Given a low resolution object and a high resolution source object/group (two versions of the same character, for example), the Ultimapper tool bakes the normals, surface color, and other attributes of the high resolution source object/group into maps that can be applied to the low-resolution destination object.
The high resolution source can either be a single object or a group of objects, while the low-resolution destination must be a single object. Note, however, that you can apply the Ultimapper property to as many low-resolution objects as you wish.
When you apply this property to a low-resolution object for the first time, a number of things are automatically done:
The tool requires a texture projection (UV set) on the low resolution model. If no projection exists, the tool automatically creates a new texture projection. If one or more projections exist, the first one created is automatically used.
The tool requires a Color at Vertices (CAV) property to store tangents. If none exists, the tool automatically creates a new CAV property. If one or more CAV properties exist, the first one created is automatically used to store the Tangents.
For a complete procedure, see Transferring Surface Attributes (Ultimapper) [Texturing].
To apply: Select a low-resolution object and choose Get 
Property Ultimapper from any toolbar.
To redisplay: In an explorer, expand the low-resolution object and click the Ultimapper icon.
| Path |
Specifies the output path for all of the maps activated on this tab. Type the path in the text box or click the More button (...) to browse for the path. |
| Prefix |
Specifies the prefix, if any, that is added to the file name of each generated map. |
| Type |
Specifies the file format for all of the generated maps. Available file formats are: |
| Available Maps |
All of the available maps are listed. Each map has a check box that you can use to toggle whether the map is generated, and a text box where you can enter the map's file name. Activate any combination of the following maps: Normal in Tangent Space/Normal in Model Space: Normal maps are a color representation of the object's surface normals' directions. Each color component represents an axis. The Ultimapper tool uses the normal map, in conjunction with a tangent map stored in a Color at Vertices property, to simulate high levels of surface detail on the low-resolution destination object. You can generate a normal map computed in tangent space, object space, or both. Bent Normal in Tangent Space: This is the average direction of the unoccluded sample rays cast when calculating ambient occlusion. They are stored in tangent space. Albedo: An albedo map is simply an image representing the object's surface color without considering illumination. Depth: Depth maps, also called height maps, are grayscale representations of the height of every point on an object's surface. The Ultimapper tool uses height maps to create a more realistic bump-mapping effect called parallax mapping, which simulates the correct displacement you perceive on an object's surface based on the camera's point of view. Ambient Occlusion: Ambient occlusion maps use the Ambient Occlusion shader to create a color representation of the extent to which the object is occluded by other objects, or the environment, at any given point. The more the object is occluded, the greater the effect on its ambient illumination component. When you're setting the Ultimapper properties, you can use the options on the Advanced tab to adjust a subset of the ambient occlusion shader's parameters, which control the final output map. Material Tags: A material tags map is a simple color representation of where different materials are applied to the high-resolution source object used by the Ultimapper tool. This type of map is not used directly for texturing, but can be quite useful when editing texture maps. For example, in a 2D image-editing program, you could use it in a layer as a selection guide. This allows you to select a single material's coverage area and then edit that area in a different layer. |
| Uvs/Tangents |
The low-resolution object's texture projection (UVs) and CAV property (for storing Tangents) are set automatically. In cases where the object has multiple UV sets or CAV properties, you can click the appropriate Pick button to begin a pick session, choose a different UV set or CAV property, and right-click to end the pick session and update the tool. You should have an explorer open before starting the pick session, since you'll need to expand the object's hierarchy to access its texture projections and CAV properties. |
| Keep Tangent Operator |
Controls whether the tangent map (stored in the CAV property) is kept after you generate the other maps. Deactivating this option makes the tangent map uneditable. |
| Freeze Tangents |
Bakes the tangent map into the object. Note that the resulting tangent map is not editable. |
| Adjust Tangents |
Allows you to adjust the tangent map. See Tangent Operator (TangentOp2) Property Editor. |
| Number of Samples |
Specifies the number of sample rays used to determine occlusion. Higher settings produce a smoother result but take longer to render. If set to 0 or a negative value then mental ray will use the global Ambient Occlusion > Rays setting in the mental ray Render Options Property Editor. |
| Bright Color |
This color is used to scale the ambient lighting/reflection when the sampled point is completely unoccluded. If the point is partially occluded, this color is mixed with the Dark Color. Typically, this color is set to white, but you can choose any color using the sliders. You can also drive the color using a texture. |
| Dark Color |
This color is used to scale the ambient lighting/reflection when the sampled point is completely occluded. If the point is partially occluded, this color is mixed with the Bright Color. Typically, this color is set to black, but you can choose any color using the sliders. You can also drive the color using a texture. |
| Spread |
Defines the angle of the cone from which sample rays are fired. A value of 0 samples only in the direction of the surface normal, while a value of 1.0 samples the entire hemisphere above the sampled point. |
| Maximum Distance |
Specifies the maximum range for sample rays fired from a given point.
It's usually preferable to limit the maximum distance by using non-zero values. Distant objects generally affect the final result less because they occupy a proportionally much smaller area of the sampling hemisphere than closer objects of the same size. The slight reduction in overall occlusion that this may cause is offset by the accompanying reduction in render time. |
| Reflective |
When activated, the shader performs reflection occlusion rather than ambient occlusion. This changes the sampling pattern from a cone around the surface normal to a more distributed pattern around the direction of reflection. Using reflection occlusion can help enhance the realism of reflection maps by incorporating color and detail from the surrounding environment map. |
| Output Mode |
The shader had five different modes that control the output color:
|
| Occlusion in Alpha |
When activated, the scalar occlusion value is stored in the alpha channel, irrespective of the specified Output Mode. Normally, the color returned for a given point is a blend between the Bright color and the Dark color, including the alpha channel, depending on how that point on the surface is occluded. When this parameter is on, the blending between the bright and dark color is not done for the alpha channel. Instead, the alpha channel stores the actual amount of occlusion. If you need the alpha channel to be 1, independently of the occlusion, simply set the Bright color and Dark color alpha values to 1, and the blend will always return 1. |
Except where otherwise noted, this work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
