The V-Ray Car Paint Material material is a material that simulates a metallic car paint. It is a complex material with four layers: a base diffuse layer, a base glossy layer, metallic flakes layer, and clear coat layer. The material allows the adjustment of each of these layers separately.

Basic Properties

Name – here you can enter a name for the object.

Layer – If an element was assigned to a layer its layer color will be displayed here. This field reflects the layer color in the Layer Palette. You can drag & drop layers from the Layer Browser or similar layer fields onto this field. You can also assign layers or remove elements from current layers using the menus located behind the small triangle.

Preview Quality – quality of material preview in preview window.

Overridable – when you use Override material options in Global options, you can specify some materials that will no be override, like glasses, curtains etc..it useful for preview vizualization of interiors.

MatID Color – ID of the material for multipass rendering.

Round Edges – edges of object with this material will be rounded.

Base layer

Base color – the diffuse color for the base layer.

Texture Map – here an image texture or shader can be defined.

Bump Map – here an image texture or shader can be defined.

Bump amount – the amount of bump. A value of 0.0 means the object will appear unchanged. Higher values produce a greater bump effect. Intensity of the bump is sets in really world units, thous units are taken from the c4d units of the file, if you change the units there also the bump size changes accordingly. Bump amount value can`t be negative.

Amount Map – here an image texture or shader can be defined.

Bump Type – the type of the bump map

  • Texture output
  • Normal map in tangent space
  • Normal map in object space
  • Normal map in camera space
  • Normal map in world space
  • Texture bump output
  • Explicit normal
Trace Reflections – if this is off, reflections will not traced.

Reflection Amount – controls reflection visibity of Base Layer.

Texture Map – here an image texture or shader can be defined.

Reflection Glossiness – controls the sharpness of reflections. A value of 1.0 means perfect mirror-like reflection; lower values produce blurry or glossy reflections.

Texture Map – here an image texture or shader can be defined.

Flakes layer

Flakes Color – the color of the metal flakes.

Texture Map – here an image texture or shader can be defined.

Flake Glossiness – the glossiness of the metal flakes. It is not recommended to set this above 0.9 as it may produce artifacts.

Texture Map – here an image texture or shader can be defined.

Flakes Orientation – controls the orientation of the flakes relative to the surface normal. When this is 0.0, all flakes are perfectly aligned with the surface. When it is 1.0, the flakes are rotated completely randomly with respect to the normal. Values above 0.5 are not recommended as they can produce artifacts.

Texture Map – here an image texture or shader can be defined.

Flakes Density – the density (number of flakes) for a certain area. Lower values produce less flakes and higher values produce more flakes. Set this to 0.0 to produce a material without flakes.

Flakes Size – scales the entire flake structure.

Map Size – internally the material creates several bitmaps to store the generated flakes. This parameter determines the size of the bitmaps. Lower values reduce RAM usage, but may produce noticeable tiling in the flake structure. Higher values require more RAM, but tiling is reduced.

Random Seed– random value to define placement of flakes on surface.

Flakes Filtering – this is a threshold below which reflections will not be traced. VRAYforC4D tries to estimate the contribution of reflections to the image, and if it is below this threshold, these effects are not computed. Do not set this to 0.0 as it may cause excessively long render times in some cases.

  • Simple – this method is faster and uses less RAM but is less accurate. It averages the orientation of the flakes together, which may alter the appearance of the material when viewed from a distance.
  • Directional – this method is slightly slower and uses more RAM but is more accurate. It groups the flakes based on their orientation before performing the filtering, so that the material appearance is preserved.

Map Type – specifies the method for mapping the flakes. The possible values are:

  • Explicit UVW channel – the flakes are mapped using the specified channel.
  • Triplanar from Object XYZ – the material automatically computes mapping coordinates in object space based on the surface normals.

Trace Reflections – when off, the flakes will only produce specular hilights, but no actual reflections will be traced.

Coat Layer

Coat Color – the color of the coat layer.

Texture Map – here an image texture or shader can be defined.

