Zugg Software :: View topic - Changing mapper "shapes" from WMF to SVG in the future

Posted: Fri Dec 12, 2008 12:31 am

One of the areas that will get a lot of improvement in the new mapper early next year is the graphics rendering engine.

Currently, the mapper in CMUD (and zMUD) uses the "Windows Metafile" (WMF) format for creating custom room shapes. The raw Windows GDI library is used for the graphics rendering. This causes many limitations in the current mapper. For example, line styles are severely limited in the Windows GDI. No anti-alias support, no gradient support, etc, etc.

The new mapper will be using a new graphics engine early next year during the Phase 2 of the new mapper rewrite. Instead of using WMF for shapes, it will use "Scalable Vector Graphics" (SVG) format. SVG is an industry standard vector graphics format based on an XML structure. SVG files can be directly rendered in all web browsers except Internet Explorer. As a text-based graphics format, you will be able to create/edit custom room shapes directly from a text editor instead of requiring the use of a GUI editor (a GUI editor will be available in cMapper).

In selecting the backend graphics library, I am looking at both Cairo and Anti-Grain Geometry (AGG). I have found Delphi bindings for both libraries. The Cairo system would require several external DLLs, while the AGG library could be compiled directly into the CMUD EXE. So I'm leaning towards AGG right now.

Both libraries will provide significantly more functionality for the mapper graphics compared to the current Windows GDI implementation. You can expect to see support for anti-aliasing, font scaling, gradients, line styles, curved exit links, and much much more.

cMapper will provide a full GUI interface for editing maps, creating and editing SVG shapes, bitmaps, etc. The current WMF shape editor in zMapper will not exist in cMapper, but both cMapper and CMUD should be able to convert existing WMF custom room shapes into their SVG format.

I'm announcing this now to provide time for feedback. If you have any experience with either Cairo or AGG, please post and let me know about it.

Wizard Joined: 14 Oct 2000 Posts: 1368

You might want to be careful with AGC. It looks like it might be GPL, http://www.antigrain.com/license/index.html. Pretty annoying with such libraries in my opinion.

Posted: Fri Dec 12, 2008 8:47 pm

No, it's fine. The AGG v2.4 that I'm using still has the proper license that is free for commercial use. It's only the newer v2.5 that has the GPL license. I agree that this is annoying and it's going to push more people towards using Cairo instead. And it definitely something I'm thinking about since it would prevent me from updating to newer versions. But the Delphi wrapper for AGG is only for v2.4, so I'm fine for now.

Magician Joined: 17 Apr 2005 Posts: 496

Hey! This is what I wanted that you shot down a while back. Awesome.