Rim Lighting
Rim Lighting can be used to add a highlight or glow around the edges (or center) of a material. It uses the angle between your view and the normal of the surface to define the intensity of the effect.
Rim Lighting is sometimes referred to in conjunction with or as Fresnel, in reference to the Fresnel Effect.
Demonstration of 3 different Rim Lighting effects with low sharpness (left), high sharpness (middle), and colored rim lighting (right).
Style
Type: Dropdown, Options:Poiyomi/UTS2/LilToon
Choose the style of Rim Lighting that you wish to use.
Poiyomi
Uses the in-house Rim style made exclusively for Poiyomi Shaders.
UTS2
Uses the Rim style that is known in Unity-Chan Toon Shader 2.
LilToon
Uses the Rim style that is well known in LilToon Shader.
Mask & Bias
Type: Data Texture (sRGB: OFF)
A texture overlaid on the mesh defining the intensity of the rim lighting at each point. It should generally be black and white, as only its value (specifically the red channel value) will be used, not the color.
When expanded, the Rim Mask texture has options for Tiling and Offset. The assigned UV Map and the Panning of the Rim Mask can be adjusted.
Bias Intensity
Bias of the Mask Intensity.
Color & Blending
Demonstration of the Rim Lighting Color & Blending options.
Rim Texture
Type: Color Texture (sRGB: ON)
A texture overlaid on the mesh defining the color of the rim lighting.
When expanded, the Rim Texture has options for Tiling and Offset. The assigned UV Map and the Panning of the Rim Texture can be adjusted.
Color
Type: Color
The Color of your Rim Lighting. Blended with the base color.
This color is blended multiplicative with the Rim Texture, if defined.
This will instead be an HDR Color field if using LilToon Rim Lighting mode.
Blend Mode
Type: Dropdown, Options:Add/Replace/Multiply/Mixed/Screen
Choice of how the Rim Lighting will blend with the base texture.
Blend Alpha
Type: Float, Range:0.0 - 1.0
Controls the Alpha visibility of the Rim Lighting. 0 is invisible, while 1 is fully visible.
Mix Base Color
Type: Float, Range:0.0 - 1.0
Controls how much the Rim Lighting's Color will blend with the Base Color.
Brightness
Type: Float, Range:0.0 - 10.0
Controls how bright the Rim Lighting will be overall.
Emission
Type: Float, Range:0.0 - 20.0
Controls the emission value of the rim lighting color. Emission emulates a part of a material that produces light, and adds directly on top of the base color.
Total emission values above 1 will generally cause glow in worlds with bloom.
Shape Controls
Demonstration of the Rim Lighting Shape Controls.
Width
Type: Float, Range:0.0 - 1.0
Controls the width of the rim lighting. Affects how far from the edge (or center) the rim extends.
Sharpness
Type: Float, Range:0.0 - 1.0
Controls the sharpness of the transition between minimum and maximum rim lighting. At 0, the rim will be a gradual transition, with the maximum color only present at the very outer edge. As Rim Sharpness increases, the maximum color extends further toward the edge as defined by the Rim Width. At 1, there is a sharp transition between no rim lighting and rim lighting.
Rim Power
Type: Float, Range:0.0 - 10.0
Controls how intense the Rim Lighting has an effect.
Normal Strength
Type: Float, Range:0.0 - 1.0
Controls how the Rim Lighting will blend with your Normals. A value of 0 ignores your Normals, while a value of 1 will fully blend within your Normals.
Invert Rim
Type: Checkbox
Inverts the Rim Lighting direction. When unchecked, rim lighting goes from "outside-in" (facing away from viewer has maximum intensity). When checked, rim lighting goes from "inside-out" (facing toward viewer has maximum intensity).
Light Direction Mask
Type: Checkbox
Enables the ability to mask the Rim Lighting to a Lighting Direction Mask, whether that would be Custom or to use the Shadow Map.
Light Falloff Type
Type: Dropdown, Options:Shadow Map/Custom
Choice of the Light Falloff Map it's going to use as a Mask.
Invert Shadow Mask
Type: Checkbox
Inverts the values of the Shadow Mask
Shadow Mask Strength
Controls the intensity of that Mask.
Shrink In Shadow
Lowers the size of the Rim Light Width in the Masked area.
Hue Shift
Type:Checkbox
Enables the Hue Shift feature in Rim Lighting.
Color Space
Type: Dropdown, Options:OKLab/HSV
Choice of Color Space to use for the Hue Shift. By default, it will be set to OKLab.
Learn about the difference of Color Spaces as documented here in Color Adjust.
Shift Speed
Type: Float
Sets the speed at which the rim color's hue value is shifted. At a value of 1, it will go through a complete cycle of the color wheel once every 20 seconds.
Hue Shift
Type: Float, Range:0.0 - 1.0
A fixed value by which to hue shift the material. At values of 0 and 1, there will be no change to the material. In between, the hue will shift through the color wheel.
Alpha & Global Masking
Apply to Alpha
Type: Dropdown, Options:Off/Add/Multiply
Choice to apply the Rim Lighting to the Material Alpha.
Apply to Alpha Blend
Type: Float, Range:0.0 - 1.0
Controls how much to Apply the Rim to your Alpha.
Global Mask
Type: Dropdown, Options:Off/1R/1G/1B/1A/2R/2G/2B/2A/3R/3G/3B/3A/4R/4G/4B/4A
Choose to use a Global Mask to constrain the Rim Lighting to the specified Mask instead. Overrides Mask & Bias.
Apply to Global Mask
Type: Dropdown, Options:Off/1R/1G/1B/1A/2R/2G/2B/2A/3R/3G/3B/3A/4R/4G/4B/4A
Allows you to add the currently set Rim Lighting setup to be applied to an existing Global Mask of your choice.
AudioLink
The settings in this section will only be visible when AudioLink is activated on the Material.
Demonstration of the AudioLink Controls on the Bass Band for Rim Lighting.
Width Add Band
Type: Dropdown, Options:Bass/Low Mid/High Mid/Treble/Volume
Which Band to use for the Width.
Width Add
Type: Vector2
How much to add to or subtract from the Rim Lighting Width with Audio.
| Modifier | Function |
|---|---|
| Min | Amount changed to Rim Width with No Audio in Width Add Band |
| Max | Amount changed to Rim Width with Max Audio in Width Add Band |
Emission Add Band
Type: Dropdown, Options:Bass/Low Mid/High Mid/Treble/Volume
Which Band to use for the Rim Emission.
Emission Add
Type: Vector2
How much to add to or subtract from the Rim Lighting Emission with Audio.
| Modifier | Function |
|---|---|
| Min | Amount changed to Rim Emission with No Audio in Emission Add Band |
| Max | Amount changed to Rim Emission with Max Audio in Emission Add Band |
Brightness Band
Type: Dropdown, Options:Bass/Low Mid/High Mid/Treble/Volume
Which Band to use for the Rim Brightness.
Brightness Add
Type: Vector2
How much to add to or subtract from the Rim Lighting Brightness with Audio.
| Modifier | Function |
|---|---|
| Min | Amount changed to Rim Brightness with No Audio in Brightness Band |
| Max | Amount changed to Rim Brightness with Max Audio in Brightness Band |