Below is a list of features supported and unsupported in this phase one release of XPU
...
Shading
| BxDFs & Patterns | RIS | XPU | Notes |
|---|---|---|---|
PxrSurface | ✅ | ✅ | Some Subsurface modes are not available |
PxrLayerSurface | ✅ | ✅ | |
PxrDisneyBsdf | ✅ | ✅ | |
PxrMarschnerHair | ✅ | ✅ | |
PxrConstant | ✅ | ✅ | |
Lama | ✅ | ❌ | |
Volumes | ✅ | ❌ | |
OSL Patterns | ✅ | ✅ | PxrDirt & PxrCurvature not supported |
C++ Patterns | ✅ | ❌ | |
Baking | ✅ | ❌ | |
Point Clouds | ✅ | ❌ |
...
| Info | ||
|---|---|---|
| ||
| As the light selection scheme in this phase one release of XPU is yet to be implemented, we recommend keeping the number of lights in your scene to a minimum, preferring to look develop your assets illuminated via a single PxrDomeLight for example. |
...
...
Geometry
| Geometry | RIS |
|---|
...
| XPU | Notes | ||
|---|---|---|---|
Subdivision Surfaces | ✅ | ✅ | Catmull-Clark only |
Polygonal Surfaces | ✅ | ✅ | |
Nurbs | ✅ | ❌ | |
Curves | ✅ | ✅ | |
Points | ✅ | ✅ | Some features not available |
| Quadrics and Blobbies | ✅ | ❌ | |
| Nested Instancing | ✅ | ❌ |
Notes :
- Loop Subdivision. Catmull-Clark for both quads and triangles is supported
- Points. Have been partially implemented. Point falloff is not yet supported
NURBS
Quadric
Blobbies
The built-in curvature doesn't match RIS and will be receiving enhancements in a future release
Nested instancing- Object attributes such as maxdiffusedepth and maxspeculardepth not yet implemented
...
- numBxdfSamples, numLightSamples, numIndirectSamples (and their manually set counterparts) are not supported.
- PxrOcclusion, PxrVisualizer and PxrUnified are not yet supported.
- clampDepth and clampLuminance (used to suppress fireflies) have not been implemented
- Russian Roulette has not been implemented
- allowCaustics is always 1
...
Rendering
Notes :
- XPU currently only outputs EXR or TIFF frames
- PxrCamera not supported yet.
- Adaptive sampling is yet to be implemented
- Motion blur has not been fully implemented
- Trace Subsets have not been implemented. This then impacts the subsurfaceSubset feature of PxrSurface
- Volumes not yet implemented
- User defined AOVs or LPEs not yet implemented
- Only some geometric built-in AOVs are available under the same name they are available for RIS
- Holdouts, shadow collectors not yet implemented
- Deep Output. Coming soon.
- Multi-camera, multi-frame are not yet supported
- PxrOcclusion, PxrUnified integrators are not supported.
- The built-in curvature calculation different is different to RIS, which results in differences in specular mollification.
- The "weighted" option for the pixelfiltermode parameter to the Hider is not yet supported.
- Procedurals not supported. However, if you are using the latest XGen in Maya, you should get renders of your data.
- Baking - either at the pattern level via PxrBakeTexture or at the renderer level to bake global illumination is not yet supported.