= Varying the fur density by painting attributes =

NOTE:
    This tutorial is a detailed look into what goes on at the network level. An automatic way to create the same effect is to use the [Paint Fur Density|/shelf/paintfurdensity] tool on the shelf.

Varying the fur density will allow you to determine which areas have dense clumps of fur as well as areas that have relatively thin coverage. 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 uses colored fur for better visualization in the viewport.
    
# Set the __Density__ parameter on the [Icon:SOP/fur][Fur SOP|Node:sop/fur] that you created in [Basic fur setup|basicsetup] to `1`.
    
    This will leave you with very few guide hairs.
    
# Insert an [Icon:SOP/attribute][AttribCreate|Node:sop/attribcreate] node before the [Icon:COMMON/null] `SKIN_OUT` node.
    
# Change the __Name__ parameter to `furdensity` and increase the __Value__ parameter to `10` in the [parameter editor|/ref/panes/parms] of the [AttribCreate|Node:sop/attribcreate] node.

    This will leave you with a thicker patch of hair.
    
# Insert a [Icon:SOP/paint][Paint|Node:sop/paint] node between the new [AttribCreate|Node:sop/attribcreate] node and the [Icon:COMMON/null] `SKIN_OUT` node.

    You can do this by selecting the connecting wire, pressing ((Tab)), and typing `paint`. The [Paint SOP|Node:sop/paint] allows you to paint attributes.
    
# Turn on the __Override Color__ parameter and change `Cd` to `furdensity`.
    
# In the scene, click and drag your mouse over the grid to paint it. 

    Brushing with ((MMB)) will make fur less dense, and ((LMB)) will make fur thicker. 
    
    For more information, see the [brush tools|/basics/brush] help.

    NOTE:
        You can change the __Radius__ of your brush by holding ((Shift + LMB)) and dragging or by changing the value in the Operation Controls toolbar. You can also alter the __Opacity__ to make each stroke less intense.
        
# Click ((RMB)) in the viewport and choose __Smooth__ to change the ((MMB)) function to blend between the black and white areas.

    [Image:/images/fur/density_nodes.png]
    
    This screen capture displays the two new nodes you must create for this tutorial.
    
# Change the __Value__ of the `furdensity` [AttribCreate|Node:sop/attribcreate] node from `10` to `200`.

# Turn on the display flag in the [Icon:SOP/fur][Fur SOP|Node:sop/fur] to see the varying amounts of fur.

    [Image:/images/fur/density_fur.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 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]. 

You can also [control the fur density using a texture map|furdensitymap].