Full Spectrum Rendering in RPR for Maya¶

Full spectrum rendering (FSR) provides artists with a rendering framework that can be easily scaled from super-fast rasterized to fully path traced, all with physically accurate materials and lighting.

FSR aims to fill the gap between the OpenGL viewports and full path-tracers . It uses Vulkan to achieve fast rendering with rasterization and to increase the rendering performance using the GPU. It also allows artists to add ray tracing effects for advanced viewport rendering, or switch to Vulkan-powered biased ray tracing or OpenCL full path tracing rendering modes.

FSR is meant to help artists to obtain a more interactive experience for viewport rendering and accelerate their work as much as possible, while maintaining physically correct lighting and shading. By switching between the FSR modes, users can easily balance the ray tracing visual quality against the rasterization performance based on their needs.

The Render Modes in Detail¶

FSR offers four render modes to support all stages of the rendering pipeline —from standard viewport creation to the final quality render.

Render Mode	Powered by	Runs on	Description
Low	Vulkan	GPU	High-performance rasterization mode for standard viewport creation. This is the fastest of all the modes, and is highly optimized for changes in geometry, material and lighting. Global Illumination effects will be less visible in this mode.
Medium	Vulkan	GPU	Hybrid mode for advanced viewport creation: rasterization with biased GI. This mode adds ray traced effects, such as reflection, refraction, ambient occlusion, etc.
High	Vulkan	GPU	Vulkan-powered ray tracing mode for look development and biased photorealistic rendering.
Full	OpenCL	CPU/GPU	OpenCL full path tracing mode, which is optimal for final quality renders, and for rendering complex scenes and materials.

Supported Hardware¶

Three of the four FSR modes run on top of Vulkan. Therefore, a Vulkan-compatible GPU is required.

Officially supported GPUs for Vulkan-powered FSR modes are:

AMD Radeon™ PRO W6000 Series (Radeon PRO W6800, Radeon PRO W6600, and Radeon PRO W6600M)
AMD Radeon Vega (Radeon Pro WX 9100, Radeon RX Vega 8/56/64/64 Liquid Cooled and subsequent models)
AMD Radeon 2nd generation Vega (AMD Radeon VII and subsequent models)
AMD Navi class cards (Radeon RX 5700 XT/RX 5700/RX 5000, Radeon Pro W5500, AMD FirePro W5000 and subsequent models)
Limited support for Polaris cards Radeon RX 500 series as well as Radeon Pro WX 7100 and WX 3200

Apart from these, FSR may run on other GPUs that are not officially supported.

Note

If no GPU is detected on the system or the detected GPU does not support Vulkan-powered FSR modes, AMD Radeon ProRender will use its default Full OpenCL ray tracing mode, and the other FSR modes will not be available.

Supported Platforms¶

FSR is supported only for Windows 10
On macOS, only the Full mode is supported.

Choosing Render Quality Mode¶

FSR modes are available in both the viewport and the final render. By choosing between the render quality modes, users can balance the visual quality of the output against performance based on their needs.

To choose the render quality mode:

Open the Render Settings window.
Switch to the Quality tab.
In the Final Render Quality and Viewport Render Quality sections, choose the necessary FSR mode.

Limitations¶

In terms of supported plug-in features, FSR Vulkan-powered modes are somewhat different to the OpenCL full path tracing mode. While the OpenCL path tracer supports all of the plug-in features, FSR modes that run on top of Vulkan have a set of limitations. These limitations are outlined below.

Quality¶

Render Quality can be controlled using the Total Ray Depth parameter.

Ray depth values for some specific surface types) as well as Ray Cast Epsilon, Clamp Radiance options are not supported.

Sampling¶

The only supported sampling mode is fixed sampling. Adaptive sampling is not supported.
Tiled rendering is not supported.
Anti-aliasing filters are not supported.

Render Passes (AOVs)¶

Supported render passes are:

Depth
UV
Object Index
Material Index
World Coordinate
Shading Normal
Diffuse Albedo
Background

No other render passes are available in the UI when you switch to any of the FSR Vulkan-powered modes.

Viewport Render Modes¶

Render modes in the viewport are not supported.

Lights¶

Since they are adapted for Vulkan-powered modes, some of the light sources and their parameters might look a bit different than in the OpenCL full path tracing mode.
For the area light source, only the rectangular shape is supported.

Camera Effects¶

Motion blur and depth of field effects, as well as camera shift are not supported.

Denoiser¶

All denoiser filters are supported, except for the Machine Learning filter.

Note that FSR Low and Medium modes use denoising internally to speed up rendering, and yield little to no noise in the render output. The denoiser will mostly be required for the High FSR mode, as this mode might render noisy outputs.

Shading¶

The following nodes are not supported or only partially supported.

Node	Details
Bump 2d	Not supported.
File	Only file input is supported.
Place2dTexture	Only default tiling is supported.
RPR Ambient Occlusion	Not supported.
RPR Blend	Not supported.
RPR Arithmetic	Not supported.
RPR Material	Supported with limitations.
RPR Uber	Supported with limitations.