General Truelight Material Settings

Many Truelight materials used in VRED share properties.

Incandescence

The effect of the object itself giving off light. Incandescence is useful in various cases where an object needs to be lit without the use of a full light object in the scene. Settings are available for the object to affect the lighting of only itself or the surrounding scene.

Intensity

The strength of the effect (Range -0-1000).

Color

The color of the light rays.

Use Texture

Enables the use of a texture to control the intensity of the effect according to the texture values.

If this option is selected for multiple texture slots of a material, their texture mapping settings are linked together. When changing, for example, the Repeat UV of a linked texture, it is changed for all linked textures at once. When selecting this option for a texture while other textures of that material already have the link option selected, the texture settings are set to the settings of the already linked textures.

Depending on the type of material, the setting options can vary. For common materials light Plastic and Phong, there are now three mapping types selectable for the using textures:

Mapping Type

Sets the mapping type of the texture. There are three modes which can be selected.

Repeat Mode UV

Sets the repeat mode of the texture. There are four modes:

Repeat

Repeats the texture in all directions.

Mirror

Repeats and mirrors the texture on the x- And y- Axis with every repetition.

Decal

The texture is not repeated.

Clamp

Repeats only the last pixel of the texture.

For UV Mapping Type

Repeat UV

Sets the number of repetitions for the UVs.

Offset UV

Sets the offset for the UVs.

Rotate

Rotates the UVs.

For Planar Mapping Type

Projection Center

Coordinates (x, y, z) of the projection center can be set here.

Projection Orientation

Offers the possibility to incline the projection plane.

Projection Size

Sets the size of the projection. Textures default to infinite projection depth and cover the entire object. You can restrict the texture to one side of the object by limiting the range of the projection. Changing the Z value of the projection size from zero (infinite) to another value achieves the restriction.

Keep Aspect Ratio

If selected, the size corresponding to the original aspect ratio of the texture is automatically adjusted.

Rotate

Sets the projection plane’s rotation on the X/Y/Z- Axis.

Manipulate

Adjusts the texture on the selected object. Hold the Shift key and drag on the manipulator to rotate, scale, or translate the texture. Dragging the blue scale control adjusts the depth limit of the texture.

Fit Size

Adjusts the size of the projection plane to the selected object.

Object Center

Adjusts the projection center to the center of the selected object.

For Triplanar Mapping Type

Texture Size X, Y

Defines the textures size on the X-/Y- Axis.

X Repeat UV, Y/UV, Z/UV

Set the repetition value of the U and V- Axis for each projection direction.

X Offset UV, Y/UV, Z/UV

Set the offset value of the U and V- Axis for each projection direction.

X/Y/Z Rotate

Sets the projection orientation.

Manipulate

Applies the texture to the selected surface.

Anisotropy

Sets the texture filter quality for the image texture. Value 1 is lowest quality. Value 16 is highest quality.

Evaluate Ray Lights (Raytracing Only)

Enables evaluation of ray lights on the surface. This is used to be able to look into a ray file light and to make it visible in reflections and refractions. The origins of the rays should be on the surface to be evaluated.

Use as Light Source (Raytracing Only)

Uses the material as a light source for other materials in the scene while raytracing.

Illuminate Shadow Material

Allows the incandescence light shadow materials. Set the Reflection Mode of the shadow material to Diffuse, Glossy, or Diffuse + Glossy.

Cast Shadow on Shadow Material

Allows other objects to cast shadows on the shadow material due to the material's incandescence illumination.

Shadow Intensity

Sets the intensity of shadows cast by the geometry light.

Importance Multiplier

If Use As Light Source is selected, objects with this material function as geometric light sources. A value higher than one increases the probability that the light source emits photons at the photon mapping. This is useful for dark light sources in an interior if incident light comes from outside Environments.

Interactive/Still Frame Quality

Controls the illumination and sets the light sampling quality during interactive/still frame rendering.

Transparency Settings

Define the shader’s opacity.

See Through

Renders the shader transparent.

Invert Texture

Inverts the texture.

The Texture, Repeat, Offset, Rotate, and Anisotropy settings are described in the General Truelight Material Settings - Incandescence section.

Subsurface Scattering

Subsurface Scattering Video Captions: In VRED 2021, we have now improved the way we are calculating subsurface scattering. The new algorithm is a brute force volume-scattering algorithm. This is very helpful for materials like translucent plastics, marble, skin, or leaves. In the material setting of a plastic, you can enable the volume scattering, and choose between two types. Below, you will find all necessary settings for achieving different subsurface scattering looks. This new feature gives you the possibility to get a more realistic and physically correct look and behavior of your materials. Thanks for watching the video.


