Maya - Render Settings

Owned by Former user (Deleted)
22 Sept, 2016
7 min read

In order to use Maxwell for rendering from Maya, open the Render Settings panel and select Maxwell Render in the renderer dropdown. This section documents only the Maya-specific settings; for an explanation of the common Maxwell render options, please see this page.

Common Tab

The plug-in takes into account all the output file name settings that are found in the Common tab of the Render Settings panel. However, make sure that the file name format (the Frame/Animation ext dropdown) is set to end with the extension, as Maxwell determines the output image codec based on the file extension. Do not use name (single frame), name.ext.# or name.#. Also, Maxwell cannot write output files which contain more than one frame (such as AVI or MOV), so the two Multi Frame options at the end of the list are not supported.

The plug-in filters the Image format dropdown to leave only the formats supported by Maxwell. Currently, these are: PNG, JPG, TGA, BMP, TIFF, EXR, HDR and JP2. Since EXR, HDR and JP2 are not natively supported by Maya and there is no official way for plug-ins to add extra entries, these formats reuse the codes which are normally assigned to PSD, DDS and Multi-layer PSD, respectively. This is why the computed file name displayed at the top of the panel shows the wrong extension when EXR, HDR or JP2 are used. However, this is only a display issue in this panel, the output file will have the correct extension.

The color management settings from this tab are not used. The output color space can be set in the Tone Mapping group, under the Maxwell Render tab.

When rendering the current frame, Maxwell will use the camera attached to the active viewport. In batch mode, it will render one image for each camera listed in the Renderable Cameras group. When multiple render cameras are defined, the output images for each camera will be placed in separate subdirectories of the output path.

General Settings

Click here for a description of the Maxwell render options, such as Sampling Level, Multilight etc. The following settings are specific to the Maya plug-in:

Global Scale Factor

All the positions and distances in the scene will be multiplied by this value on export. Since the plug-in handles unit conversions automatically, this setting should only be modified in scenes which were not modeled to scale. In Maxwell, the size of the objects influences several aspects of the rendered image such as depth of field, transparency and subsurface scattering, so it is important to maintain a realistic scale in order to obtain accurate results.

Attenuation Scale Factor

This factor is multiplied into all the material attenuation values. Modifying the global scale changes the thickness of the objects in the scene, so transparent objects can change appearance due to increased or decreased attenuation. You can use this setting to tweak the scene if the attenuation settings are not to scale. However, same as with the previous setting, it is better to input realistic attenuation values for the materials, and leave this parameter at 1.

Displacement Scale Factor

All the absolute displacement height values are multiplied by this number. Materials using relative displacement height are not affected, since in that case the displacement is proportional to the size of the object.

Motion Type

Set what kind of motion is exported for motion blur:

  • Off: no motion blur is computed.
  • Movement + Deformation: full motion blur, using both changes in the object positions and local deformation such as skinning.
  • Movement Only: deformation is not exported. Some scenes can export faster in this mode and the render performance can improve as well.

Motion Steps

Set the number of positions exported for each object during the exposure interval. Maxwell will interpolate the movement between these positions. For linear motion, two steps are enough to reconstruct the correct path at render time. For more complex motion, such as objects following an irregular path, you will need to increase this parameter to obtain the desired result in the render. Using more steps slightly degrades rendering performance and can slow down the export process.

Shutter Open Offset

Offset the shutter open event in time relative to the current frame. When this parameter is 0, the camera shutter opens at the start of the frame and closes in the future. When the value is 1, the shutter opens in the past and closes at the current frame. To center the shutter interval on the current frame, so that half the exposure interval passes before the frame and half after, set this parameter to 0.5 (this convention is used in many cases when motion blur is computed).

Read Back Multilight

When Multilight is on and this option is checked, the plug-in will attempt to import emitter changes made during the render back into the scene. When the render finishes, you will be presented with a dialog where you can select which changes to read back:

After the Import button is clicked, the plug-in prints the changes that are made to the scene in the script editor.

Additional Flags

The contents of this box are passed verbatim on the command line when Maxwell is executed.

