.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "gallery/offsceen_threaded.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_gallery_offsceen_threaded.py>`
        to download the full example code.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_gallery_offsceen_threaded.py:


Offscreen threaded
------------------

Example that renders frames in a separate thread.

This uses an offscreen canvas, the result is only used to print the
frame shape. But one can see how one can e.g. render a movie this way.

Threaded rendering using a real GUI is not supported right now, since
this is tricky to do with both Qt and glfw. Plus in general its a bad
idea to run your UI in anything other than the main thread. In other
words, you should probably only use threaded rendering for off-screen
stuff.

.. GENERATED FROM PYTHON SOURCE LINES 17-56

.. code-block:: Python


    # test_example = true

    import time
    import threading

    from rendercanvas.offscreen import RenderCanvas

    from rendercanvas.utils.cube import setup_drawing_sync


    # create canvas
    canvas = RenderCanvas()
    draw_frame = setup_drawing_sync(canvas)


    def main():
        frame_count = 0
        canvas.request_draw(draw_frame)

        while not canvas.get_closed():
            image = canvas.draw()
            frame_count += 1
            print(f"Rendered {frame_count} frames, last shape is {image.shape}")


    if __name__ == "__main__":
        t1 = threading.Thread(target=main)
        t1.start()

        # In the main thread, we wait a little
        time.sleep(1)

        # ... then change the canvas size, and wait some more
        canvas.set_logical_size(200, 200)
        time.sleep(1)

        # Close the canvas to stop the tread
        canvas.close()


.. _sphx_glr_download_gallery_offsceen_threaded.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: offsceen_threaded.ipynb <offsceen_threaded.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: offsceen_threaded.py <offsceen_threaded.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: offsceen_threaded.zip <offsceen_threaded.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_