Shading group> Shadowlet group

New to Particular 2.0 is the Shadowlet Setting group. This set of controls provides a soft, self-shadowing for the particle volume. Shadowlets create a shadow off the main light. You can imagine it as a projected shadow—a volumetric, cone-shaded simulation of the shadow from each particle as created from the light's perspective.

Why a Shadowlet? Let's say your composition has a lot of particles. Realistically, the center of that particle cluster would be obscured by all of the particles around them. You will want the clustered mass in the center to not be so brightly reflected. The Shadowlet takes care of this issue, and adds to the believability of the scene.

How it works. If you move a composition Light across the Comp Window, you'll see that the shadow it creates reacts to the Shadowlet input. If you rotate the comp to look from behind or at another angle, you'll see the Shadowlet stays in its central location but its shading shifts with the angle.

The full Shadowlet settings subgroup.

Options Panel> Shadowlet Name

Shadowlet is created by calculating the light with names that you specify in the Options panel. When a comp Light has the same name as the Light Name set in the Options Shadowlet area, that Light will be used to control the location of the Shadowlet's shadow.

Enter a Light Name in the Shadowlet field, and use that same name for the Light layer in your Timeline. This will make the Particular recognize the Light layer as a Shadowlet light.

By default, this Light Name is named 'Shadow' and that is often an easy way to organize the lights you create in your composition. But the Light Name can be changed to any other text so you can organize and control the Shadowlet feature the way you prefer. You can find more info on the Options Panel page.

At left, the Shadowlet Name field in Options Panel. At right, the Light layer uses the same name in the Timeline.

Shadowlet for Main

This menu enables self-shadowing for particles in the main system. By default the menu is set to Off. Turn it On to get the appearance of particle's casting shadows. This happens as Particular recognizes the 'Shadow' light.

The Shadowlet for Main options lets you turn the Shadowlet calculation on and off.

At left, Shadowlet for Main is turned Off. At right, Shadowlet is turned On.

Shadowlet for Aux

This control enables self-shadowing for particles in the Aux System. This is an extra, auxiliary particle system that lets the main particles emit their own particles. This option lets you control the shadowing for the main particles separate from the aux particles.

The Shadowlet for Aux options lets you turn the Shadowlet calculation on and off for just the Aux particles.

Color

Color controls the color of the Shadowlet's shadow. Darker colors are most appropriate for the shadow color such as black or dark brown. Pick a color that corresponds to the darker parts of the scene. If you have a colored background layer or if the scene has a tint, the default gray color of the shading generally may make the particles look out of place. Color lets you choose a color that makes the Shadowlet shading blend into the background of the scene.

Left to right, the Shadowlet Color is set to black (the default) and a brighter blue.

Color Strength

The Color Strength controls how strong the RGB is weighted in against the particle color when computing the Shadowlet shadow. Strength sets how the shadowlet Color is blended with the original color of the particle. Set to 100 by default this gives the shadow color full contribution to particles in the shadows area. Lower values will make the shadow color appear to blend less with the particles color.

Some particles do not have a defined color, such as Sprite and Textured Polygon. In such cases, Color Strength should always be at 100. All other particles types, like Sprite Colorize/Fill and Textured Polygon Colorize/Fill have a well-defined color.

Left to right, Color Strength is high and low. Color is set to blue.

Opacity

This control sets the opacity of the Shadowlet shadow, which controls how strong the shading is. Default value is 5. Opacity should typically have a low setting, between 1 and 15 when using Sprite or Textured Polygon particle types otherwise the particles in shadow may appear black.

You can increase the value to crank up the opacity of the shading. In some cases higher values can work, for example, if particles are very spread apart. But in many cases, particles will be fairly densely packed and in these cases a low value should be used so the shadow does not appear too dark.

Adjust Size

The Adjust Size value sets the overall coverage of the Shadowlet area. The default value is 100. High values give greater coverage, while lower values create a smaller shadow volume.

Left to right, Adjust Size is set to low and high values.

Adjust Distance

The Adjust Distance value is the distance in pixels the Shadowlet volume appears from the Shadow Light. This control is set to 100 by default. Lower values place the Shadowlet closer to the Light and therefore the shadow appears darker. Higher values move the Shadowlet farther away from the light source and the shadowlet effect becomes less noticeable.

It is useful to set Distance to 0 initially if you have multiple Lights and you don't know which one to set as the main shadow-casting light.

Left to right, Adjust Distance control set to a low and high value.

Placement

Placement controls where the Shadowlet is positioned in 3D space relative to the particles.

- The Placement menu is set to Auto by default. Auto lets Particular decide the best position setting relative to the particles and shadow casting lights.
- The Project option positions the Shadowlet at a depth that depends on the 'Shadow' Light position.
- The Always Behind option renders the Shadowlet shadow behind the particles in the scene. This setting is useful if the Auto setting causes noticeable flickering.
- Always in Front positions the Shadowlet in front of the particle. This setting is also useful if the Auto setting causes unwanted flickering. Since the shadow is always in front, it can give a greater sense of depth to the particles.

The Placement menu options in the Shadowlet settings subgroup