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

    Click :ref:`here <sphx_glr_download_auto_tutorials_05_physics_viz_ball_collide.py>` to download the full example code
.. rst-class:: sphx-glr-example-title

.. _sphx_glr_auto_tutorials_05_physics_viz_ball_collide.py:


=========================
Ball Collision Simulation
=========================

This example simulation shows how to use pybullet to render physics simulations
in fury. In this example we render the collision between a blue ball and red
ball and also display a message by confirming the collision.

First some imports.


.. code-block:: default

    import numpy as np
    from fury import window, actor, ui
    import itertools
    import pybullet as p

    client = p.connect(p.DIRECT)







Parameters and defination of red and blue balls.


.. code-block:: default


    red_radius = 0.5
    blue_radius = 0.5
    duration = 50

    # Red Ball
    red_ball_actor = actor.sphere(centers=np.array([[0, 0, 0]]),
                                  colors=np.array([[1, 0, 0]]),
                                  radii=red_radius)

    red_ball_coll = p.createCollisionShape(p.GEOM_SPHERE, radius=red_radius)

    red_ball = p.createMultiBody(baseMass=0.5,
                                 baseCollisionShapeIndex=red_ball_coll,
                                 basePosition=[10, 0, 0],
                                 baseOrientation=[0, 0, 0, 1])

    # Blue ball
    blue_ball_actor = actor.sphere(centers=np.array([[0, 0, 0]]),
                                   colors=np.array([[0, 0, 1]]),
                                   radii=blue_radius)

    blue_ball_coll = p.createCollisionShape(
        p.GEOM_SPHERE,
        radius=blue_radius)

    blue_ball = p.createMultiBody(baseMass=0.5,
                                  baseCollisionShapeIndex=blue_ball_coll,
                                  basePosition=[-10, 0, 0],
                                  baseOrientation=[0, 0, 0, 1])







We set the coefficient of restitution of both the balls to `0.6`.


.. code-block:: default


    p.changeDynamics(red_ball, -1, restitution=0.6)
    p.changeDynamics(blue_ball, -1, restitution=0.6)







We add all the actors to the scene.


.. code-block:: default


    scene = window.Scene()
    scene.add(actor.axes())
    scene.add(red_ball_actor)
    scene.add(blue_ball_actor)

    showm = window.ShowManager(scene,
                               size=(900, 700), reset_camera=False,
                               order_transparent=True)

    showm.initialize()
    counter = itertools.count()








Method to sync objects.


.. code-block:: default


    def sync_actor(actor, multibody):
        pos, orn = p.getBasePositionAndOrientation(multibody)
        actor.SetPosition(*pos)
        orn_deg = np.degrees(p.getEulerFromQuaternion(orn))
        actor.SetOrientation(*orn_deg)


    apply_force = True
    tb = ui.TextBlock2D(position=(0, 600), font_size=30, color=(1, 0.5, 0),
                        text="")
    scene.add(tb)
    scene.set_camera(position=(0.30, -18.78, 0.89),
                     focal_point=(0.15, 0.25, 0.40),
                     view_up=(0, 0, 1.00))








Timer callback to sync and step simulation every second.


.. code-block:: default


    def timer_callback(_obj, _event):
        global apply_force
        cnt = next(counter)
        showm.render()
        red_pos, red_orn = p.getBasePositionAndOrientation(red_ball)
        blue_pos, blue_orn = p.getBasePositionAndOrientation(blue_ball)

        # Apply force for the first step of the simulation.
        if apply_force:
            p.applyExternalForce(red_ball, -1,
                                 forceObj=[-40000, 0, 0],
                                 posObj=red_pos,
                                 flags=p.WORLD_FRAME)

            p.applyExternalForce(blue_ball, -1,
                                 forceObj=[40000, 0, 0],
                                 posObj=blue_pos,
                                 flags=p.WORLD_FRAME)

            apply_force = 0

        sync_actor(blue_ball_actor, blue_ball)
        sync_actor(red_ball_actor, red_ball)

        # Get various collision information using `p.getContactPoints`.
        contact = p.getContactPoints(red_ball, blue_ball, -1, -1)
        if len(contact) != 0:
            tb.message = "Collision!!"

        p.stepSimulation()

        if cnt == 50:
            showm.exit()


    showm.add_timer_callback(True, duration, timer_callback)

    interactive = False

    if interactive:
        showm.start()

    window.record(scene, size=(900, 700), out_path="viz_ball_collide.png")



.. image:: /auto_tutorials/05_physics/images/sphx_glr_viz_ball_collide_001.png
    :class: sphx-glr-single-img





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

   **Total running time of the script:** ( 0 minutes  0.221 seconds)


.. _sphx_glr_download_auto_tutorials_05_physics_viz_ball_collide.py:


.. only :: html

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



  .. container:: sphx-glr-download

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



  .. container:: sphx-glr-download

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


.. only:: html

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

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