Advanced Rendering Workflow

You can set up your display with photorealistic graphics.

Start advanced rendering:

Set the number of threads available for advanced rendering using one of the following techniques:
- The user interface:
  1. Select Tools > Options.
  2. In the left window of the dialog, select the Services > Visualization node.
  3. Enter 9999 for the Number of Client Render Threads property. This entry causes Simcenter STAR-CCM+ to determine automatically the maximum number of processes that you can actually set.
  4. Click Close.
- The command line, for advanced users (the following example is a typical set of line commands):
```
% starccm+ -batch -rthreads <number of threads>
```
  The value specified with the -rthreads command line option takes precedence over the corresponding setting that is available through Tools > Options.
  
  The default value for -rthreads is 1 if you do not specify a value. When you use the -batchsystem option, -rthreads is restricted to 1.
If you specify a high value for render threads, you can incur resource contentions that interfere with the proper functioning of your computer.

Increasing render threads is expected to scale performance linearly. However, linear scaling can fail with high thread counts on hyper-threaded or multi-CPU systems, although performance can still increase. Complexity of the scene can also impact performance and prevent scaling.
Within the Scenes node, select the scene object on which you want to apply advanced rendering and activate Enable Advanced Rendering.
The initial rendering resembles the normal Simcenter STAR-CCM+ visualization mode (OpenGL).

Set up the rendering:

To changes settings that apply to all displayers in the scene, expand the scene node and select the Attributes > Advanced Rendering Properties node. The key setting is the Quality property; a higher value requires longer rendering time, and Simcenter STAR-CCM+ shows an estimate of the time in the scene. For details, see Advanced Rendering Properties.
In particular, the Shadow Override property lets you control whether you apply the same set of shadow characteristics to the entire scene, or customize the shadows for each displayer.
To apply rendering effects on objects within a scalar displayer, select the [scalar displayer] > Advanced Rendering Effects node (for details, see Advanced Rendering Reference):
1. Use the properties of this node for the following:
  - Casting effects onto other surfaces; including shadows, reflections, and refractions
  - Removing transparency, self-shadowing, and self-reflection
  - Allowing shadows for the parts in the displayer
  - Shadow sharpness
2. Select the Advanced Rendering Effects > Advanced Rendering Materials node. These material options let you apply more custom settings in the displayer. These settings are not available if you set the Color Mode of the displayer to Preset Material.
3. Select a type of rendering material from the drop-down list in the Effect property.
  
  Depending on your choice, a sub-node is available for you to specify more settings. For example, the Metallic sub-node includes specular color and roughness.
  
  Note Photorealistic metal surfaces do not use RGB colors.
If the scene takes time to render, text appears with the estimated time to completion. During this time, you can still interact with the scene.
When you generate a hardcopy of the scene with advanced rendering, the Save to File dialog also includes an estimated time. The time estimate is based on the duration of the previous render pass, when available.
If you want to apply a preset material to the surfaces defined within a displayer:
1. Select the displayer node and set Color Mode to Preset Material.
2. Select the Preset Material sub-node of the displayer node and choose from the drop-down list of the Material property.
Note If you choose the Preset Material setting, you do not have the use of the Advanced Rendering Effects > Advanced Rendering Materials node.
Decide whether you want to use a light-emitting material as a light source. Light-emitting, or emissive, materials allow you to add dynamic lighting effects, or can serve as a fixed light source.

Although an emissive light source cannot explicitly follow a moving surface, you can set up this effect since the emissive light source is applied to a part. To do this, set up a transform, coordinate system, or Java macro that moves the part in conjunction with the moving surface that you want to illuminate.

To make an light-emitting part invisible, set the Opacity property of its displayer to 0. The object becomes invisible but its light remains.
If you want to define an additional preset material, do one of the following:
- Right click the Tools > Rendering Materials node and select a type of material from the New Rendering Material submenu. The node of the new material appears in the appropriate subfolder.
- Expand the Tools > Rendering Materials node, right-click a subfolder of one of the material types, and select the menu item for a new material, for example New Metallic Material.
Enter the characteristics of your new material in the properties of the node. For details, see Rendering Materials.
There are 7 different categories of materials, ranging from simple models that are fast to evaluate (Non-Physical), to empirical models (Metallic, Matte) that are intuitive to configure, to physical models (Metal) that can be specified exactly from measurements. You can also specify materials that absorb all incidents but emit their own light (Light-Emitting). These materials are expected to cover all important material categories that can be encountered in rendering.
Note If you want to create a material that is similar to one of the supplied ones, make a copy of that node, and then edit its properties.
To smooth the edges of the mesh, which is often necessary for a realistic rendering of water, select the Shading Angle sub-node of the displayer. Adjust the slider in the Shading Angle property; angles above that value are not smoothed.
Decide whether to use a photorealistic environment map in your scene. See Setting the Scene Background or Environment Map.
For improved performance when writing scenes to file during batch runs, you can write to the same .sce file each time and then export individual .png files from the .sce file afterwards. See Viewer File Transform Utility scetopng