3ds Max 2012 Bible - Kelly L. Murdock [365]
FIGURE 34.2
The General Settings rollout of the Render to Textures panel includes settings for all objects.
To create a baked texture, select a Texture Element from the Output rollout and click the Render button. Clicking the Render button creates the baked texture for the selected object and saves it in the directory specified in the General Settings rollout. It also applies an Automatic Flatten UVs modifier to the Modifier Stack and applies a Shell material to the object. The Shell material contains the object's original material along with the new baked material. You can select which material is displayed in the viewport and which is rendered using the options to the bottom right of the Render to Texture dialog box.
Note
You also can select Use an Existing Channel for mapping coordinates. This is a good choice because the Auto Unwrap option doesn't have the control over the UV coordinates that you may want, and sometimes it does a poor job of unwrapping the mesh. •
The interface also includes an Unwrap Only button. This button can be used to flatten the UVW Coordinates for the selected objects and to automatically create a map channel.
General Settings
The General Settings rollout includes an output path where the baked texture is saved. The file is saved by default using the Targa file format. The Skip Existing Files option renders only those elements that don't already exist in the designated directory. The Rendered Frame Window option displays the resulting map in the Rendered Frame Window along with saving the image as a file. For the render pass, you can select which rendering settings to use, including the mental ray rendering engine. The Setup button opens the Render Scene panel, where you can change the render settings.
Selecting objects to bake
In the Objects to Bake rollout, shown in Figure 34.3, a list displays exactly which objects, subobjects, and channels will be included in the rendered texture. The Padding value defines the overlap in pixels of the texture. The Objects to Bake rollout also includes a Presets list that lets you save and reload defined settings.
FIGURE 34.3
The Objects to Bake rollout of the Render to Textures panel lets you specify which objects are baked into the texture map.
The Projection Mapping section lets you enable the creation of a normal map using a Projection modifier. These settings are covered in detail in the “Creating Normal Maps” section that appears later in this chapter.
The Mapping Coordinates section lets you choose to use the mapping coordinates of the Object or the Subobject selection contained within a specified channel, or you can select to use the Use Automatic Unwrap feature, which automatically flattens the mapping coordinates. If the Use Automatic Unwrap option is selected, you can set the mapping options in the Automatic Mapping rollout. By default, unwrap mapping uses channel 3, but you can change this channel if you wish. If a different mapping uses channel 3 and you don't change this, the new mapping replaces the old one. The Clear Unwrappers button removes any existing Unwrap UVW modifiers from the object's stack.
You can select to bake an Individual object, All Selected objects, or All Prepared objects, which are all objects with at least one texture element.
Output settings
The Output rollout, shown in Figure 34.4, lists the texture elements that are included in the texture map. The Enable option can be used to disable the selected texture element, or elements can be deleted with the Delete button.
FIGURE 34.4
The Output rollout of the Render to Textures panel lets you choose which texture elements are baked.
Clicking the Add button lets you select the type of texture elements that you can render. You'll want to use different maps depending on the purpose of the map, and you may want to render several at a time. The available types are CompleteMap, SpecularMap, DiffuseMap,