Sometimes V-Ray for Maya may fail to load automatically when Maya is launched. In this case, V-Ray must be loaded manually from the Plugin Manager. This is most commonly caused after Maya has exited unexpectedly (after a crash or when forcefully killed) in which case Maya fails to write its preferences and configuration properly. For additional help on this process, please see the V-Ray Configuration page.
Creating a new scene in Maya when Maya Software is the default renderer can result in an error on Windows and mac OS XmacOS, which can be safely ignored. On Linux, it can cause the Common tab to appear empty, in which case switching to another tab and then back to the Common tab should resolve the problem. This should be resolved with Maya 2018 and later, but older versions of Maya may exhibit this behavior.
Manually unloading and then re-loading the V-Ray for Maya plugin may cause Maya to crash.
The Outliner in Maya 2019 may not show sets, including V-Ray sets such as VRayDisplacement, VRayObjectProperties, Light Select render elements, etc. We recommend updating your Maya version as soon as an update is available from Autodesk. As a workaround, applying a filter in the Outliner and then removing it will force a refresh and the sets will appear.
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Fancy Bullets
type
circle
V-Ray lights cannot be represented in Viewport 2.0 with DirectX, but shaders are supported starting with V-Ray 3.6. It is recommended to use OpenGL in Windows > Settings/Preferences > Preferences > Display > Viewport 2.0.
In Maya 2016 Extension 2 (Maya 2016.5) on Linux and mac OS XmacOS, the OpenGL Legacy mode doesn't work properly.
In Maya 2016 Extension 2 (Maya 2016.5), the V-Ray lights have no viewport representations (this is currently under development).
Further support for the OpenGL Core profile(s) is under development.
In Maya 2017, support for V-Ray lights in Viewport 2.0 is disabled on purpose, because a bug in Maya causes a significant underperformance. This means that in Maya 2017, V-Ray lights will not illuminate Viewport 2.0, but the Legacy Default Viewport will still work as before.
Instanced V-Ray lights can lead to a dramatic slowdown in Maya's Viewport 2.0 when there's many light instances. For scenes with a lot of instanced V-Ray lights, the Legacy Default Viewport will provide better performance.
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Fancy Bullets
type
circle
Motion blur for NURBS surfaces when they are dynamic geometry.
Rendering of orthographic views in IPR rendering mode is incorrect.
The MDL Material in Maya 2015 on mac OS XmacOS.
In some rare cases, Adaptive Lights might produce artifacts when used with V-Ray GPU within Distributed Rendering.
