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

.. only:: html

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

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

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

.. _sphx_glr_gallery_scene_magnify.py:


Zoom in using MagnifyCamera
===========================

Demonstrates use of special Camera subclasses to implement a (flashy) 
data-exploration tool.

Here we use MagnifyCamera to allow the user to zoom in on a particular 
region of data, while also keeping the entire data set visible for reference.

The MagnifyCamera classes are responsible for inserting MagnifyTransform
at the transform of each viewbox scene, while also updating those transforms
to respond to user input.

.. GENERATED FROM PYTHON SOURCE LINES 20-103



.. image-sg:: /gallery/scene/images/sphx_glr_magnify_001.png
   :alt: magnify
   :srcset: /gallery/scene/images/sphx_glr_magnify_001.png
   :class: sphx-glr-single-img





.. code-block:: Python


    import numpy as np
    import vispy.scene
    from vispy.scene import visuals
    from vispy.scene.cameras import MagnifyCamera, Magnify1DCamera
    from vispy.visuals.transforms import STTransform
    from vispy.util import filter 

    # 
    # Make a canvas and partition it into 3 viewboxes.
    #
    canvas = vispy.scene.SceneCanvas(keys='interactive', show=True)
    canvas._send_hover_events = True  # temporary workaround
    grid = canvas.central_widget.add_grid()

    vb1 = grid.add_view(row=0, col=0, col_span=2)
    vb2 = grid.add_view(row=1, col=0)
    vb3 = grid.add_view(row=1, col=1)

    #
    # Top viewbox: Show a plot line containing fine structure with a 1D 
    # magnification transform.
    #


    pos = np.empty((100000, 2))
    pos[:, 0] = np.arange(100000)
    pos[:, 1] = np.random.normal(size=100000, loc=50, scale=10)
    pos[:, 1] = filter.gaussian_filter(pos[:, 1], 20)
    pos[:, 1] += np.random.normal(size=100000, loc=0, scale=2)
    pos[:, 1][pos[:, 1] > 55] += 100
    pos[:, 1] = filter.gaussian_filter(pos[:, 1], 2)
    line = visuals.Line(pos, color='white', parent=vb1.scene)
    line.transform = STTransform(translate=(0, 0, -0.1))

    grid1 = visuals.GridLines(parent=vb1.scene)

    vb1.camera = Magnify1DCamera(mag=4, size_factor=0.6, radius_ratio=0.6)
    vb1.camera.rect = 0, 30, 100000, 100

    #
    # Bottom-left viewbox: Image with circular magnification lens.
    #
    size = (100, 100)

    img_data = np.random.normal(size=size+(3,), loc=58, scale=20).astype(np.ubyte)
    image = visuals.Image(img_data, parent=vb2.scene, method='impostor')
    vb2.camera = MagnifyCamera(mag=3, size_factor=0.3, radius_ratio=0.6)
    vb2.camera.rect = (-10, -10, size[0]+20, size[1]+20) 

    #
    # Bottom-right viewbox: Scatter plot with many clusters of varying scale.
    #


    centers = np.random.normal(size=(50, 2))
    pos = np.random.normal(size=(100000, 2), scale=0.2)
    indexes = np.random.normal(size=100000, loc=centers.shape[0]/2., 
                               scale=centers.shape[0]/3.)
    indexes = np.clip(indexes, 0, centers.shape[0]-1).astype(int)
    scales = 10**(np.linspace(-2, 0.5, centers.shape[0]))[indexes][:, np.newaxis]
    pos *= scales
    pos += centers[indexes]

    scatter = visuals.Markers()
    scatter.set_data(pos, edge_color=None, face_color=(1, 1, 1, 0.3), size=5)
    vb3.add(scatter)

    grid2 = visuals.GridLines(parent=vb3.scene)
    vb3.camera = MagnifyCamera(mag=3, size_factor=0.3, radius_ratio=0.9)
    vb3.camera.rect = (-5, -5, 10, 10)

    # Add helpful text
    text1 = visuals.Text("mouse wheel = magnify", pos=(100, 15), font_size=14, 
                         color='white', parent=canvas.scene)
    text2 = visuals.Text("right button = zoom", pos=(100, 30), font_size=14, 
                         color='white', parent=canvas.scene)


    if __name__ == '__main__':
        import sys
        if sys.flags.interactive != 1:
            vispy.app.run()


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

   **Total running time of the script:** (0 minutes 4.355 seconds)


.. _sphx_glr_download_gallery_scene_magnify.py:

.. only:: html

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

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

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

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

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

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

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


.. only:: html

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

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