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+.. _doc_real_time_navigation_3d:
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+
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+Real Time Navigation (3D)
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+=========================
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+
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+Introduction
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+------------
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+
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+Pathfinding in a 3D environment is crucial for many games, it's commonly
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+how non directly controlled characters or entities find their way around
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+an environment. Godot provides several nodes for this purpose:
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+
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+- :ref:`NavigationRegion3D<class_NavigationRegion3D>`
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+- :ref:`NavigationAgent3D<class_NavigationAgent3D>`
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+- :ref:`NavigationObstacle3D<class_NavigationObstacle3D>`
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+
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+The map and navigation regions
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+------------------------------
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+
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+The "map" is the entire world for navigation, it's similar to "space" for
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+the physics engine. It's comprised of navigation regions, these regions
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+define what parts of the world that can be navigated around by navigation
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+agents.
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+
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+To create a navigation region add the `NavigationRegion3D<class_NavigationRegion3D>`
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+node to a 3D scene. Next in the inspector for that region create or add a
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+:ref:`NavigationMesh<class_NavigationMesh>`. The navmesh contains options
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+for how it will be generated when it's baked. The geometry options control
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+which nodes, and types of nodes, are used to bake the mesh. A full
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+description of each setting and how it works can be found in the :ref:`NavigationMesh class reference<class_NavigationMesh>`.
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+
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+Once the settings have been properly configured press the "Bake NavMesh"
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+button at the top of the inspector to generate it.
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+
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+.. image:: img/bake_navmesh.png
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+
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+.. note::
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+
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+ It can also be generated at runtime using the `bake_navigation_region()`
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+ method of the navigation region node.
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+
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+Once the mesh has finished generating you should see the transparent
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+navigation mesh above the areas in the scene that can be navigated to.
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+
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+.. image:: img/baked_navmesh.png
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+
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+Keep in mind that the navmesh shows where the center of an entity can
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+go. For example, if you set the agent radius to 0.5 then the
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+navigation mesh will have a distance of 0.5 from any ledges or walls
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+to prevent clipping into the wall or hanging off of the edge.
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+
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+Navigation agents can moved from one region to another if they are next
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+to each other. Additionally A baked navmesh can be moved at runtime and
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+agents will still be able to navigate onto it from another region.
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+For example, navigating onto a moving platform that has stopped will work.
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+
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+NavigationAgent3D
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+-----------------
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+
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+Navigation agent nodes are what actually does the pathfinding in a scene,
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+one can be attached to the root node of an entity that needs to navigate.
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+
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+To have it pathfind use its `set_target_location` method. Once the target
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+has been set a path will be generated to the node using navigation regions,
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+with several points on the way to the final destination.
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+
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+RVO processing
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+--------------
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+
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+RVO stands for reciprocal velocity obstacle. RVO processing is a way to
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+pathfind while taking into account other agents and physics bodies that
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+are also moving.
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+
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+To use it set a target like normal. Then an agent needs to fetch its next
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+nav path location, and compute its velocity to that location. Instead
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+of using that value to move use it to set the velocity on the agent
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+with `set_velocity`. Then a new velocity that takes into account other
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+agents and obstacles is generated and emitted with the signal `velocity_computed`.
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+
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+However agents can only take into account a set number of other nearby
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+agents, this is the :ref:`max neighbors<class_NavigationAgent3D_property_max_neighbors>`
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+property of an agent and can be adjusted. This is **not** a limit for
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+how many agents can use a navigation region at the same time.
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+
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+NavigationObstacle3D
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+--------------------
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+
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+This node is used to mark physics bodies that move around a navigation area
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+that agents need to avoid (this will only work if you use RVO processing).
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+For example, this node would be useful for pieces of debris in a destructible
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+environment. Add it as the child of a physics body and navigation agent
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+nodes will avoid it while pathfinding.
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skyace65
