.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "_gallery/events/lines_mouse_nearest.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_lines_mouse_nearest.py>`
        to download the full example code.

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

.. _sphx_glr__gallery_events_lines_mouse_nearest.py:


Highlight nearest circle
========================

Shows how to use the "pointer_move" event to get the nearest circle and highlight it.

.. GENERATED FROM PYTHON SOURCE LINES 8-62



.. image-sg:: /_gallery/events/images/sphx_glr_lines_mouse_nearest_001.webp
   :alt: lines mouse nearest
   :srcset: /_gallery/events/images/sphx_glr_lines_mouse_nearest_001.webp
   :class: sphx-glr-single-img


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

 .. code-block:: none

    /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

    from itertools import product
    import numpy as np
    import fastplotlib as fpl
    import pygfx


    def make_circle(center, radius: float, n_points: int) -> np.ndarray:
        theta = np.linspace(0, 2 * np.pi, n_points)
        xs = radius * np.cos(theta)
        ys = radius * np.sin(theta)

        return np.column_stack([xs, ys]) + center

    spatial_dims = (100, 100)

    circles = list()
    for center in product(range(0, spatial_dims[0], 15), range(0, spatial_dims[1], 15)):
        circles.append(make_circle(center, 5, n_points=75))

    pos_xy = np.vstack(circles)

    figure = fpl.Figure(size=(700, 560))

    line_collection = figure[0, 0].add_line_collection(circles, colors="w", thickness=5)


    @figure.renderer.add_event_handler("pointer_move")
    def highlight_nearest(ev: pygfx.PointerEvent):
        line_collection.colors = "w"

        pos = figure[0, 0].map_screen_to_world(ev)
        if pos is None:
            return

        # get_nearest_graphics() is a helper function
        # sorted the passed array or collection of graphics from nearest to furthest from the passed `pos`
        nearest = fpl.utils.get_nearest_graphics(pos, line_collection)[0]

        nearest.colors = "r"


    # remove clutter
    figure[0, 0].axes.visible = False

    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 1.114 seconds)


.. _sphx_glr_download__gallery_events_lines_mouse_nearest.py:

.. only:: html

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

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

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

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

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

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

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


.. only:: html

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

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