---
title: "PxrRodLightFilter"
canonical: "https://rmanwiki-25.pixar.com/space/REN25/20415690/PxrRodLightFilter"
format: markdown
---
PxrRodLightFilter uses a "rod" like object to block light. The rod can be shaped into an irregular shape. This rod is then placed next to the object where we want to block the light.

This light filter is a more extensive version of <u>[PxrBlockerLightFilter](https://renderman.atlassian.net/wiki/spaces/REN25/pages/20416378)</u>.


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### Parameters


#### Rod Shape

**Width**

Width of the inner region of the rod (X axis).

**Height**

Height of the inner region of the rod (Y axis).

**Depth**

Depth of the inner region of the rod (Z axis).

**Radius**

Radius of the corners of the inner rod box.

**Edge**

Thickness of the edge region.

#### Scale

**Scale Width**

Scale the width of the inner rod shape (X axis).

**Scale Height**

Scale the height of the inner rod shape (Y axis).

**Scale Depth**

Scale the depth of the inner rod shape (Z axis).

#### Refine Shape

**Left**

Additional size of the left region (-X axis)

**Right**

Additional size of the right region (+X axis)

**Bottom**

Additional size of the bottom region (-Y axis)

**Top**

Additional size of the top region (+Y axis)

**Back**

Additional size of the back region (-Z axis)

**Front**

Additional size of the front region (+Z axis)

#### Scale Edges

**Left Edge**

Scale left edge up or down (-X axis).

**Right Edge**

Scale right edge up or down (+X axis).

**Bottom Edge**

Scale bottom edge up or down (-Y axis).

**Top Edge**

Scale top edge up or down (+Y axis).

**Back Edge**

Scale back edge up or down (-Z axis)

**Front Edge**

Scale frontal edge up or down (+Z axis).

#### Multiplier

Multiplies various aspects of intensity in the filter.

**Density**

Global control on how much effect this light filter has.

**Intensity**

Multiplier for the light intensity.

**Invert**

Invert the multipliers.

**Diffuse Contribution**

Controls the diffuse contribution.

**Specular Contribution**

Controls the specular contribution.

**Saturation**

Saturation of the light before hitting the surface (0=greyscale, 1=normal,>1=boosted colors).


#### Falloff

Controls the transition from the core to the edge:


**Falloff**

Define the number of knots. This is a float ramp that controls the transition from the core to the edge.

![Rod_Falloffout0.jpg](media://9fd87d1c-d428-4868-9709-4f63828e8666)

**Falloff Knots**

An array of knot values.


**Falloff Floats**

An array of float values.


**Falloff Interpolation**

Type of ramp interpolation:

- linear
- catmull-rom
- bspline
- constant


Optional color gradient for the transition:


**Color Ramp**

Define the number of knots.

![Rod_ColorRamp.jpg](media://1836add6-bf93-4a2c-bfd0-865866ced9ca)

**Color Ramp Knots**

An array of knot values.


**Ramp Colors**

An array of color values.


**Color Ramp Interpolation**

Type of color ramp interpolation:

- linear
- catmull-rom
- bspline
- constant


#### Combine Mode

Combine Mode

**mult**: The results of all the filters are multiplied together

**max**: The maximum result from all filters is used.This works best for grey scale light filters.

**min**: The minimum result from all filters is used.This works best for grey scale light filters.

**screen**: Similar to the max operation, but it combines gradients in a smoother way. This works best for grey scale light.

Light filters on a light are grouped by their combine mode. Light filters in the same group are executed together and combined by the combine mode.The groups are executed in this order (max, min, screen, and then mult) and are multiplied together, which means a filter that turns things black in the mult group will zero out all other filters.