Specular Configuration Guide

This section covers NiloToon's various specular features, including Hair Specular, Kajiya-Kay Specular, PBR Specular, Metallic Materials, and Stocking Materials.

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Hair/Toon Style Specular

For hair materials, using Specular Method = Toon will provide better toon specular results, since it is easier to control the specular area/shape artistically.

Then adjust the following 3 parameters until the specular looks good for hair.

Setup Example

1. Assign a Specular Mask first - this limits where the specular can appear
2. Set Area Remap Strength to 1
3. Adjust MidPoint appropriately (e.g., 0.5)
4. Set Softness to 0.05

If You Want PBR Specular

For realistic specular like a PBR shader, use Specular Method = GGX PBR and adjust Smoothness instead of using Style Remap.

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Kajiya-Kay Specular (Hair)

This is a very rarely used feature, designed for producing a dynamic hair "Angel Ring".

To produce better specular, Position Offset needs to be manually adjusted for each hair material.

Usage Limitations

This feature requires all UV islands in UV0 (first UV set/channel) to be lined up vertically (all hair root vertices at the top of the UV, and tips at the bottom of the UV). Most models' UV0 do not have this special format, so this feature is generally not recommended.

Only when UV0 is set up this way will the auto-generated tangent using UV0 produce the correct data for this feature to calculate accurate hair specular.

Using with Regular UV Models

If your model only has regular UV, you can provide an additional UV to use this feature.

UV Channel	Purpose
UV0	Vertically aligned special UV
UV1	Regular UV for BaseMap color

With this data setup, the auto-generated tangent using UV0 will work correctly, and you can sample the BaseMap color using UV1.

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Specular & Smoothness

The following groups are typically used together:

• Smoothness/Roughness (Specular)
• Specular Highlights

Main Uses

• Realistic cloth/plastic/metal PBR reflection
• Realistic skin reflection (sweat/oil/water effects) - used for swimsuit outfits, sexy models, etc.

Complementary Maps

Specular results will be greatly improved by using the following PBR maps together:

Map Type	Purpose
Normal Map / Detail Map (Normal)	Surface detail
Smoothness / Roughness Map	Reflection intensity
Occlusion Map	Ambient occlusion
Metallic Map	Metallic property

Packed Texture Support

Packing Smoothness, Occlusion, and Metallic into a single texture is common practice. NiloToon can read a target channel from a texture, so you can use these PBR packed maps directly.

MatCap (Add/Specular/RimLight) is also frequently used together. While not PBR or realistic, it provides stable specular from a matcap texture that does not depend on light direction or color.

GGX PBR vs Toon Specular

In the Specular Highlights group, the default Specular Method is PBR GGX. It uses the PBR specular algorithm, and you primarily control the specular shape using the Smoothness/Roughness slider.

Smoothness Adjustment Examples

Smoothness Value	Result
0.3
0.5
0.7

When Specular Method = Toon, it uses the classic NPR specular algorithm, and Smoothness is ignored. You control the specular shape manually using the Style Remap sliders. This is well suited for setting up hair specular with a Reflection Shape Mask.

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Specular Intensity in Shadow

Control specularInShadowMinIntensity in NiloToonCharRenderingControlVolume.

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Metal/Reflect/Rim/Specular Material

You can use the following features within the character material to create metallic materials.

(1) MatCap (Alpha Blend)

Typically generated by AI tools (e.g., Nano Banana 2).

(2) Environment Reflection

Displays the scene's Reflection Probe data. This feature requires you to bake Reflection Probes in the scene.

(3) MatCap (Additive)

Ideal for adding rim light or highlights using a matcap texture.

(4) Specular Highlights

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Black Stocking Material

To produce the black stocking effect, use BaseMap Stacking Layer.

Before applying BaseMap Stacking Layer

After applying BaseMap Stacking Layer

Setup Method

Configure the BaseMap Stacking Layer as follows:

Setting	Value
Blending Mode	Multiply RGB
Mask UV Mode	MatCapUV
Mask Texture	Select Matcap_ShadowSoft
Layer Content Color	A dark color (e.g., black or deep gray)

This allows you to tint a surface only at grazing angles. Adjust the Mask's Remap (0 to 1) to fine-tune the shape of the black stocking effect.

Adding Specular Reflection

Once the edge tint effect is complete, add specular reflection, which is another important element of the black stocking effect. See the Specular & Smoothness section above.