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

.. only:: html

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

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

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

.. _sphx_glr__gallery_events_scatter_click.py:


Scatter click
=============

Add an event handler to click on scatter points and highlight them, i.e. change the color and size of the clicked point.
Fly around the 3D scatter using WASD keys and click on points to highlight them

.. GENERATED FROM PYTHON SOURCE LINES 8-66



.. image-sg:: /_gallery/events/images/sphx_glr_scatter_click_001.webp
   :alt: scatter click
   :srcset: /_gallery/events/images/sphx_glr_scatter_click_001.webp
   :class: sphx-glr-single-img


.. rst-class:: sphx-glr-script-out

 .. code-block:: none

    /opt/hostedtoolcache/Python/3.12.9/x64/lib/python3.12/site-packages/pygfx/objects/_ruler.py:266: RuntimeWarning: divide by zero encountered in divide
      screen_full = (ndc_full[:, :2] / ndc_full[:, 3:4]) * half_canvas_size
    /opt/hostedtoolcache/Python/3.12.9/x64/lib/python3.12/site-packages/pygfx/objects/_ruler.py:266: RuntimeWarning: invalid value encountered in divide
      screen_full = (ndc_full[:, :2] / ndc_full[:, 3:4]) * half_canvas_size
    /opt/hostedtoolcache/Python/3.12.9/x64/lib/python3.12/site-packages/pygfx/objects/_ruler.py:278: RuntimeWarning: invalid value encountered in divide
      screen_sel = (ndc_sel[:, :2] / ndc_sel[:, 3:4]) * half_canvas_size
    /home/runner/work/fastplotlib/fastplotlib/fastplotlib/graphics/features/_base.py:18: UserWarning: casting float64 array to float32
      warn(f"casting {array.dtype} array to float32")







|

.. code-block:: Python


    # test_example = false

    import numpy as np
    import fastplotlib as fpl
    import pygfx

    # make a gaussian cloud
    data = np.random.normal(loc=0, scale=3, size=1500).reshape(500, 3)

    figure = fpl.Figure(cameras="3d", size=(700, 560))

    scatter = figure[0, 0].add_scatter(
        data,  # the gaussian cloud
        sizes=10,  # some big points that are easy to click
        cmap="viridis",
        cmap_transform=np.linalg.norm(data, axis=1)  # color points using distance from origin
    )

    # simple dict to restore the original scatter color and size
    # of the previously clicked point upon clicking a new point
    old_props = {"index": None, "size": None, "color": None}


    @scatter.add_event_handler("click")
    def highlight_point(ev: pygfx.PointerEvent):
        global old_props

        # the index of the point that was just clicked
        new_index = ev.pick_info["vertex_index"]

        # restore old point's properties
        if old_props["index"] is not None:
            old_index = old_props["index"]
            if new_index == old_index:
                # same point was clicked, ignore
                return
            scatter.colors[old_index] = old_props["color"]
            scatter.sizes[old_index] = old_props["size"]

        # store the current property values of this new point
        old_props["index"] = new_index
        old_props["color"] = scatter.colors[new_index].copy()  # if you do not copy you will just get a view of the array!
        old_props["size"] = scatter.sizes[new_index]

        # highlight this new point
        scatter.colors[new_index] = "magenta"
        scatter.sizes[new_index] = 20


    figure.show()


    # NOTE: `if __name__ == "__main__"` is NOT how to use fastplotlib interactively
    # please see our docs for using fastplotlib interactively in ipython and jupyter
    if __name__ == "__main__":
        print(__doc__)
        fpl.loop.run()


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 0.482 seconds)


.. _sphx_glr_download__gallery_events_scatter_click.py:

.. only:: html

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

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

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

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

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

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

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


.. only:: html

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

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