Trapcode Form

Shading Group

The Shading group adds a special shading effect shading to the particle scene. This set of controls creates shading from composition lights set by After Effects (AE) or Trapcode Lux. Form supports up to 128 Spotlights, 128 Point Lights, and unlimited Ambient Lights.

Shading requires an After Effects light or Lux Light in the Timeline. Once you've created that, Form can add special effects shading. These particles are illuminated based on the characteristics of the light. This page will show its examples with AE Lights, but similar effects can be created with our Lux plugin. Learn about Trapcode Lux here:

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Shading pop-up: By default, the Shading group is turned off with the Shading popup set to the Off option. You switch on the Shading group by setting the Shading popup to On. The Shading group needs to work with composition lights. If there are no lights in your Timeline, when you first turn on the Shading group, the particles will seem disappear.

Here is a good way to test the Shading: Add two Point or Spot Lights. Rotate one Light towards the particles and one away from the particles. Keep at least one light a white color. This is a great way to see how the Shading section works. A helpful Light layer property to adjust is Intensity.



At left, Shading is off. At right, Shading is on. This comp uses three AE Spot lights, one AE Ambient light, and one Trapcode Lux light.

Light Falloff pop-up: The Light's layer property sets its Light Intensity. Light Falloff is what makes that Light Intensity fall away so that the particles far away from the light are less affected by the Shading. Basically, Falloff controls how Light Intensity varies with the distance from the surface to the light. Light Falloff is supported for Spot and Point Lights.


  • Natural (Lux): The default setting. Natural lets the light intensity fall off with distance squared, so that particles further away from the light source will appear darker. This is how natural light intensities fall off in the real physical world. This is also how the Trapcode Lux plug-in behaves in its Natural setting. This setting is the most natural looking, since light sources will affect closer particles more than distant ones.
  • None (AE): All particles get the same amount of shading regardless of the particle’s distance from the light. This is useful in certain situations; for example, if other 3D layers in the comp are also lit by the same lights. After Effects uses a shading model where Point Lights do not fall off, doesn't use distance squared for its 3D layers. You can switch the option to None to be compatible.

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Left to right, Light Falloff set to Natural (Lux) and None (AE).

Using Light properties in AE or Lux: All of the AE Light layer properties are read and used by the Shading group. There are different types of Lights (Point, Spot, Parallel, Ambient) and and each kind has a different set of properties. This includes Color, Intensity, Cone Angle, Light Angle, Orientation and Rotation. These adjustments are all made in the Timeline in the Light properties, not in Particular's interface. However, Particular benefits from those adjustments by displaying their effects.

The Shading controls can also tie directly into the properties set by the Trapcode Lux plug-in. Learn about Lux at



Left to right, Timeline layer properties for an Ambient Light and Point Light. 

Nominal Distance: Defines the distance, measured in pixels, at which the Light has its original Intensity and where the Light Falloff begins. Active when Light Falloff> Natural (Lux) is selected.

For example, if a Light has Intensity at 100% and Nominal Distance is set to 250, this means at a distance of 250 pixels, the Light Intensity will be 100%. Further away there will be a lower Intensity, and closer there will be a higher Intensity.

Ambient: Defines how much ambient light the particles will reflect. Ambient puts the light color in the shadows, where there is no light from the Point Lights or Spot Lights. Ambient light is a background light that is everywhere and radiates in every direction. It is useful for giving some light (color) to particles that are not lit by Spot Lights and Point Lights.

NOTE: Ambient needs to work with an Ambient Light in the Timeline. Remember to create at least one Ambient Light in the comp when using this setting. Default value is 20. High values make the light brighter against the shadow. Low values make the light duller.

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At left, an AE Ambient Light in comp with Ambient at 30. At right, an AE Ambient Light in comp with Ambient at 70.

Diffuse: Defines how much the particles reflect in a diffuse manner. This means the particles reflect in every direction, no matter which direction you are viewing the particle from. This does not tie into any particular Light type, but instead affects all Lights in the composition.

Default value is 80. High values make the light brighter. Low values make the light duller. Matte surfaces typically have a large diffuse component. 

Specular Amount: Simulates a metallic or glossy look for the particles. Active when a Sprite or Textured Polygon particle type is chosen.

Specular defines how much the particles reflect in a more directional way. For example, a glossy surface like plastic or metal have a specular component.

High values make it more glossy. Low values make it less glossy. You may need to lower the Diffuse value to allow the glimmer to come through. Specular Amount is very sensitive to the angle of the particle. 

Specular Sharpness: Defines how narrow the specular reflection is. Active when a Sprite or Textured Polygon particle type is chosen.

For example, glass may be very narrow and plastic slightly less narrow. Sharpness also lets you lower the sensitivity of Specular Amount so it's not so sensitive to the angle of the particle. High values make it more sensitive. Low values make it less sensitive.

Reflection Map: Mirrors the environment in the particle volume. Active when a Sprite or Textured Polygon particle type is chosen.

To create the Map, select a layer in the Timeline that is turned off. This is a great effect for a scene that has to reflect the environment a lot in the particles. If you can create an environment map from the scene, then the particles will blend in really nicely.

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At left, the Reflection Map popup. At right, the Timeline layers it is looking at.

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Left to right, the comp without a Map, the layer used as Map, and the comp with Map applied. 

Reflection Strength: Defines how strong the Reflection Map is. Active when a Sprite or Textured Polygon particle type is chosen.

Since the Reflection Map can be combined with the regular shading from comp Lights, the Reflection Strength is useful for adjusting the look. At the default value of 100, Strength is turned off. Lower values take down the strength of the Reflection Map and mix in the Shading from the scene.

Shadowlet Settings group: Shadowlet Settings provides a soft, self-shadowing for the particle volume. Go to Shadowlet group.