.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "_gallery/feature_demo/custom_object1.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

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

        :ref:`Go to the end <sphx_glr_download__gallery_feature_demo_custom_object1.py>`
        to download the full example code.

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

.. _sphx_glr__gallery_feature_demo_custom_object1.py:


Minimal Custom Object
=====================

Example that implements a minimal custom object and renders it.

This example simply draws a triangle at the bottomleft of the screen.
It ignores the object's transform and camera, and it does not make use
of geometry or material properties.

It demonstrates:

* How you can define a new WorldObject and Material.
* How to define a shader for it.

.. GENERATED FROM PYTHON SOURCE LINES 17-106



.. image-sg:: /_gallery/feature_demo/images/sphx_glr_custom_object1_001.webp
   :alt: custom object1
   :srcset: /_gallery/feature_demo/images/sphx_glr_custom_object1_001.webp
   :class: sphx-glr-single-img





.. code-block:: Python



    import wgpu
    from rendercanvas.auto import RenderCanvas, loop
    import pygfx as gfx
    from pygfx.renderers.wgpu import (
        Binding,
        BaseShader,
        register_wgpu_render_function,
    )


    # Custom object, material, and matching render function


    class Triangle(gfx.WorldObject):
        pass


    class TriangleMaterial(gfx.Material):
        pass


    @register_wgpu_render_function(Triangle, TriangleMaterial)
    class TriangleShader(BaseShader):
        # Mark as render-shader (as opposed to compute-shader)
        type = "render"

        def get_bindings(self, wobject, shared, scene):
            # Our only binding is a uniform buffer
            bindings = {
                0: Binding("u_stdinfo", "buffer/uniform", shared.uniform_buffer),
            }
            self.define_bindings(0, bindings)
            return {
                0: bindings,
            }

        def get_pipeline_info(self, wobject, shared):
            # We draw triangles, no culling
            return {
                "primitive_topology": wgpu.PrimitiveTopology.triangle_list,
                "cull_mode": wgpu.CullMode.none,
            }

        def get_render_info(self, wobject, shared):
            # Since we draw only one triangle we need just 3 vertices.
            # Our triangle is opaque (render mask 1).
            return {
                "indices": (3, 1),
            }

        def get_code(self):
            # Here we put together the full (templated) shader code
            return """
            {$ include 'pygfx.std.wgsl' $}

            @vertex
            fn vs_main(@builtin(vertex_index) index: u32) -> @builtin(position) vec4<f32> {
                var positions = array<vec2<f32>, 3>(
                    vec2<f32>(10.0, 10.0), vec2<f32>(90.0, 10.0), vec2<f32>(10.0, 90.0)
                );
                let p = 2.0 * positions[index] / u_stdinfo.logical_size - 1.0;
                return vec4<f32>(p, 0.0, 1.0);
            }

            @fragment
            fn fs_main() -> FragmentOutput {
                var out: FragmentOutput;
                out.color = vec4<f32>(1.0, 0.7, 0.2, 1.0);
                return out;
            }
            """


    # Setup scene

    renderer = gfx.WgpuRenderer(RenderCanvas())
    camera = gfx.NDCCamera()  # This material does not actually use the camera

    t = Triangle(None, TriangleMaterial())

    scene = gfx.Scene()
    scene.add(t)


    if __name__ == "__main__":
        renderer.request_draw(lambda: renderer.render(scene, camera))
        loop.run()


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

   **Total running time of the script:** (0 minutes 0.162 seconds)


.. _sphx_glr_download__gallery_feature_demo_custom_object1.py:

.. only:: html

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

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

      :download:`Download Jupyter notebook: custom_object1.ipynb <custom_object1.ipynb>`

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

      :download:`Download Python source code: custom_object1.py <custom_object1.py>`

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

      :download:`Download zipped: custom_object1.zip <custom_object1.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#custom_object1.py"></iframe>