Point Light

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This node shades a three-dimensional surface as if it were illuminated by a point light.  The node's input defines this surface as a height map.  More sophisticated lighting can be achieved with Full Light.



Point Lights Make Height Maps Look 3D

Point Lights make height maps look three-dimensional.



Point Light Used To Select Angle

Point Lights are also useful for selecting the areas of a surface that have a certain angle, such as in

this example where a Point Light enables snow to be added only to upward-facing parts of the rock.






This node accepts one input, which it uses as a height map for constructing a three-dimensional surface.  Only the red channel of the input is used by the node.










The small white circle on the surface of the light sphere in the Properties panel specifies the relative location of the light source illuminating the height map.  Change the location of the light by dragging the white circle, or by changing the values within the rotation angle and elevation angle fields below the light sphere.

Height Factor

This property scales all values of the input height map by a given factor to quickly change overall elevations.  Entering a negative value will reverse elevations.

Shadow Strength

Increasing this property darkens any hard shadows cast by the light.  This property will not have any effect if Global Illumination has been set to the maximum value.

Global Illumination

Increasing this value causes more simulated light rays to find their way via indirect means to areas of the surface that do not have direct line-of-sight with the light.  Global Illumination helps to give the surface a more natural appearance.

Ambient Occlusion

This value controls the extent to which indirect light rays form soft shadowing on the surface.

Occlusion Radius

Along with the Ambient Occlusion property, this property also influences any soft shadowing appearing on the surface.  Occlusion Radius will not have any effect if Ambient Occlusion is set to zero.

Skip for Color Only

During color-only renders, certain parts of a texture, usually those adding highlights or shadows, are skipped so that a flat-looking version is created.  Activating this property will cause this node to render as if it had a Height Factor of zero, thus flattening away any highlights.  This property doesn't have an effect during normal renders.  More information on color-only rendering can be found in the Using Effect Maps tutorial.




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