NVIDIA® IRAY® is a physically based rendering technology that generates photorealistic imagery by simulating the physical behavior of light and materials. Using Iray, the animation becomes more realistic relatable to the viewers.
Images on the right are rendered with NVIDIA® IRAY®.
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Iray for SYNCHRO 4D Pro is an add-on Section available for annual subscription. Please refer to our website for detailed pricing and licensing.
Settings
- To start, we will launch SYNCHRO 4D Pro from desktop and open the Training Building Assigned.sp file. To enable the Iray plug-in (if already not enabled), go to Options, then choose Plugin Sections > Check Iray > Click OK button
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- To enable Iray 3D Viewpoint, go to 3D View Properties window, go to Raytrace Options tab.
Note: If it is disabled, you need to activate the Iray plug-in first.
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- To activate Iray mode in 3D View, right click in 3D View window, choose Render Mode > Iray.
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Alternatively, you can go to 3D View Properties window, in General tab, select Iray in the Render Mode dropdown.
The model will be noisy initially. But as time goes on, it keeps refining itself. This is how Ray Tracing, the technology behind Iray works. It keeps rendering the scene while reducing noise based on the parameters that the user provides. Once you manipulate your model, you will see the window restarts rendering. The speed and performance of rendering depends on your system’s graphic card
capabilities.
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Raytrace Options
- Render Mode
- Photoreal is an interactive, ray-tracing based render mode that generates "push-button" photorealistic imagery featuring complex global illumination effects. Iray Photoreal makes use
of a highly optimized Bidirectional Scattering Distribution Function (BSDF) and Emissive Distribution Functions (EDF) based framework, essentially capturing the physical behaviour
of real-world materials and light sources. Iray Photoreal can leverage NVIDIA CUDA capable GPUs to render photorealistic images much faster than on a CPU, due to the highly parallel
nature of the underlying simulation processes. If a system does not feature CUDA capable graphics boards it will automatically fall back to using only CPU based rendering. This will produce the same images but typically the rendering will take longer to complete. In addition, it can also use both resources at the same time.
- Interactive is an interactive raytracing render mode which uses faster yet less accurate rendering algorithms than Iray Photoreal. Iray Interactive targets a look which is consistent with the physically-based result of Iray Photoreal, yet it is optimized for interactive scene manipulations. Iray Interactive leverages NVIDIA CUDA-capable GPUs. It is ideal where ray-tracing effects, such as reflections and refraction, are desired and limited photorealism is acceptable.
- Bridge Photoreal/Interactive - remote rendering on Iray Server.
- Cluster Photoreal/Interactive - remote rendering in which 4D scene is uploaded to remote server for realistic rendering. Remote server renders scene (performance heavy process), sends to SYNCHRO encoded images, SYNCHRO receives them, decodes, fills the screen. Remote server can be Nvidia VCA or any computer with Iray Server installed. Cluster software manages rendering nodes - software compatibility, load balancing.
- Max iterations - The maximum number of samples is compared to the number of samples since the beginning of this progression. The default is 300. The number of iterations will display in the status bar at the bottom of the window.
- Max seconds - The maximum time in seconds is compared to the rendering time since the beginning of this progression. It defines the time an image will render. The default is 300.
Note: The rendering will stop when either Max iterations or Max seconds is met, whichever comes first.
- Time of day - adjust the time to set the position of the sun for the rendering.
- Sun altitude - adjust the altitude of the sun to adjust for season and location.
- Sun brightness - adjust the brightness of the sun to be used as the light source in the rendering.
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- Camera exposure - adjust the exposure to suit indoor or outdoor locations
- Export without animation (fast) - disable to prevent rendering of growth simulations for faster performance
- Instancing (less RAM) -Rule of a thumb - enable for scenes that occupy more than 5GB of RAM.
- Render frame batches - When checked will cause 3D window to update when the best quality is reached instead of update for every iteration. Use for VCA (Cluster Photoreal mode) to minimize network communication cost.
- Mouse look - When enabled, Mouse look mode is used to move camera in first person view with WASD keys. When disabled, Mouse orbit selects target object and rotates camera around it.
- Use cached results - When checked will try to use cached results during export if required view cache exists.
- Enable denoiser - If set, the denoiser will process the rendered image. Enabling the denoiser may consume significant memory and performance.
- Denoiser start iteration - If the denoiser is enabled, this option will prevent denoising of the first few iterations, with the value specified in this option being the first denoised iteration. This can prevent the denoiser's performance overhead from impacting interactivity e.g. when moving the camera. Additionally, the first few iterations are often not suitable as input for the denoiser due to insufficient convergence, leading to unsatisfactory results.
Applying Iray Material
To apply Iray materials, you need select the 3D objects that you would like to apply Iray material to first. Then go to 3D Properties window > Select Raytrace Material tab. There is a list of commonly used material texture in SYNCHRO 4D Pro, such as asphalt, brick, concrete, etc.
You can also change the texture scale under Properties by type in the texture scale field. Make sure you click the Assign button. You can also change the texture scale under Properties by type in the texture scale field. Make sure you click the Assign button.
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Iray Rendering
- To export an Iray rendered image, Go to Reports ribbon then click Render in Iray. In Render in Iray popup window, you can customize the image size [pixels], define Image Filename and click Browse to save to a location. In the end, you can click OK button to start the export.
How fast the image is rendered will depend on your computer graphics card capability. You can reduce the size of the image to get a faster speed.
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- To export an animation in Iray
- You can select the animation that you would like to export in the Animation window, right click to choose Export AVI.
- In the Export Animation… window, go to Content tab, make sure there is at least one 3D View is included and visible in the preview.
- Set Max iterations per frame and Max seconds per frame both to 1, then check the option Raytrace with Iray.
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- Check the preview and make sure it looks good. Then recommend to change Max iterations per frame to 20 and Max seconds per frame to 150.
- A progress bar will show up. It will disappear when the preview of the rendered frame is displayed in the preview.
- You can click the OK button to start the export.
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