Templates and donors
LDCad template and donor files are plain LDraw documents and therefore don't need additional format explanation. I would like to shine some light on their meaning and additional configuration options etc though.
LDCad template files are LDraw code snippets you can drag from the part bin into your models like any other part / model. For this to work LDCad maintains a special template folder which contains all the default ones. Also needed are part bin groups aware of these templates in order to make them appear inside the part bin.
You can add templates your self by adding a template location using the Prefs/LDraw menu followed by saving one or more LDraw files in it. Some guidelines are:
- Only single content (non MPD) LDraw files can be used as templates.
- Only supported LDraw line types are copied/inlined when using templates.
- Templates will only show up in the part bin if you set their header information in such away they match one or more of the default template group files. See the default templates for examples.
When you plan to create many templates yourself it might be needed to create custom part bin group (pbg) files for them. That way you can organize them more logically inside the part bin.
LDCad generated content template files
One major use of templates in the default LDCad configuration are the path and spring parts. These templates define a useful starting situation for e.g. a pneumatic hose or shock absorber.
You can create these kinds of templates your self by starting standalone path or spring files inside LDCad using the file/new... menu.
Donor files are special LDraw part (.dat) files to be used while generating path content.
When used in e.g. path content skin they will be searched for using the normal LDraw search locations. It is best to keep them separate for organizing purposes though. The default LDCad donors are located in the donors folder at the configuration location. This location will also be forced into the LDraw search locations list.
If you are designing custom path (flexible part) content you might need to also create a number of donor files. You can store such files anywhere you like even in existing LDraw library locations etc. But it is cleaner to give them a special folder somewhere and add that location to the search locations using the special 'donor' type in the LDraw search locations dialog accessible from the Prefs/LDraw menu.
Creating a donor file is identical to creating (un)official LDraw part/primitive files. Only extra issue you might want to worry about is where and if to include conditional lines when you intent to use them with the deform placement method. This because it might result in very large generated content files while not really worth it visually speaking.
Before creating custom donors it might be useful to browse through the official/default LDCad ones as I added some comments on them here and there.