Glossy Material


The GlossyThe measure of how well light is reflected from a surface in the specular direction, the amount and way in which the light is spread around the specular direction, and the change in specular reflection as the specular angle changes. Used for shiny materials such as plastics or metals. material creates shiny materials such as plastics or metals. You can edit the parameters for the Glossy materialUsed for shiny materials such as plastics or metals. when you select the MaterialThe representation of the surface or volume properties of an object. node (figure 1).


Figure 1: Glossy material parameters


Glossy Material Parameters

DiffuseAmount of diffusion, or the reflection of light photons at different angles from an uneven or granular surface. Used for dull, non-reflecting materials or mesh emitters. - Gives color to the material. In computer graphics, this is also referred to as base color or albedo. You can set Diffuse color by using the color picker, or by connecting a Texture (Procedural or Image).

SpecularAmount of specular reflection, or the mirror-like reflection of light photons at the same angle. Used for transparent materials such as glass and water. - Determines the intensity of specular reflections that appear on the surface. Specular reflections are reflections of light sources on the surface. The Specular input accepts color values and textures. In most cases, specular highlights are white or colorless. To simulate metallic surfaces, the Specular color should use a color similar to the Diffuse parameter. Think of the bright yellow-orange highlights seen on the surface of a polished copper kettle.

BRDF Model- The BRDF (Bidirectional Reflectance Distribution Function) determines the amount of light that a material reflects when light falls on it. For Glossy materials, you can choose from six BRDF models. Specific geometric properties (the micro-facet distribution) of the surface affects each BRDF, which describes the surface's microscopic shape (i.e. micro-facet normals) and scales the brightness of the BRDF's reflections. Refer to the topic on BRDF Models in the Standalone documentation for more information.


Roughness - Determines how much the specular reflection spreads across the surface. In CG terminology, this is also known as reflection blur. A value of 0 simulates a perfect smooth reflective surface, such as a mirror. Increasing the value simulates microfacets in the surface, which causes the reflective highlights to spread. For example, to create the look of worn plastic, increase the Roughness value. This parameter accepts a value or Texture map (Procedural or Image).

Anisotropy - Adjusts the amount of change that a surface's reflectance has, depending on viewing direction.

Rotation - Controls the Anisotropy effect's orientation.

Spread - The spread of the tail when using the STD BSDF model.

Film Width - Simulates the look of a thin film of material on the surface. This is useful when you want to create an effect like the rainbow colors that appear on an oil slick surface. Larger values increase the effect's strength.

Film IOR - The Film IOR controls the thin film's Index of Refraction. Use this option to adjust the film's visible colors.

Sheen - Provides control for applying a soft luster to a surface.

Sheen Roughness - This parameter determines how the sheen spreads across the surface. Lower values create a sharp and narrow effect, while higher values spread the effect across a larger surface area.

Index Of Refraction - Determines the strength of surface reflections based on the Fresnel law. The Fresnel law describes the physical properties of light as it is reflected off of a surface at grazing angles. If Index of Refraction is set to a value higher than 1, the reflection is strongest on the part of the surface that turns away from the viewer’s angle (grazing angles), while the reflection appears weaker or less apparent on the parts of the surface perpendicular to the viewing angle. Since this is a physical phenomena, the result is a more realistic-looking surface. If Index of Refraction is set to a value lower than 1, then the Fresnel effect is disabled and the reflection color appears as a uniform color across the highlight. The color of the reflective highlight itself is determined by the color connected to the Specular channel.

Allow Caustics - If enabled, the photon tracing kernel will create caustics for light reflecting or transmitting through the object.

Opacity - Determines what parts of the surface are visible in the render. Dark values indicate transparent areas, and light values determine opaque areas. Values in-between light and dark create the look of semi-transparent areas. You can lower the Opacity value to fade the overall visibility of an object, or use a Texture map to vary the opacity across the surface. For example, if you want to make a simple polygon plane look like a leaf, you connect a black-and-white image of the leaf’s silhouette to the Diffuse shader's Opacity channel.

Bump - Creates fine details on the material’s surface using a Procedural or Image texture. When you connect a Greyscale texture to this parameter, light areas of the texture look like protruding bumps, and dark areas look like indentations. You can adjust the strength by adjusting the Power or GammaThe function or attribute used to code or decode luminance for common displays. The computer graphics industry has set a standard gamma setting of 2.2 making it the most common default for 3D modelling and rendering applications. values on the Image texture node. These attributes are covered in more detail under the MediumsThe behavior of light inside a surface volume described by scatter, absorption, and transmission characteristics. category.

Normal - This also creates the look of fine detail on the surface. A Normal map is a special type of image texture that uses red, green, and blue color values to perturb the normals of the surface at render time, thus giving the appearance of added detail. They can be more accurate than Bump maps, but require specific software, such as ZBrush®, Mudbox®, Substance Designer, Xnormal, or others to generate.

DisplacementThe process of utilizing a 2D texture map to generate 3D surface relief. As opposed to bump and normal mapping, Displacement mapping does not only provide the illusion of depth but it effectively displaces the actual geometric position of points over the textured surface. - Adjusts the height of a surface's vertices at render time using a Texture map. Displacement maps differs from Bump or Normal maps in that the geometry is altered by the texture, as opposed to creating the appearance of detail. Displacement mapping is more complex than using a Bump or Normal map, but the results are more realistic, in particular along the surface's silhouette. Displacement mapping is covered in more detail under the Mediums category.

Smooth - Smooths the transition between surface normals. If this option is disabled, the edges between the polygons of the surface are sharp, giving the surface a faceted look.

Smooth Shadow Terminator - If enabled, self-intersecting shadows are smoothed according to the polygon's curvature.

Round Edges - Smooth sharp edges during render time.


Priority - Used to resolve the ambiguity in overlapping surfaces, the surface priority control allows artists to control the order of preference for surfaces. A higher number suggests a higher priority for the surface material, which means it is preferred over a lower priority surface material if a ray enters a higher priority surface and then intersects a lower priority surface while inside the higher priority surface medium.

Custom AOV - Writes a mask to the specified custom AOV.

Custom AOV Channel - Determines whether the custom AOV is written to a specific color channel (R, G, or B) or to all the color channels.

Material Layer - This input accepts any Material Layer types as an additional layer of material design.