Parameters for both ActiveShade Mode and Production Rendering Mode are described below , but note that some parameters are available only for ActiveShade Mode.
CPU – The CPU engine is used. This engine does not require a graphics card and supports many of the regular V-Ray renderer features, including procedural textures and complex materials.
OpenCL – A GPU engine based on OpenCL is used. This engine uses graphics cards that support OpenCL and can be very fast depending on the hardware, but has somewhat limited abilities with regards to shaders. The OpenCL and CUDA engines have the same set of capabiltitiescapabilities, but for NVIDIA GPUs it is recommended to use the CUDA engine.
CUDA – A GPU engine based on the NVIDIA CUDA platform. This engine uses NVIDIA graphics cards that support CUDA and is the recommended engine for NVIDIA GPUs. Like the OpenCL engine, it can be very fast depending on hardware , but has limited abilities with regards to shaders. The OpenCL and CUDA engines have the same set of capabilities. The recommended choice for NVIDIA GPUs.
This sub-section of parameters is only active when the Engine type is set to a GPU option (CUDA or OpenCL).
Coherent tracing – When enabled, V-Ray RT will attempt to spawn secondary rays (GI, reflection etc) in similar directions in order to improve rendering speed on certain GPUs.
GPU textures – Determines how textures' resolution/size will be handled to help optimize memory usage. This parameter is only effective when Type is set to Open CL or CUDA.
Disabled – Stereo rendering and additional display is are disabled, and a single image is rendered in the ActiveShade window.
Left/Right – The left and right views are displayed in separate windows that can be maximized on different displays.
Interlaced – A separate window displays an interlaced blend of the left and right eye images. This is useful for displays that support interlaced stereo.
Checkered – A separate window displays a checker blend of the left and right eye images. This is useful for displays that support checkered stereo.
Anaglyph (Red, Cyan) – A separate window displays a red/cyan anaglyph preview of the stereo images. Matching anaglyph glasses are required to view the stereo effect.
Anaglyph (Green, Magenta) – A separate window displays a green/magenta anaglyph preview of the stereo images. Matching anaglyph glasses are required to view the stereo effect.
OpenGL stereo – A separate window alternates between the left and right eye images. Matching active shutter glasses and supporting video card are required to view the stereo effect.
Duplicate (mono) – Duplicates the contents of the ActiveShade window so that it can be maximized on another display. This is not a stereo mode.
In-process RT engine – When enabled, the actual rendering of the image happens inside the 3ds Max process. This speeds up the initial scene translation phase and improves the interactivity of ActiveShade rendering. When disabled, a separate V-Ray standalone render server is launched in DR mode to perform the actual rendering. This option might need to be disabled if V-Ray RT cannot find suitable GPUs for rendering with the CUDA or OpenCL engines. An example is when there are both an AMD and an NVIDIA GPU installed in the machine, and the AMD GPU is used for handling the user interface and 3ds Max viewports whereas the NVIDIA GPU is only used for rendering.
Eye distance – The distance between the two virtual stereo cameras, in world units. The cameras are always focused at on the camera target for the current view.
Note: By default, the focus type is shear, where each eye's view is sheared along the Z axis so that the two frustums converge at the fusion distance. The internal parameter for changing the focus type for this display to another type (such as rotate or parallel) is accessible only through MaxScript.
Don't render (just export) – Allows the scene to be only exported without being rendered. The ActiveShade session will be closed as soon as the .vrscene file is created. Note: currently Currently the scene is exported only for the current frame, without animation. Animation can be exported using the settings in the .vrscene export command from the Max Quad menu.
V-Ray RT GPU Render Devices Select
This rollout is shown whenever the V-Ray RT engine type is set to OpenCL or CUDA to specify which GPU devices to use for in-process rendering. It is equivalent to the external utility Select OpenCL devices for V-Ray RT GPU that is included with V-Ray (ocldeviceselect.exe) , but allows the devices to be changed without restarting 3ds Max.
Selecting specific devices to render with can help if you have multiple GPUs and you want to leave one of them free for working on the user interface or you may want to combine your CPU and GPU together for Hybrid Rendering.