3D Data files are the standard file type for Creo Elements/Direct Modeling. Files are saved for each assembly, part, workplane, and workplane set. You can load these files at any level, which means you can load only the part of the assembly that you want to work with.
Instance and contents files
An instance file is typically saved for the top-level object, and contains information assigned to the object and a reference to its corresponding contents file.
An instance file is saved for each assembly, part, workplane, and workplane set. This file is named with the element's name in the structure browser. Each file contains the following information:
• For parts: attributes and properties like name, color, density, and position.
• For assemblies: names and position.
• For workplanes: attributes and properties like name, colors, and position.
• For workplane sets: names and position.
A contents file contains information assigned to the element. Its name is determined by the model name, if you have one assigned. Otherwise, the contents file has the same name as the instance file. These files contain the following information:
• For faces and edges: geometry and topology information, including face color, transparency, and part base properties.
• For workplanes: any geometry in the workplane and its colors.
You will not be able to reload an assembly file if you delete or rename one of its part files outside of Creo Elements/Direct Modeling.
Top-level instance files
When you save 3D data, you can choose whether or not to save top-level instance files. This option is found at the top of the Save 3D Data dialog (click Options in the Save dialog to open it).
If you leave this option on (the default), all objects at the top level (under root in the Structure Browser, denoted by a slash /) are saved in separate instance and contents files. Instance information is preserved for these objects.
If your turn this option off, instance files are not written and only contents files are created. The instance information of objects not at the top level (for example, parts contained in an assembly) is stored in the contents file of the object above it in the structure.
Although fewer files are written when you turn this option off, instance information of top-level objects is not saved, such as,
• Instance name and position of all objects.
• Color and density of parts (the base color and density will remain unchanged).
• Front, back, colors, profiles and construction geometry of workplanes.
When you load an object that has no top-level instance file saved, the base properties are displayed.
You can change the default setting is in the environment file.
