Enhancements to Standard Features

The primary interface to the mental ray renderer consists of rollouts on the Render Setup dialog. To choose the mental ray renderer, use the Assign Renderer rollout, as described in this procedure.

In addition, object properties, lights, and the Material Editor have additional controls to support mental ray rendering. Last but not least, 3ds Max Design offers a special mr Proxy object for speeding up rendering of large, complex scenes.

Object Properties Enhancements

Parameters on the mental ray panel of the Object Properties dialog support displacement as well as the mental ray indirect illumination features: final gather, caustics, and global illumination.

mental ray Proxy Object

When working with high-resolution geometry, you can save memory and translation time by using the special mr Proxy object as a stand-in for your models.

Light Object Enhancements

Along with the mental ray renderer, mental ray-specific area light objects and light settings are provided.

Light Objects

The area light is a feature of the mental ray renderer. Instead of a point source, it emits light from a broader area around the source. There are two basic types of mental ray area light: mr Area Omni Light and mr Area Spotlight. An additional, special-purpose mental area light is the mr Sky Portal. Area lights create soft-edged shadows. This can help improve the realism of your rendering.

NoteTo render soft-edged shadows, shadows must be ray-traced, not shadow-mapped: see the Renderer panel Shadows & Displacement Rollout.

In 3ds Max Design, area lights are created and supported by the MAXScript scripts, light-mentalray_areaomni.ms and light-mentalray_areaspot.ms. Both scripts are found in the \stdplugs\stdscripts\ folder within 3ds Max Design install directory. Because of this, when you create an area light, you actually create a target spot or omni light for which the mental ray renderer uses the parameters on the Area Light Parameters rollout. If you render with the default scanline renderer, the light behaves like any other target spot or omni light. (You can change a light from one type to another using the Type drop-down list on the light’s General Parameters rollout.)

For area lights rendered with the mental ray renderer, you can still set and use other lighting parameters, such as color, the Multiplier value, the spotlight cone, and so on. Shadow maps are an exception. The mental ray renderer ignores the light's local shadow map settings. Area lights always use ray-traced shadows.

TipYou can use a MAXScript utility to convert standard 3ds Max Design light objects to area lights, as described in this procedure.

Light Settings

The mental ray Indirect Illumination rollout has been added to light objects to support the mental ray renderer’s indirect illumination effects of caustics and global illumination.

The mental ray Light Shader rollout has been added so you can add mental ray light shaders to light objects.

ImportantTo see the mental ray rollouts for lights, you must use mental ray Preferences to enable mental ray extensions. These rollouts appear only on the Modify panel, not on the Create panel.

Camera Enhancements

On the Parameters rollout, a “Depth Of Field (mental ray)” choice appears on the Multi-Pass Effect drop-down list to support the mental ray renderer's depth-of-field effects. To use this, turn on both Enable in the camera's Multi-Pass Effect group (default=off), and Depth Of Field on the Render Setup dialog Renderer panel Camera Effects rollout.

You can also assign mental ray lens, output, and volume shaders to cameras. These controls are also on the Render Setup dialog Camera Effects rollout. (This rollout also contains some contour-shading controls.)

NoteWhen you use the mental ray renderer, reflected or refracted light rays do not always respect a camera's clipping planes (set in the Clipping Planes group of the Parameters rollout). Also, large clipping-plane values can cause poor quality in the rendering of shadow maps. To fix this, narrow the clipping range or switch to ray-traced shadows.

Material Editor Enhancements

The Material Editor works as it does with the default scanline renderer. Certain materials and maps, or some of their controls, aren't supported by the mental ray renderer; see 3ds Max Design Materials in mental ray Renderings.

By default, the Material Editor sample slots use the currently active renderer: typically this is either the default scanline renderer or the mental ray renderer. You assign the renderer for sample slots with the Render Setup dialog Common panel Assign Renderer rollout.

When mental ray extensions are enabled (using mental ray Preferences) and the mental ray renderer is active, the Material Editor displays these additional mental ray features: