Corona Toon Material

The Toon material changes how the Diffuse and Reflectivity (especially specular highlights) respond to lighting. Instead of following realistic shading, they use color gradients defined by ramps in the material settings. When a strong light source is used—like the Corona Sun—these gradients don’t blend smoothly, but instead create a banded or posterized look, with clear, sharp transitions between different brightness levels.

Toon material is very useful for avoiding becoming locked in to specific materials, letting the focus remain on the building, design, interior layout, etc. This can be handy early in a project, but sometimes can also be useful for final deliverables, too, where a photorealistic render may present a very specific material that will not be the one used in the actual construction giving confusing expectations. Toon material can also be used purely for artistic purposes as well, for conveying a particular feel or mood.

General

Diffuse color – Specifies the diffuse color. The Diffuse Ramp value is multiplied by the Diffuse color value.

Roughness – Controls the smoothness of the base layer of the surface. A value of 0 (or black, if a map is used) results in a completely smooth surface, which leads to sharp reflections or refractions of the base layer. A value of 1 (or white, if a map is used) results in a completely rough surface leading to blurred reflections (or refractions).

Ambient color – Specifies an ambient color affecting only direct rays and not the GI.

IOR – Sets the Index of Refractions for a non-metal (dielectric) object, which controls how much a ray is bent when entering the object, and the amount of reflection in a physically plausible way. A value of 1 results in no bending of the ray and no reflection, while the value of 1.52 is good for generic glass. 

Diffuse Ramp

Number – Specifies the number of the currently selected gradient ramp key.

Color – Specifies the color of the key. 

Position – Specifies the position of the currently selected key on the gradient ramp within a range from 0 to 1.

Interpolation – Determines the type of the transition effect between the selected gradient ramp key and the other keys. See the Diffuse Ramp Interpolation example below.

Ramp Offset – Shifts the ramp input, as if the ramp keys are moved left. See the Diffuse Ramp Offset example below.

Output Offset – Shifts the ramp output, as if the ramp keys are brighter colors. 

Specular Ramp

Number – Specifies the number of the currently selected gradient ramp key.

Color – Specifies the color of the key. 

Position – Specifies the position of the currently selected key on the gradient ramp within a range from 0 to 1.

Interpolation – Determines the type of the transition effect between the selected gradient ramp key and the other keys. See the Specular Ramp Interpolation example below.

Ramp Offset – Shifts the ramp input, as if the ramp keys are moved left. 

Output Offset – Shifts the ramp output, as if the ramp keys are brighter colors. 

Refraction

Amount – Specifies the amount of refraction and the refraction color. Any value above zero (black) enables refraction.

Caustics – Enables physically correct unbiased caustics. When disabled, faster, transparent shadows are used. 

Opacity

Level – Both the constant color and the texture map are multiplied by this value. Setting this parameter to 0.5 or using a white color is equal to using 50% gray color, or using a texture map with output level of 0.5.

Clip – When enabled, Clip applies a threshold to the opacity map, so that everything below 50% gray is completely transparent, and everything above 50% gray is completely opaque. This option can speed up rendering significantly.

Color – Specifies opacity color, where white is opaque, and black is transparent. 

Anisotropy

Value – Specifies the anisotropy of the glossy reflection highlight. A value of 0 disables anisotropy, which creates a perfectly isotropic highlight. A value of -1 creates a maximally anisotropic highlight in one axis, and a value of 1 creates maximally anisotropic highlight in the perpendicular axis.

Simple – This option doesn’t affect the material’s reflection highlights.

Shaped – This option allows picking a custom shape for the material’s reflection highlights. See the Anisotropy example below.

Textured – This option defines the material’s reflection highlight shape based on a custom texture.

Light color replacement

Enable – When enabled, the color for all lights illuminating an object with the material is replaced by the given color. 

Blend type – Specifies how the original light color is blended with the replacement color. 

Over
Add
Subtract
Multiply
Lighten
Darken
Saturate
Desaturate

Color – Specifies the color that replaces the light color. 

Blend intensity – Specifies an amount for blending the original light and the diffuse color. A value of 0 results in no light blending, while a value of 1 results in full light blending. 

Displacement

Min level – Specifies displacement distance applied to areas with black (0.0) texture. This value is measured in world-space units. 

Texture – Specifies a texture map that controls the min/max levels of the displacement. 

Max level – Specifies strength of the displacement effect. The world-space displacement distance is applied to areas with white (1.0) texture. 

Water lvl. – When enabled, specifies a displacement cutoff threshold. Any microtriangle with displacement texture below the Water level is removed. 

Advanced

G-Buffer ID override – If set to a value different than 1, it overrides the 3ds Max GBuffer property. This option allows you to set values outside the permitted 3ds Max range of 0 to 15.

Propagate masks – Specifies the propagation of non-shading render elements (masks) after interaction with the material. Available modes are:

Never – Mask passes are never propagated through the material, i.e. the material is always visible in masks.
Through reflection – Mask passes are propagated through the material if reflection occurs.
Through refraction – Mask passes are propagated through the material if refraction occurs.
Always – Mask passes are always propagated through the material, i.e. the material is never visible in masks.
Invisible in masks – This mode makes the material invisible in masks.

The Maps rollout provides further control over the following parameters: Diffuse color, Roughness, IOR, Refraction amount, Anisotropy, Opacity color, Displacement. Each of these can be controlled through a texture map.