How do I validate what schema my Collada file is in? What/how many collada schemas are there? How do I change the schema of a Collada file (for example from 1.5 to 1.4)?
COLLADA documents are XML documents so to validate them you simply have to open the document using a XML viewers or editors that support validation using XML Schema language (e.g. Dev Studio, XMLSPY, Liquid XML). On most Linux and Mac OSX systems, you can run xmllint from a terminal window to validate XML documents. Some COLLADA specific tools include XML validation using the capabilities of XML libraries like libxml2, MSXML, and xerces.
There are three COLLADA schema (1.3, 1.4, 1.5) although only two of them are actively supported by Khronos and most developers (1.4 and 1.5). You can find them at their hosted name spaces here:
You can’t simply change the schema of an existing document as that would invalidate the document since its contents would not match a different schema.