= Casting shadows =



Casting shadows on the fur makes it appear more natural and rich-looking. However, there are certain parameters on the lights you may need to customize when casting shadows from fur. This tutorial is a continuation of [Basic fur setup|basicsetup] and [Using guide hairs|usingguides].

NOTE:
    The fur in the screen captures has color that was created in [Changing the color of the fur using the color attribute|changingcolor].
    
    You can do this tutorial without completing the [Using guide hairs|usingguides] and [Changing the color of the fur using the color attribute|changingcolor] tutorials. This example simply uses red fur for better visualization and contrast in the render.
    
# Click the [Icon:OBJ/light_spot][Spot Light|/shelf/lightsandcameras] tool on the shelf, then click in the [scene view|/ref/views/3dview] to place it.

    For more information on placing lights, see the [Icon:OBJ/light][Lights and Cameras|/shelf/lightsandcameras] help.
    
# On the __Shadow__ tab of the [Spot Light|Node:OBJ/light] node, set the __Shadow Type__ to __Depth Map Shadows__.

    Rendering with Ray-Traced Shadows will significantly slow down render time. It much better to use Depth Map Shadows when rendering fur.

# Make sure the __Auto-generate Shadow Map__ parameter is turned on. It should already be on by default.
    
# Place another [Icon:SOP/grid][Grid|Node:sop/grid] object in your scene by clicking it on the shelf, then clicking in the [scene view|/ref/views/3dview] to place it. 

    You should try to place it in the same spot as the grid you created in [Basic fur setup|basicsetup]. This step is for visualization purposes, and is specific to this tutorial. Normally, any shadows would be cast on the skin geometry of your character. 
    
# Scale the new grid object slightly larger than your patch of fur. This will provide a base for the shadows to be cast on.

# In order to see the shadows, you must [render|/rendering] your image.

[Image:/images/fur/shadow_after.png]

Remember, the [Fur SOP|Node:sop/fur] should only be used for visualization in the viewport. In order to render, it is highly recommended that you use a [Fur Procedural|/nodes/shop/vm_geo_fur], which will delay the generation of fur until render time. For more information on setting this up, see [Basic Fur Setup|basicsetup].  

== Tips ==

* You may want to increase the __Pixel Samples__ to `3` on the __Depth Map Options__ sub-tab of the __Shadow__ tab on your [Spot Light|Node:OBJ/light]. This will improve the quality of the shadows.

* You can also increase the __Resolution__. However, increasing the __Pixel Samples__ and __Resolution__ will increase render time.
    
    For example, try a __Resolution__ of `512` for previewing and `2000` for rendering. Also, try setting your __Pixel Samples__ to `3x3` for the shadow maps (__Depth Map Options__ sub-tab of the __Shadow__ tab on the light) and `8x8` in mantra (__Render__ sub-tab of the __Properties__ tab).
    
* If you do not see any shadows being generated, try increasing the __Value__ of the individual hairs on the `width` attribute and decreasing the __Density__ of the fur on the [Fur Procedural|/nodes/shop/vm_geo_fur].

* Rendering with shadows naturally slows down render time. If you are simply doing test renders you may want to render without shadows.

Remember, the [Fur SOP|Node:sop/fur] should only be used for visualization in the viewport. In order to render, it is highly recommended that you use a [fur procedural shader|/nodes/shop/vm_geo_fur], which will delay the generation of fur until render time. For more information on setting this up, see [Basic fur setup|basicsetup].