Translucency and subsurface scattering are two different methods for calculating light passing through the back of an object into the observer's eye. While translucency requires far less calculation power, subsurface scattering offers more possibilities and greater flexibility.

Subsurface scattering simulates the effect of light entering an object and scattering beneath its surface. Use this for the realistic rendering of materials, such as translucent plastic, marble, skin, leaves, wax, and milk. With these types of materials, not all light reflects from a surface. Some of it will penetrate below the surface of an illuminated object. There, it will be absorbed by the material and scattered internally. Some of this scattered light will make its way back out of the surface and become visible to the camera.

Scattering Mode

There are two modes when operating with translucency, depending on what objects to project:

None

Disables subsurface scattering.

Thin Walled Translucency

Simulates translucency on single-sided objects, so the subsurface is rendered as a translucent object being lit from behind. Use for thin-sided objects, such as bubbles, thin cloth, thin leaves, lamp shades, or sheet of paper lit from behind.

It requires more calculation time than the solid translucency mode, but when in doubt, use this mode.

Volume Scattering

Simulates light scattered by a thin, uniform atmosphere. This produces shafts of light and volumetric shadows cast from geometric objects. Use it for fog or smoke. It works with point, spot, area, rectangular, spherical, disc, and directional lights, but not with ray.

Color

Determines the color of the scattering/translucent light.

Roughness

Defines the amount of diffusion that is applied to translucent light.

Scattering Mode Subsurface Scattering

Incoming light on the averted side of an object is refracted in all directions. With this mode, it is possible to simulate the behavior of wax or other translucent materials. There are two modes available:

Single Scattering

Allows light to bounce once inside a material before it is reflected to the outside. This mode is less accurate but requires less calculation time than multiple scattering.

Multiple Scattering

Allows light to bounce several times inside a material before it is reflected to the outside. This mode is more accurate, but requires more calculation time than single scattering.

Attenuation

The distance that the light travels inside the medium is dependent on the attenuation value. The higher the value, the more light is absorbed inside the medium.

Asymmetry

This value describes the directional characteristic of incoming light, and its weighted behavior. For a value of -1, the light is distributed to the averted side along the incoming light path. FOr a value of 1, the light is distributed along the incoming light path. A value of 0 describes a homogeneous distribution of light inside the medium.

Select Medium

Offers a large selection of refraction indices, based on materials existing in reality. The selected medium affects the Index of Refraction, automatically.

Index of Refraction

Defines the optical density, and therefore, the way light is refracted when passing through differently dense materials.

The Texture, Repeat, Offset, Rotate, and Anisotropy settings are described in the Incandescence section.

Displacement

Displacement maps are detailed maps, which are interpreted as height information. Floating point displacement maps may encode displacements in both positive and negative directions using real world values. Using displacement maps you can create highly detailed structures from simple geometry by using a plain image. Each point on the geometry is displaced along the interpolated vertex normals using the height information of the map, resulting in a realistic silhouette, producing correct shadows, and reflections. Accuracy is limited by the resolution of the texture image and memory requirements are low. To avoid cracks in the displaced surfaces the vertex normals should be smooth and consistent. Using a higher tessellated base mesh can improve performance.

Displacement Height

Defines the scaling factor of values for the displacement.

Displacement Offset

Defines the offset of the displacement. Allows you to set the value of the zero plane in the texture. Values below the zero plane displace inside the geometry and values above the zero plane displace outside the geometry.

Use Accurate Silhouettes in OpenGL

This feature allows you to calculate the displacement in OpenGL like in raytracing mode. Selecting it may drastically reduce the performance.

Use Texture

Loads an image texture for the diffuse color channel. Uses the image as pattern on the surfaces.

If this option is selected for multiple texture slots of a material, their texture mapping settings are linked together. When changing, for example, the Repeat UV of the linked texture, it is changed for all linked textures at once. When selecting this option for a texture while other textures of that material already have the link option selected, the texture settings are set to the settings of the already linked textures.

Mapping Type

Select the type of mapping, either Planar, or UV.

Repeat Mode UV

Sets the repeat mode of the texture. There are four modes:

Repeat

Repeats the texture in all directions.

Mirror

Repeats and mirrors the texture on the x- and y-axis with every repetition.

Decal

The texture is not repeated.

Clamp

Repeats only the last pixel of the texture.

For Mapping Type UV

You can set the following parameters:

Repeat UV

Sets the number of repetitions for the UVs.

Offset UV

Sets the offset for the UVs.

Rotate

Rotates the UVs.

For Mapping Type Planar

You can set the following parameters:

Projection Center

Coordinates (x, y, z) of the projection plane’s center can be set here.

Projection Orientation

Offers the possibility to incline the projection plane.

Projection Size

Sets the size of the projection.