Persistent MXS / MXS Path

When rendering with Persistent MXS off (the default), the plug-in writes the scene to a temporary file which is removed after the render is finished. Enabling this option will leave the exported file on disk. This is useful if you ever need to resume or redo a render. If the MXS Path control is empty, the output scene path is computed by replacing the image file extension with MXS.

Specify MXI Path / MXI Path

Normally, if MXI writing is enabled, the path to the MXI file is computed by replacing the extension of the output image file with MXI. These two settings allow you to override the location of the MXI file written during rendering.

Render View Text

The text specified in this box is printed over the image in the Render View. The text is not saved in the image file produced by Maxwell, but it will appear if you manually save the image from the File menu of the Render View. The plug-in recognizes a number of keywords when they are enclosed in <>:

  • startDate: the calendar date when the render command was issued, formatted as YYYY-MM-DD

  • endDate: the date when the render finished (more precisely, when Maxwell was closed)
  • startTime: the time when the render was started
  • endTime: the time when the render finished
  • renderTime: the total render time
  • n: a newline
  • any of the attributes of the render options node, prefixed with g_

For example, to print the name of the HDR background image, followed by the render time on a separate line, you can use this string:

   Image: <g_environment[0].envTexture><n>Render time: <renderTime>

The result will look similar to this:

Region Mode

When region rendering is requested, this setting controls the resolution of the region. There are two possible values:

  • Region: the exact area defined in the render view is used.
  • Blow up: the region is rendered using the full frame resolution, adding black bars as necessary to preserve the aspect ratio.

See here for examples.

Maya Instances to Maxwell Instances

When this setting is on, the plug-in will export Maya instances as render instances. When it's off, Maya instances are exported as copies. The Maxwell instancer node will always produce render instances, regardless of this setting.

Environment

Maxwell environment lighting settings are described in detail on this page. There are only a few Maya-specific settings:

Activate Viewport Preview

This will show a preview of the environment in the Maya perspective viewports. The display mode must be set to shaded, textured or lit for the preview to become visible.

Sun Direction

This setting can have two values:

  • Compute from Geographical Location: the sun direction is determined from the longitude, latitude and time settings found in the Geographical Location group.
  • Track Object: the sun direction will be determined from the orientation of an object in the scene. It is usually best to use a directional light for this purpose, as it provides an intuitive way of visualizing the direction. The name of the object to use can be typed in the Track Object field, or a list of compatible objects can be brought up by clicking the map button next to the field. The Track Selected Object button can also be used to load the name of the currently selected object into the field.

Environment Preview Channel

When the Image Based Environment is used and the viewport preview is enabled, this setting determines which of the 4 IBL channels is displayed in the viewport: background, reflection, refraction or illumination.

Same as background

This option can be found in the reflection, refraction and illumination channel groups. When it is enabled, the respective channel uses the same parameters as the background, and the channel-specific settings are ignored.

Render Channels

There are no Maya-specific settings in this group. See the Channels page for a description of these options.

Render Layers

This group allows you to select which kind of lighting is computed by the render. 

SimuLens

There are no Maya-specific settings in this group. See the SimuLens page for a description of these options.

Maya Lights

This section allows you to control how built-in Maya lights are exported. See this section for more details on this feature.

Use Maya Lights

Uncheck this if you don't want built-in lights to be used by Maxwell.

Intensity Scale

The intensity of the lights is multiplied by this value on export. An intensity scale is also provided on each light node, for object-level adjustments. The two scaling factors are multiplied together.

Point Light Geometry

Specify a MXS file to be used as the geometry for point lights. If this field is empty, the plug-in automatically generates the appropriate geometry for each point light. When a MXS file is used, all the objects whose names start with "emitter" receive the generated emitter material. If no such object is found, the emitter material is applied on all the objects from the MXS file.

Spot Light Geometry

Same as above, except for spot lights. The naming convention used for applying the emitter material is particularly relevant here, since spot lights usually have a light emitting part and an enclosure/occluder part, and you only want the generated emitter material to be applied to the emitter part.

Area Light Geometry

Same as above, but for area lights.