Mask Map (Vehicle)

A mask map is a texture used for specifying a vehicle's window surfaces, headlights, and brakelights. SimCity 2013 uses this map to add glow effects to headlights and brakelights, and add a faked-perspective interior (through use of interior UVs) to a vehicle's windows.

Components of a Mask Map
A mask map has three distinct parts:
 * Window region
 * Headlight region
 * Brakelight region

These three components are used to add an extra level of detail to a 3D vehicle model. This map is similar to a color map in that it requires a UV mapped object to be applied to.

Window Region
A vehicle's windows are made up of a number of elements, each playing an important role in how the window is displayed; geometry, interior uv coordinates, interior texture,  color map and mask map.

Windows are first defined with an object's geometry. This is the physical surface on which the window will appear. Interior UV coordinates are then added to those polygons, mapping the interior texture onto the surface. The window is cropped with the mask map window region, which defines the perimeter of the glass pane. The color map is used underneath the mask map for any leftover transparency with the window region.

See also: Interior UV Coordinates

Headlight Region
Headlight regions are defined by a specific colored pixel:







Headlight glow is visible on vehicles during nighttime hours. The lights are active anytime the vehicle is on a roadway. The larger the defined area, the brighter the headlight's glow effect becomes.

Brakelight Area
Brakelight regions are defined by a specific colored pixel:







Brakelight glow is visible on vehicles during all hours of the day. Brakelights are active anytime the vehicle is on a roadway, and get significantly brighter when a vehicle is slowing down or approaching an intersection to turn. The larger the defined area, the brighter the brakelight's glow effect becomes.