Keep Aspect Ratio (Checkbox)

If checked, the size corresponding to the original aspect ratio of the texture, is automatically adjusted.

Rotate

Sets the projection plane’s rotation on the X/Y/Z-axis.

Manipulate

Applies the texture to the selected surface.

Fit Size

Adjusts the size of the projection plane to the selected object.

Object Center

Adjusts the projection center to the center of the selected object.

Raytracing

These settings take effect in Raytracing rendering mode only.

Material ID

Sets the ID of the material in a range of [0, 31].

Line Tube Radius

Defines the radius of the tube when the shader is applied to a line geometry.

Use Local Environment

If selected, diffuse and glossy reflections are calculated from the environment that is assigned to this material in all illumination modes. Specular reflections are determined by the environment that is present in the scene.

Ignore Photon Map

Selecting this option does not include the light values of a photon map when calculating the illumination of a pixel.

Override Illumination Mode

If selected, the setting overrides the global set illumination modes for interactive or still frame rendering.

Interactive/Still Frame

Sets the render quality mode and render quality level during Render View interaction/still frame rendering.

Precomputed

This mode does not compute direct reflection, nor does it compute refraction or any other sophisticated visual effect.

Override IBL Sampling Quality

If selected, the setting overrides the global IBL Sampling quality for sampling the environment map.

Interactive/Still Frame

Sets the IBL sampling quality during interactive/still-frame rendering.

Override Reflection/Refraction Sampling Quality

If enabled, the setting overrides the global sampling quality for reflections/refractions.

Interactive/Still Frame

Sets the reflection/refraction sampling quality during interactive/still-frame rendering.

Override Trace Depth

If selected, the setting overrides the global set illumination modes for interactive or still-frame rendering.

Interactive/Still Frame

Sets the Trace Depth during interactive/still frame rendering.

Common

The common settings define material settings that are present in all BRDF materials.

Occlusion Color

Sets the shader’s pre-calculated ambient occlusion color.

Occlusion Intensity

Sets the shader’s pre-calculated ambient occlusion intensity

Compress Textures (OpenGL)

Compresses all used textures to save disk space and helps to reduce memory requirements in large scenes.

Sort Key (OpenGL)

Enables materials to be sorted into groups based on the key that controls the order of the drawing transparent surfaces.

Environment

Right-clicking opens a context menu to select an HDR image for the light source.

The HDR image of the assigned environment is used for diffuse, glossy, and specular reflections on this material in OpenGL rendering. Different materials can have different environments assigned to get different lighting effects.

In Raytracing, the handling of the environment depends on the active illumination mode.

Lighting Mode

Defines the light model to be used for the shader. There are five different lighting models.

IBL + Indirect + Direct Lights

The shader is affected by the HDR-Image, by the pre-calculated or interactive Global Illumination rendering and by the direct light sources placed in the scene.

IBL + Indirect

The shader is affected by the HDR-Image and by the pre-calculated or interactive Global Illumination rendering.

IBL + Direct Lights

The shader is affected by the HDR-Image and the direct light sources placed in the scene.

IBL

Only the HDR-Image affects the shader.

Direct Lights

Only direct light sources placed in the scene affect the shader.

Variable Rate Shading

Important:

This is an OpenGL-specific rendering feature.

Set the shading rate per material, such as coarse 2x2 or supersampling 4x. Use variable rate shading to vary the amount of processing power required for different parts of an image. The pixels where the user is looking are rendered at a higher resolution than anything in their periphery, saving processer power. Variable rate shading also provides a smoother VR experiences.

For materials with fine patterns that are prone to the moiré effect, such as carbon or HMI textures with thin lines that appear aliased, use a supersampling shading rate. If you are looking for better performance, use the coarse shading rates, which has no other purpose than that. Both of these can be used in VR and desktop mode.

E.g., all materials are rendered "normally" with the native shading rate (1 sample per pixel), but the carbon material should be rendered with supersampling (4 samples per pixel).

When using foveated rendering at the same time, the material is always rendered with its custom shading rate. For example, the carbon material is rendered with 4 samples on the whole screen, as well as in the periphery of the foveated area.

Off

Disables variable rate shading.

1 Sample

Enables variable rate shading for normal pixel shading, but no visual difference to VRS off.

1 Sample per 4 pixel

Enables variable rate shading for coarse pixel shading with 1 sample per 4 pixel.

1 Sample per 16 pixel

Enables variable rate shading for coarse pixel shading with 1 sample per 16 pixel.

2 Samples

Enables variable rate shading for supersampled pixel shading with 2 samples per pixel.

4 Samples

Enables variable rate shading for supersampled pixel shading with 4 samples per pixel.

8 Samples

Enables variable rate shading for supersampled pixel shading with 8 samples per pixel.