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

.. only:: html

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

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

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

.. _sphx_glr__gallery_validation_validate_line_loop.py:


Line loop
=========

Drawing multiple line loops using material.loop and separating line-pieces with nans.

.. GENERATED FROM PYTHON SOURCE LINES 7-132



.. image-sg:: /_gallery/validation/images/sphx_glr_validate_line_loop_001.webp
   :alt: validate line loop
   :srcset: /_gallery/validation/images/sphx_glr_validate_line_loop_001.webp
   :class: sphx-glr-single-img





.. code-block:: Python




    import numpy as np
    from rendercanvas.auto import RenderCanvas, loop
    import pygfx as gfx


    canvas = RenderCanvas(size=(1000, 800))
    renderer = gfx.WgpuRenderer(canvas)
    scene = gfx.Scene()

    # This example ensures there are no visual artifacts with transparent lines
    # for closed loops. Add a background to help demonstrate that.
    scene.add(gfx.Background.from_color("#fff", "#000"))


    def circle(n, x=0, y=0):
        t = np.linspace(0, 2 * np.pi, n, endpoint=False)
        return np.stack([x + np.sin(t), y + np.cos(t), np.zeros_like(t)], axis=1)


    nanpoint = np.full((1, 3), np.nan, dtype="f4")
    rect_points = np.array([[-1, -1, 0], [-1, +1, 0], [+1, +1, 0], [+1, -1, 0]], "f4")

    # This line-piece has all straight corners. It covers the fix for a
    # bug wherer 90 degree corner, aligned with the coordinate frame,
    # resulted in a glitch in the line join.
    all_corners = np.array(
        [
            [0, 0, 0],
            [0, 1, 0],
            [1, 1, 0],
            [1, 0, 0],
            [0.8, 0, 0],
            [0.8, 0.8, 0],
            [0.2, 0.8, 0],
            [0.2, 0.2, 0],
            [0.4, 0.2, 0],
            [0.4, 0.6, 0],
            [0.6, 0.6, 0],
            [0.6, 0, 0],
        ],
        "f4",
    )
    all_corners *= 5
    all_corners += (-8, 3, 0)


    positions = np.vstack(
        [
            # Special case
            all_corners,
            nanpoint,
            # Increasingly more corners
            circle(0, -7, 0),  # actuall zero points, so two successive nanpoints
            nanpoint,
            circle(1, -4, 0),
            nanpoint,
            circle(2, -1, 0),
            nanpoint,
            circle(3, +2, 0),
            nanpoint,
            nanpoint,  # ensure 2 successive nanpoints don't crash the shader
            nanpoint,
            circle(4, +5, 0),
            nanpoint,
            # Even more corners
            circle(5, -7, -3),
            nanpoint,
            nanpoint,  # ensure many successive nanpoints don't crash the shader
            nanpoint,
            nanpoint,
            nanpoint,
            nanpoint,
            circle(6, -4, -3),
            nanpoint,
            circle(7, -1, -3),
            nanpoint,
            circle(8, +2, -3),
            nanpoint,
            circle(9, +5, -3),
            nanpoint,
            # These become circles
            circle(12, -7, -6),
            nanpoint,
            circle(24, -4, -6),
            nanpoint,
            circle(48, -1, -6),
            nanpoint,
            circle(96, +2, -6),
            nanpoint,
            circle(192, +5, -6),
            # nanpoint,  # optional
        ],
        dtype="f4",
    )

    line1 = gfx.Line(
        gfx.Geometry(positions=positions),
        gfx.LineMaterial(
            thickness=14, color="red", alpha_mode="blend", opacity=0.7, loop=True, aa=True
        ),
    )
    scene.add(line1)


    line2 = gfx.Line(
        gfx.Geometry(positions=rect_points * 10),
        gfx.LineMaterial(
            thickness=20, color="cyan", alpha_mode="blend", opacity=0.7, loop=True, aa=True
        ),
    )
    scene.add(line2)

    camera = gfx.OrthographicCamera(500, 500)
    camera.show_object(scene, match_aspect=True, scale=1.1)
    controller = gfx.PanZoomController(camera, register_events=renderer)


    canvas.request_draw(lambda: renderer.render(scene, camera))

    if __name__ == "__main__":
        print(__doc__)
        loop.run()


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

   **Total running time of the script:** (0 minutes 0.668 seconds)


.. _sphx_glr_download__gallery_validation_validate_line_loop.py:

.. only:: html

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

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

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

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

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

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

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


.. only:: html

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

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

.. only:: html

    Interactive example
    -------------------

    Try this example in your browser using Pyodide. Might not work with all examples and all devices. Check the output and your browser's console for details.

    .. raw:: html

        <iframe src="./../pyodide.html#validate_line_loop.py"></iframe>