Advanced information

The following information is for advanced users of mental ray and mental ray for Maya.

Custom nodes

The following node types are added to Maya after loading the plug-in and opening one of the mental ray editors:

Nodes of these types are under control of mental ray for Maya and the user interface extensions. With the help of specialized editors the attributes of these nodes can be manipulated and custom connections can be made.

The mentalrayOptions and mentalrayFramebuffer nodes are used to hold most of the settings and properties to control the rendering options of mental ray. A number of convenient presets are available to start with. New nodes can be created within the Render Settings window. Their values are initialized to the default settings of mental ray for Maya, if appropriate. Existing nodes can be deleted as usual in Maya; they are removed from the UI the next time the Render Settings window are forced to update.

The mentalrayOptions node is the main entry for manipulating quality, performance, and features of mental ray.

The mentalrayFramebuffer node determines the output properties of the final image, like resolution, aspect, data type and image format. This way, any information of a rendered framebuffer can be saved to an output file. It's important to note that the Maya camera carries other attributes that are respected during image generation: if the Z Depth attribute is enabled then a depth file are rendered additionally to the usual color image. It gets the same name as the image file with "Depth" appended. This is saved in the mentalDepth proprietary file format, which can be viewed and converted with the imf_disp and imf_copy tools provided with mental ray. There is a way to change the default depth image format.

The mentalrayText node is used to hold custom mi text. It's the basis for the current implementation of custom shader support.

In general, those attributes that are guaranteed to be supported and recognized in the plug-in are exposed in the user interface with a descriptive name. Most of the attributes of the Render Settings node mentalrayGlobals are working similar to the matching ones in the Maya Render Settings. For details about the mental ray Render Settings, see Render Settings window.

The mentalrayCurveApprox, mentalrayDisplaceApprox, mentalraySurfaceApprox, and mentalraySubdivApprox nodes hold information regarding mental ray approximation of geometric entities. They should be handled and applied with the help of the Approximation Editor.

Custom Commands

The following additional commands are available in Maya after loading the plug-in:

The Mayatomr command executes the main functions of the plug-in. It controls the actual translation of the scene animation, takes care of the rendering and preview inside Maya. The MayatomrJob command is used to call MEL procedures on certain plug-in events. The miProgress command is used to display export progress in Maya, and can be used to interrupt the translation by pressing the Escape key. Both commands are executed and controlled via the custom user interface.

Note: The mental ray Production Shader Library is a part of the Maya install for the convenience of advanced users who may wish to integrate them into their pipeline. However, the use of this shader library is not a supported workflow within Maya.