.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "gallery/scene/instanced_mesh_picking.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_instanced_mesh_picking.py>`
        to download the full example code.

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

.. _sphx_glr_gallery_scene_instanced_mesh_picking.py:


Picking Instance of InstancedMeshes
===================================

Demonstrates how to identify (pick) individual instanced meshes.

.. GENERATED FROM PYTHON SOURCE LINES 14-97



.. image-sg:: /gallery/scene/images/sphx_glr_instanced_mesh_picking_001.png
   :alt: instanced mesh picking
   :srcset: /gallery/scene/images/sphx_glr_instanced_mesh_picking_001.png
   :class: sphx-glr-single-img





.. code-block:: Python


    import numpy as np

    from vispy import app, scene, use
    from vispy.io import read_mesh, load_data_file
    from vispy.scene.visuals import InstancedMesh
    from vispy.scene import transforms
    from scipy.spatial.transform import Rotation

    #Necessary to use InstancedMesh
    use(gl='gl+')

    canvas = scene.SceneCanvas(keys='interactive', bgcolor='white')
    view = canvas.central_widget.add_view()

    view.camera = 'turntable'
    view.camera.depth_value = 1e3

    #Load an mesh file
    mesh_path = load_data_file('spot/spot.obj.gz')

    n_instances = 8
    vertices, faces, normals, texcoords = read_mesh(mesh_path)
    instance_colors = np.random.rand(n_instances, 3).astype(np.float32)
    instance_positions = [[0,2,0], [2,0,0], [6,0,0], [3,4,1], [5,3,2], [6,2,1], [8,4,6], [1,2,6]]
    instance_transforms = Rotation.identity(n_instances).as_matrix().astype(np.float32)

    # Create a colored `MeshVisual`.
    mesh = InstancedMesh(
        vertices,
        faces,
        instance_colors=instance_colors,
        instance_positions=instance_positions,
        instance_transforms=instance_transforms,
        parent=view.scene,
    )

    scene.visuals.XYZAxis(parent=view.scene)
    mesh.interactive = True

    @canvas.events.mouse_press.connect
    def on_mouse_press(event):
        clicked_mesh = canvas.visual_at(event.pos)
        if isinstance(clicked_mesh, InstancedMesh):
            pos1, min, min_pos = get_view_axis_in_scene_coordinates(
                event.pos, clicked_mesh
            )
            instance_pos = clicked_mesh.instance_positions[min_pos]
            print(f"visual at : {clicked_mesh}")
            print(f"event.pos : {event.pos}")
            print(f"min distance : {min} and min_pos : {instance_pos}")
       


    def get_view_axis_in_scene_coordinates(pos, mesh):
        event_pos = np.array([pos[0], pos[1], 0, 1])  
        instances_on_canvas = []
        # Translate each position to corresponding 2d canvas coordinates
        for instance in mesh.instance_positions:
            on_canvas = mesh.get_transform(map_from="visual", map_to="canvas").map(instance)
            on_canvas /= on_canvas[3:]
            instances_on_canvas.append(on_canvas)

        min = 10000
        min_pos = None
        # Find the closest position to the clicked position
        for i, instance_pos in enumerate(instances_on_canvas):
            # Not minding z axis
            temp_min = np.linalg.norm(
                np.array(event_pos[:2]) - np.array(instance_pos[:2])
            )
            if temp_min < min:
                min = temp_min
                min_pos = i

        return instances_on_canvas, min, min_pos

    canvas.show()


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


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

   **Total running time of the script:** (0 minutes 0.937 seconds)


.. _sphx_glr_download_gallery_scene_instanced_mesh_picking.py:

.. only:: html

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

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

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

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

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

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

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


.. only:: html

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

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