Working in Maya in different scales

Sometimes you may want to change Maya's default settings, either to simplify workflows that involve software that uses a different scale, or to correspond with other measurements, for example, Imperial units.

You can change the default working units in Maya, which are in metric, but it is recommended to leave them unchanged as some tools in Maya have a set type, for example, Nucleus and Bifrost are hard-coded so that 1 unit = 1 meter, regardless of working units. Instead, do not change Maya's default working units and adjust your grid to align with the scale of the project you are working on.

Unreal Game Engine

To change Maya's grid lines so they match the Unreal game engine

  1. Make sure that your Maya working units are set to centimeters (the Maya default), as 1 Unreal Unit (uu) is 1 centimeter (cm). (Change the Working Units in the Settings preferences section of the Settings/Preferences window.)
  2. Open the Grid options. (Display > Grid > ).
  3. Set Grid Lines Every to 10.000.
Note:

Unity3D Game Engine

Unity3D and Maya both use metric working units, so there is no need to change Maya's Working Units.

However, when you export to Unity, also set your export settings to centimeters in the FBX Export window. This ensures that your scene units are in meters, and your export settings are in centimeters so that when you bring your scene into Unity3D, the scale factor is 1 instead of 0.01.

Scaling for 3ds Max

3ds Max has two unit settings, System and Display. But unlike Maya, 3ds Max uses inches as its working unit. But changing the Display units to centimeters while leaving the default system units of inches in 3ds Max unchanged creates problems when exchanging files between other software applications.

When you move data between Maya and 3ds Max, the .fbx format is used and in this case, change your 3ds Max System Unit settings to match the Maya Working units.

Working with Feet and Inches

To change the grid into feet and inches while keeping Maya's default working units as centimeters

  1. Select Display > Grid > to open the Grid Options.
  2. Set Length and Width settings to 1.0 This represents the overall grid size.
  3. Set Grid Lines Every to 30.48. This is because 1 foot equals 30.48 centimeters.
  4. Set Subdivisions to 12. This divides the grid into 1-foot squares with a subdivision every 12 inches.
Large scenes
It is difficult to work at real world scale on a large scene (such as a city) in centimeters as you would be dealing with exceptionally large values, which could create precision errors.
In these cases, it can work to set the unit as a meter, while linear units are set to centimeters.
Character and scale
A general rule is that a character should be 10 units tall to avoid precision problems.
Animation and scale
As Maya internally uses 1 unit to represent 1 centimeter, this is often too small for a scene where an animated character covers a large distance. For this, try switching to 1 unit = 1 meter. Of course, switching units from 1 cm to 1 meter creates precision problems where your animation would be far from the origin in scenes that span great distances, but you can account for this if you animate your set around the actors and the camera instead.
Clipping planes
If you work at real-world scale at units of centimeters, you likely need to adjust your clipping planes. Check your orthographic camera positions as they may be situated too near to your objects. This needs to happen especially if you convert your scene to meters. See Clipping Planes.

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