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

    Click :ref:`here <sphx_glr_download_gallery_mplot3d_voxels_rgb.py>` to download the full example code
.. rst-class:: sphx-glr-example-title

.. _sphx_glr_gallery_mplot3d_voxels_rgb.py:


==========================================
3D voxel / volumetric plot with rgb colors
==========================================

Demonstrates using ``ax.voxels`` to visualize parts of a color space




.. image:: /gallery/mplot3d/images/sphx_glr_voxels_rgb_001.png
    :class: sphx-glr-single-img





.. code-block:: python


    import matplotlib.pyplot as plt
    import numpy as np

    # This import registers the 3D projection, but is otherwise unused.
    from mpl_toolkits.mplot3d import Axes3D  # noqa: F401 unused import


    def midpoints(x):
        sl = ()
        for i in range(x.ndim):
            x = (x[sl + np.index_exp[:-1]] + x[sl + np.index_exp[1:]]) / 2.0
            sl += np.index_exp[:]
        return x

    # prepare some coordinates, and attach rgb values to each
    r, g, b = np.indices((17, 17, 17)) / 16.0
    rc = midpoints(r)
    gc = midpoints(g)
    bc = midpoints(b)

    # define a sphere about [0.5, 0.5, 0.5]
    sphere = (rc - 0.5)**2 + (gc - 0.5)**2 + (bc - 0.5)**2 < 0.5**2

    # combine the color components
    colors = np.zeros(sphere.shape + (3,))
    colors[..., 0] = rc
    colors[..., 1] = gc
    colors[..., 2] = bc

    # and plot everything
    fig = plt.figure()
    ax = fig.gca(projection='3d')
    ax.voxels(r, g, b, sphere,
              facecolors=colors,
              edgecolors=np.clip(2*colors - 0.5, 0, 1),  # brighter
              linewidth=0.5)
    ax.set(xlabel='r', ylabel='g', zlabel='b')

    plt.show()


.. _sphx_glr_download_gallery_mplot3d_voxels_rgb.py:


.. only :: html

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



  .. container:: sphx-glr-download

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



  .. container:: sphx-glr-download

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


.. only:: html

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

    Keywords: matplotlib code example, codex, python plot, pyplot
    `Gallery generated by Sphinx-Gallery
    <https://sphinx-gallery.readthedocs.io>`_
