.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "gallery/3Dvispy/16-multi_volume_sources.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

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

        :ref:`Go to the end <sphx_glr_download_gallery_3Dvispy_16-multi_volume_sources.py>`
        to download the full example code.

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

.. _sphx_glr_gallery_3Dvispy_16-multi_volume_sources.py:


Use different volume sources for different slice directions
===========================================================

``create_slices`` accepts an axis source dictionary. This is useful for large
volumes when the best storage layout differs by slice direction, for example a
binary memmap for inline slices and zarr/lazy arrays for crossline and time
slices. Each source must expose the same logical 3D shape. If a source is
stored in another physical axis order, wrap it as
``{'data': source, 'axes': ('z', 'y', 'x')}``.

The demo keeps the data self-contained by wrapping one memmap with two lazy
sources. The wrappers make the y and z slices visibly different, and they only
transform the slice that is requested. In a real project, replace any value in
``axis_sources`` with another numpy-like source, such as a zarr array. The z
source below uses a transposed view only to demonstrate the axis-order API; in
practice this can be a separate on-disk source stored as ``(nt, nx, ni)``.


.. image:: ../../_static/cigvis/3Dvispy/16.png
    :alt: image
    :align: center

.. GENERATED FROM PYTHON SOURCE LINES 29-84

.. code-block:: Python


    # sphinx_gallery_thumbnail_path = '_static/cigvis/3Dvispy/16.png'


    import numpy as np
    import cigvis
    from pathlib import Path


    root = Path(__file__).resolve().parent.parent.parent

    sxp = root / 'data/rgt/sx.dat'
    ni, nx, nt = 128, 128, 128
    shape = (ni, nx, nt)


    class LazyTransformedVolume:
        def __init__(self, source, transform):
            self.source = source
            self.transform = transform
            self.shape = source.shape
            self.ndim = source.ndim

        def __getitem__(self, key):
            return self.transform(np.asarray(self.source[key], dtype=np.float32))


    seismic = np.memmap(sxp, np.float32, 'r', shape=shape)
    seismic_zyx = np.transpose(seismic, (2, 1, 0))

    axis_sources = {
        # Inline slices use the original seismic memmap.
        'x': seismic,
        # Crossline slices use a second source with reversed polarity.
        'y': LazyTransformedVolume(seismic, lambda x: -x),
        # Time/depth slices use a source declared as physical (z, y, x).
        'z': {
            'data': LazyTransformedVolume(seismic_zyx, np.abs),
            'axes': ('z', 'y', 'x'),
        },
    }

    nodes = cigvis.create_slices(
        axis_sources,
        pos={'x': [36], 'y': [28], 'z': [84]},
        cmap='Petrel',
        clim=[-4, 4],
    )
    nodes += cigvis.create_colorbar_from_nodes(nodes, 'Amplitude', select='slices')

    cigvis.plot3D(
        nodes,
        view=cigvis.Plot3DView(size=(750, 600)),
        save=cigvis.Plot3DSave(path='example.png', transparent_bg=False),
    )


.. _sphx_glr_download_gallery_3Dvispy_16-multi_volume_sources.py:

.. only:: html

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

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

      :download:`Download Jupyter notebook: 16-multi_volume_sources.ipynb <16-multi_volume_sources.ipynb>`

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

      :download:`Download Python source code: 16-multi_volume_sources.py <16-multi_volume_sources.py>`

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

      :download:`Download zipped: 16-multi_volume_sources.zip <16-multi_volume_sources.zip>`


.. only:: html

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

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