Viz Artist User Guide

Version 3.14 | Published October 30, 2020 ©

RTT Advanced Materials

RTT Advanced Materials plug-ins allow you to create a number of high-quality materials using state-of-the art shader technology. Using the plug-ins is very easy. Simply drag the shader plug-in of your choice onto selected geometry, assign a material and set up the additional parameters as shown by the shader in its own editor. Some plug-ins remain inactive until you have applied all necessary textures, depending on the shader plug-in. This may include a basic texture on your container and/or additional textures to be dropped in the plug-in interface. You can modify all parameters of the applied material on your object, such as Ambient Color, Diffuse, Specular and Emission, Shininess and Alpha. All these parameters also affect the shader.

All RTT Advanced Materials plug-ins (except the Bump Optimized Shader) allow manipulating the texture mapping of each texture map individually. This means you can use a different position, rotation and scaling for each texture. As for the mapping of additional textures inside the Shader, the same mapping method as being assigned to the texture on your container is used. It is also possible to change the alignment of the environment textures to achieve the correct reflections on the respective object surface.

If you do not want to use individual texture transformations, you may switch the option off. Each additional texture (except the environment texture) offers the button Enable Individual Transform. With the button turned Off, the texture mapping coordinates of the base texture is used.

RTT Shaders support up to eight light sources. The supported light types are infinite and local lights; also the light color of these lights is supported.

If you import the Viz Artist/Engine archive RTT_ShaderPresets_V1, you obtain about 60 sample scenes which are meant to give you an idea how to work with the Shaders. These presets are free to use, but in general, they are thought as a guideline for how to work with textures and the Shaders. Correctly working with the textures dramatically improves the look of your Shader. The Shaders use color maps, bump maps (in the normal map format), specular maps and cubic environment maps in HDR and LDR formats.

Creating color maps is straightforward. They are regular RGB textures that you can use either on the container or inside the Shader, depending on the Shader you are using.

Creating specular maps is also straightforward. They are grayscale textures where you define, through a gradient from white to black, where light is reflected or not.

Creating normal maps for the bump inside your Shader is not complicated either; just go to Nvidia's corporate web page and download the relevant Nvidia Photoshop plug-ins, or use this link Nvidia Texture Tools for Adobe Photoshop.

After installing the filter in question, you have a new section in the filter category in Adobe Photoshop. By applying this filter, you are shown a window with various settings (Please read the corresponding Nvidia User’s Guide); yet there is not much work involved. Just have a look at the settings in the Nvidia Photoshop plug-in Image below and start exploring them on your own.

images/download/attachments/50614601/psh_nvidia_nmf.png
Creating Cubic Environment maps is no secret either. Cubic Environment Maps can be rendered either with a preferred Render Engine (Mental Ray, V-Ray, etc.), if it should be a 3D generated environment map, or they can be created with HDR Images, which are then transformed with HDR Shop.

Note: HDR Shop has a menu for panoramic transformations, here you can create a cubic environment image by transforming it from latitude/longitude to an cubic environment by just a few mouse clicks (see instructional video).

Note: Creating Cubic Environment Maps (HDR or LDR) is a well known technique for 3D experts. This Viz Artist User Guide does not explain the creation of these Environment Maps in detail, as there are numerous tutorials on the web for this texture creation procedure.

If you do not have a license for the RTT Advanced Materials plug-ins, you may contact either one of your local Vizrt Support people or you can send an e-mail to license@vizrt.com to obtain either a time-limited demo license or a full license. Without a license, you can load the preset scenes, but you cannot modify them; only a few parameters are adjustable.

This section also contains information on the following topics:

Cube Map

Cube map textures are typically used for approximated environmental reflection and refraction. They consist of a set of six two-dimensional textures that form a textured cube centered at the origin. Unlike 2D sphere maps, they grant higher details for the whole environment. The RTT Advanced Materials plug-ins accept only cube maps as reflection textures and require them to be stored in a vertical cross layout. Cube maps can soon be created easily by using the Dynamic Texture plug-in. To achieve the best results with the Shaders we strongly recommend to create your cube maps in HDR format.

Note: The vertical cross cubemap size is required to be one of the following: 192 by 256, 384 by 512, 768 by 1024, 1536 by 2048 or 3072 by 4096 pixels, where a higher resolution indicates higher image quality. The general rule of thumb is that the contained six images need to have power-of-2 resolution.

HDR

HDR (High Dynamic Range) images can store a much wider range of brightness values than common (i.e. low dynamic range) images. Therefore, it is possible to create more brilliant highlights and reflections when using HDR images. HDR images can be shot by using special spherical cameras, or created with the aid of HDR image processing tools. Furthermore ready-to-use HDR cube maps are available as DVD collections. All plug-ins with environmental reflections support HDR cube maps. .hdr format images are supported.

Normal Map

Normal maps are textures used to calculate bump mapping. They encode surface details (i.e. the normals of a surface) as RGB color values and therefore show usually in some shades of blue. They can be created easily from (grayscale) height maps with plug-ins for Adobe Photoshop or Gimp.

Fresnel

The Fresnel effect describes how much light is reflected on a surface and how much light is refracted through this surface. At shallow angles the reflection is strong while there is almost no refraction.

RTT

All RTT Advanced Materials are developed by Realtime Technology AG. Realtime Technology AG is a worldwide leading supplier of 3D real-time visualization technologies and services for industrial applications in the automotive, aircraft and consumer goods industries.

Note: All RTT shaders can be uninstalled from the Viz Artist/Engine program menu.