Glass

Attenuation Density

This is the density of the material. A uniform density is assumed. If this value is greater than 0, the opacity falloff is calculated based on this density and the square of the distance the ray travels inside a refractive material. The larger this value, the higher the density of the material and the more opaque it will appear. Attenuation is only applied when the surface normal and the refracted ray point in opposing directions.

Attenuation Color

This color tints the attenuated opacity.

Specular

Specular Intensity	A multiplier for the specular contribution to the material.
Specular Color	The specular highlight color.
Specular U Roughness	This value controls the size or spread of the specular highlight. If Anisotropic is selected, this value controls the specular highlight in only the U direction.
Specular V Roughness	If Anisotropic is selected, this value controls the specular highlight in only the V direction. It is ignored with any other specular function.
Specular Sharpness	This value controls the sharpness of the edge of the specular highlight. It is used only if Glossy specular is selected.
Specular Type	A selector for the specular function. Glossy is typically used to get the sharp highlight common to glassy surfaces. See specular for more information.

Ray Trace

Index of Refraction

This value is the ratio of the speed of light in one medium, such as air, to that of another medium. This determines how much the ray bends as it passes from one material into another. Higher values tend to "push" the reflections towards the edges. The refractions are in the center.

The expected value is Eta, which is 1/the index of refraction.

Reflections

Reflection Intensity	A multiplier to dim or brighten the reflections.
Reflection Tint	This is a tint color for reflections.
Jitter Amount	This is a value between 0, no jitter and 1, maximum jitter. It controls how randomly the samples are distributed.
Ray Bias	This is typically a small number used to help solve self-intersection issues.
Cone Angle	This is size of the cone (in degrees) over which samples are distributed. Any number greater than zero, will blur the refractions.
Area Samples	The number samples to calculate. The more samples, the better the quality, the slower the render.

Refractions

Refraction Intensity	This is a multiplier to dim or brighten the refractions.
Refraction Tint	This is a tint color for the refractions. This is color is also known as the transmission color. Use this to color the glass or water. A little color goes a long way, so something very pale (desaturated) might be be best to start.
Jitter Amount	This is a value between 0, no jitter and 1, maximum jitter. It controls how randomly the samples are distributed.
Ray Bias	This is typically a small number used to help solve self-intersection issues.
Cone Angle	This is size of the cone (in degrees) over which samples are distributed. Any number greater than zero, will blur the refractions.
Area Samples	The number samples to calculate. The more samples, the better the quality, the slower the render.

Environment Map

Environment Map	If there is the path to a texture here and ray trace is turned off, then this map is used to calculate the reflection contribution. If ray trace is on and there is a texture, then the texture color is returned, when the ray does not hit anything. Without a texture here, the Background Color is returned when the ray misses. It is recommended to have a texture path in this slot. The background image as a texture is a good choice to start.
Transform Space	The reflection ray used to do the look up in the map is transformed into this space. See envmap for more information.
Background Color	This color is returned when the ray does not hit anything and there is no environment map specified.

Lighting Effects

Shadows

Shadow Color

This value is used to tint the color of the shadow cast by the glass.

Caustics

Do Faux Caustics

If the box is checked, a slight trick is played on the shadow value to give a caustic effect.

If using PBR, turn this off, as PBR will automatically generate correct caustics.

Minimum Shadow Intensity

This value is the minimum value of the shadow when Faux Caustics are turned on. These values should be changed to suit the thickness of the object and the implied transparency of the material.

Maximum Shadow Intensity

This value is the maximum value of the shadow when Faux Caustics are turned on. These values should be changed to suit the thickness of the object and the implied transparency of the material.

Decal

Use Decal	When toggled, a decal will be composited over the glass material.
Diffuse Intensity	A multiplier for the diffuse contribution to the decal. This material uses the Oren-Nayer diffuse calculation. This is a more sophisticated diffuse calculation than Lambert s.
Ambient Intensity	A multiplier for the diffuse contribution to the decal. This material uses the Oren-Nayer diffuse calculation. This is a more sophisticated diffuse calculation than Lambert s.
Decal Texture	This the name of the texture file. The icon to the right opens a file browser. Decals must have an alpha channel to work as expected.
Diffuse Roughness	This is an exponent for Oren-Nayer diffuse. It controls the size or spread of the diffuse contribution.

Transformations

Decal X Offset	Translates the UVs in X.
Decal Y Offset	Translates the UVs in Y.
Decal X Scale	Scales the UVs in X.
Decal Y Scale	Scales the UVs in X.
Decal Rotation	Rotates the UVs around Z.

Specularity

Specular Intensity	A multiplier for the specular contribution to the decal.
Specular Color	The specular highlight color, defaults to white.
U Roughness	This value controls the size or spread of the specular highlight. Unless Anisotropic is selected, this value controls the specular highlight only in the U direction.
V Roughness	When Anisotropic is selected, this value controls the specular highlight only in the V direction It is ignored with any other specular function.
Sharpness	When Anisotropic is selected, this value controls the specular highlight only in the V direction It is ignored with any other specular function.
Specular Type	A selector for the specular function. Anisotropic is used to get an elliptical highlight. Glossy is typically used for highly reflective materials to get a sharp edges highlight.
Use Specular Map	A selector for the specular function. Anisotropic is used to get an elliptical highlight. Glossy is typically used for highly reflective materials to get a sharp edges highlight.
Specular Map	This the name of the texture file. The icon to the right opens a file browser.
Spec Map Filter	This the name of the texture file. The icon to the right opens a file browser.
Spec Map Width	This the name of the texture file. The icon to the right opens a file browser.

Properties

Reflect Limit	This limits the number of bounces for a reflection ray. Larger numbers equal longer rendering time and may not improve the images. See render properties for more information.
Refract Limit	This limits the number of bounces for a reflection ray. Larger numbers equal longer rendering time and may not improve the images. See render properties for more information.

Glass material

Parameters