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Usually one will want to bake to a separate image for each object. This can be done by encoding the Display filename with string “wildcards” that get substituted with actual filenames depending on Attributes on the objects. For example:

Display "<user:filename>.exr" "openexr" "rgb"

In this case, the wildcard <user:filename> is replaced by the corresponding user attribute specified for each object. For example:

Attribute "user" "string filename" "box1_global"

which then gets substituted into the Display filename. Alternatively, the filename can be specified with other attributes such as <identifier:name>. No image will be baked for an object if the wildcard substitution fails or if the filename for that object is the empty string.

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The resolution of the baked 2D images is determined by the standard Format description. For example:

Format 256 256 1

As an example, we’ll bake 2D textures of global illumination in a Cornell box with two spheres. The box consists of five squares, each with a separate texture. One of the two spheres is purely specular so we do not bake on that. Figure 2(left) shows the baked images for the five faces of the box and for the diffuse sphere.

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