The alphaCutoff property can be used to specify the cutoff value when using the Mask alphaMode. Alpha values below the threshold will be rendered fully transparent, everything else will be fully opaque. The default value is 0.5

See also alphaMode.

This property sets the mode for how the alpha channel of material color is used.

Note: These modes only consider the alpha channel of the material's color or color map. The general opacity of the material does therefore not affect how the alphaMode or alphaCutoff is interpreted.

This property sets the base color for the material. Depending on the type of material specified (metal or dielectric) the diffuse and specular channels will be set appropriately. For example, a dielectric material will have a diffuse color equal to the base color, while it's specular color, depending on the specular amount, will have a bright specular color. For metals the diffuse and specular channels will be mixed from the base color and have a dark diffuse channel and a specular channel close to the base color.

This property defines the texture used to set the base color of the material.

See also baseColor.

This property determines how the colors of the model rendered blends with those behind it.

This property determines the color of self-illumination for this material. If an emissive map is set, this property is used as a factor for the RGB channels of the texture.

Note: In a scene with black ambient lighting a material with a emissive factor of 0 will appear black wherever the light does not shine on it; turning the emissive factor to 1 will cause the material to appear as its diffuse color instead.

Note: When you want a material to not be affected by lighting, instead of using 100% emissiveFactor consider setting the lightingMode to PrincipledMaterial.NoLighting for a performance benefit.

This property sets a Texture to be used to set the emissive factor for different parts of the material. Using a grayscale image will not affect the color of the result, while using a color image will produce glowing regions with the color affected by the emissive map.

This property controls how fast light travels through the material.

This property defines which lighting method is used when generating this material.

The default value is PrincipledMaterial.FragmentLighting

When using PrincipledMaterial.FragmentLighting, diffuse and specular lighting is calculated for each rendered pixel. Certain effects (such as a Fresnel or normal map) require PrincipledMaterial.FragmentLighting to work.

When using PrincipledMaterial.NoLighting no lighting is calculated. This mode is (predictably) very fast, and is quite effective when image maps are used that you do not need to be shaded by lighting.

The metalness property defines the metalness of the the material. The value is normalized, where 0.0 means the material is a dielectric (non-metallic) material and a value of 1.0 means the material is a metal.

Note: In principle, materials are either dielectrics with a metalness of 0, or metals with a metalness of 1. Metalness values between 0 and 1 are still allowed and will give a material that is a blend between the different models.

This property sets a Texture to be used to set the metalness amount for the different parts of the material.

This property defines an RGB image used to simulate fine geometry displacement across the surface of the material. The RGB channels indicate XYZ normal deviations.

Note: Normal maps will not affect the silhouette of a model.

This property controls the amount of simulated displacement for the normalMap.

This property contains the factor used to modify the values from the occlusionMap texture. The value should be between 0.0 to 1.0. The default is 1.0

This property defines a texture used to determine how much indirect light the different areas of the material should receive. Values are expected to be linear from 0.0 to 1.0, where 0.0 means no indirect lighting and 1.0 means the effect of the indirect lighting is left unchanged.

See also occlusionAmount.

This property drops the opacity of just this material, separate from the model.

This property defines a Texture used to control the opacity differently for different parts of the material.

Note: This must be an image format with transparency for the opacity to be applied.

This property controls the size of the specular highlight generated from lights, and the clarity of reflections in general. Larger values increase the roughness, softening specular highlights and blurring reflections.

This property defines a Texture to control the specular roughness of the material.

This property controls the strength of specularity (highlights and reflections).

Note: For non-dielectrics (metals) this property has no effect.

Note: This property does not affect the specularReflectionMap, but does affect the amount of reflections from a scenes SceneEnvironment::lightProbe.

Note: Unless your mesh is high resolution, you may need to use PrincipledMaterial.FragmentLighting to get good specular highlights from scene lights.

The property defines a RGB Texture to modulate the amount and the color of specularity across the surface of the material. These values are multiplied by the specularAmount.

Note: The specular map will be ignored unless the material is dielectric.

This property sets a Texture used for specular highlights on the material. By default the Texture is applied using environmental mapping (not UV mapping): as you rotate the model the map will appear as though it is reflecting from the environment. Specular Reflection maps are an easy way to add a high-quality look with relatively low cost.

Note: Using a Light Probe in your SceneEnvironment for image-based lighting will automatically use that image as the specular reflection.

Note: Crisp images cause your material to look very glossy; the more you blur your image the softer your material will appear.

This property defines how much of the base color contributes to the specular reflections.

Note: This property does only apply to dielectric materials.