Coat Strength – the strength of the coat reflections when the surface is viewed directly from the front.

Texture Map – here an image texture or shader can be defined.

Coat Glossiness – glossiness of the coat reflections.

Texture Map – here an image texture or shader can be defined.

Bump Map – here an image texture or shader can be defined.

Bump amount – the amount of bump. A value of 0.0 means the object will appear unchanged. Higher values produce a greater bump effect. Intensity of the bump is sets in really world units, thous units are taken from the c4d units of the file, if you change the units there also the bump size changes accordingly. Bump amount value can`t be negative.

Amount Map – here an image texture or shader can be defined.

Bump Type – the type of the bump map

  • Texture output
  • Normal map in tangent space
  • Normal map in object space
  • Normal map in camera space
  • Normal map in world space
  • Texture bump output
  • Explicit normal
Trace Reflections – if this is off, the clear coat will only produce specular hilights, but no actual reflections.

Options

Trace reflections – when disabled, reflections from the different layers are not traced (they will only produce specular hilights).

Double Sided – when enabled, the material is double-sided.

Subdivisions – determines the amount of samples for the glossy reflections of the different layers.

Cut-Off – cutoff threshold for the reflections of the different layers.

Env Override – specifies the environment priority for the environment override texture for this material.

Texture Map – here an image texture or shader can be defined.

Example: The Flake Orientation

Flake orientation is 0.0

Flake orientation is 0.1

Flake orientation is 0.3

This set of images demonstrate the effect of the Flake orientation parameter. Note how lower values produce flakes more aligned with the surface normal, so that light is reflected more uniformly. Higher values produce more random flakes leading to more variation in the flake illumination.

Example: The Flake Density Parameter

Flake density is 0.5

Flake density is 1.0

Flake density is 2.0

This set of images shows the effect of the Flake density parameter. Note how larger values produce more flakes, but do not change the flake size.

Example: The Flake Scale Parameter

Flake scale is 0.005

Flake scale is 0.01

Flake scale is 0.02

This set of images demonstrate the effect of the Flake scale parameter. Note how lower values scale the entire flake structure.

Example: The Flake Size Parameter

Flake size is 0.5

Flake size is 1.0

Flake size is 2.0

This set of images shows the effect of the Flake size parameter. Note how larger values make the individual flakes larger, but do not change their count.

Example: The Flake Filtering Parameter

No filtering and no antialiasing; the result is very noisy because of the small flake size.

No filtering, Adaptive DMC antialiasing. The result is accurate, but very slow since a lot of AA samples are required to antialias the flakes.

Flake filtering set to Simple, no antialiasing. The filtering greatly reduces the noise, but alters the appearance of the material.

Flake filtering set to Directional, no antialiasing. The noise is reduced and the material appearance is correctly preserved.

This example shows the effect of the Flake filtering parameter.

Example: Antialiasing Filters

Simple filtering
Flake map size
is 256.
Flake maps take less than 1 MB.

Directional filtering
Flake map size is 256.
Flake maps take 10 MB.

Simple filtering
Flake map size is 512.
Flake maps take between
1 and 2 MB
.

Directional filtering
Flake map size is 512.
Flake maps take 40 MB

Simple filtering
Flake map size is 1024.
Flake maps take 5 MB.

Directional filtering
Flake map size is 1024.
Flake maps take 161 MB.

Simple filtering
Flake map size is 2048
Flake maps take 21 MB.

Directional filtering
Flake map size
is 2048.
Flake maps take 645 MB.

Here is an example briefly demonstrating the effect of different antialiasing filters on the final result.

Note that rendering with a particular filter is not the same as rendering without a filter and then blurring the image in a post-processing program like Adobe Photoshop. Filters are applied on a sub-pixel level, over the individual sub-pixel samples. Therefore, applying the filter at render time produces a much more accurate and subtle result than applying it as a post effect.

The Adaptive image sampler was used for the images below, with Min/Max rate of -1/3 and the Rand option on.