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Light Path Node
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.. figure:: /images/render_cycles_nodes_input_light-path.png
   :align: right

   Light Path Node.

The *Light Path* node is used to find out for which kind of incoming ray the shader is being executed;
particularly useful for non-physically based tricks. More information about the meaning of each type
is in the :doc:`Light Paths </render/cycles/settings/light_paths>` documentation.


Inputs
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This node has no inputs.


Properties
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This node has no properties.


Outputs
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Is Camera Ray
   1.0 if shading is executed for a camera ray, 0.0 otherwise.
Is Shadow Ray
   1.0 if shading is executed for a shadow ray, 0.0 otherwise.
Is Diffuse Ray
   1.0 if shading is executed for a diffuse ray, 0.0 otherwise.
Is Glossy Ray
   1.0 if shading is executed for a glossy ray, 0.0 otherwise.
Is Singular Ray
   1.0 if shading is executed for a singular ray, 0.0 otherwise.
Is Reflection Ray
   1.0 if shading is executed for a reflection ray, 0.0 otherwise.
Is Transmission Ray
   1.0 if shading is executed for a transmission ray, 0.0 otherwise.
Ray Length
   Distance traveled by the light ray from the last bounce or camera.
Ray Depth
   Number of times the ray has "bounced", i.e. been reflected or transmitted on interaction with a surface.

   .. note::

      Passing through a transparent shader
      :ref:`does not count as a normal "bounce" <render-cycles-light-paths-transparency>`.

Transparent Depth
   Returns the number of transparent surfaces passed through.
Transmission Depth
   Replace a Transmission lightpath after X bounces with another shader, e.g a Diffuse one.
   This can be used to avoid black surfaces, due to low amount of max bounces.