From: Braden M. <br...@en...> - 2006-09-16 09:21:32
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The last release underscored for me once more what an annoying dependency Antlr is for this project. So I've been scratching my Spirit itch lately. I've finally figured out how to use Spirit's stored_rules effectively to make a self-modifying grammar. That probably sounds a bit more high-minded than it actually is; though it *is* pretty cool. Where in Antlr I had used a semantic predicate to resolve ambiguity in the grammar, the Spirit solution using stored_rules uses a semantic check to swap out the branch of the grammar at parse time such that there's never anything to disambiguate (at the grammar level). Nothing's checked in yet; but this work is probably about 70% done. The only construct I have left to parse is IS statements in PROTOs. And then I'll need to go about making it construct OpenVRML scenes. I'm planning on exposing this new parser such that users can use Just The Parser directly, supplying their own semantic actions. This should facilitate a more lightweight solution for users who just want to get data out of a VRML file. I have No Idea how this Spirit parser will perform relative to the existing Antlr one; but it will be interesting to see. I've also been inching forward with getting Text node rendering working on Windows. While I still don't have a good understanding of the Right way to convert a CSS-style font specification into an actual font on Windows, I am at the point where I can pick *something*. So I expect to be at a point where I'll have something worth putting into a 0.16.x release before too long. -- Braden McDaniel e-mail: <br...@en...> <http://endoframe.com> Jabber: <br...@ja...> |