
        (lambda () (mapcar (lambda (buffer)
                             (static-vectors:free-static-vector buffer))
                           buffers))))))

But this does not solve the first problem. Practically, I have two image widgets and one integer scroller. When the scroller's value is changed a function is called which redraws both images. The first image is redrawn each time the value of that scroller is changed and the second image is redrawn only occasionally.

[shamazmazum]

My code is here

The result is the following:

Two images must be identical but they are not.

[yitzchak]

This is probably due to bad finalization logic in my use of static-vectors.

Also, for your code sample you just posted a link back to this issue. Can you post at least a snippet of the code that produces the image comparison widget above?

[shamazmazum]

Oh, sorry. Here is a correct link. Those raw files are voxel spaces with dimensions sidexsidexside and one byte per voxel. I attach one so you can play
test.raw.zip

https://gist.github.com/shamazmazum/e3d7e54f3bef21b612ced296057f4f9d