Custom Levels and Model Skins

Tuesday, 24th July 2007

An XNA Quake implementation the way I intend on working - that is, to start from scratch - is not really worth it (as far as getting the gameplay 100% identical to DOS Quake).

As a learning project, there's a decent quantity of further material (as far as maps, high-resolution textures and so on go), and I intend on trying to learn how to write a 'FPS-friendly' 3D engine based around Quake's data. Whether I shoehorn some sort of game into that or not is yet to be decided.

Anyhow, I mentioned that I'd be moving on to light maps. Unfortunately the documentation I have is rather vague on this topic (the Unofficial Quake Specs), and I can't get meaningful data out of the BSP files.

I had a slight issue to resolve. Certain textures were appearing as a single colour, like the above. As far as I know this is a symptom of using crazy texture coordinates. I wrote a crude routine that attempts to shunt vertices into the 0..1 range, and the result looks a bit better:

As you can see, the top edge of the large texture is still badly distorted.

I modified the resource loader slightly to handle loading files outside the main pack files.

The result is that I can low load resource files - such as external levels - as you would any other resource, with a call to LoadResource<Data.Level>("maps/ikspq5.bsp"). The level loader also parses the entity declaration block inside the .bsp, putting the player in the correct starting place and - more noticably in the screenshots - finding out the title of the level.

I've made a start at loading the Alias .mdl files, but their structure is rather convoluted so the only visible result thus far is a dump of all of the skin pictures.

There doesn't seem to be much information about Quake BSPs (plenty on Quake 3 BSPs, however!) so if anyone has any recommendations I'd be grateful. Looking at flipcode's article on Quake 2 BSPs it would appear that they're not too different, so I'll have a go with that.