Weekly update, week 40 blog - bjorn98009_91

Time for my weekly update.

This week we've continued to make progress on our branding and now we've got the launch trailer and the entire soundtrack uploaded to YouTube awaiting unveiling. We've also made significant progress in the bug department, and right now we only have two maps that's bugging, none of them very severely.

The maps with issues are 06_HongKong_Helibase and 15_Area51_Final. The problem with Helibase have for a long time been a long standing occlusion issue. This is because in Unreal Engine 1 geometry occludes itself, that is the engine checks if the polygon is in view and if not it doesn't draw the polygon (to save time). The problem with that is that the code that checks if it's in view is not 100% accurate (if it was it would take too long to run and it would defeat the purpose of the check), thus sometimes at the edge of the screen the engine thinks a polygon is out of view when in fact it isn't and you can still see a part of it.

When geometry is built the polygons are cut up in a number of pieces and it's these cuts that the bounds checking code checks. With an unlucky collection of cuts this can result in many polygons flickering out of view and sometimes not just of the edge of the screen but a bit further in as well.

The issue then becomes how to affect how the level is cut up, and there are a number of different tricks one can do. It's a lot of trial and error and one change somewhere in the level can affect how cuts travel across the level and thus issues can either appear or disappear with one change. This of course requires extensive re-testing, even though I as a developer can check the target area to see if it works or not; other issues might have appeared elsewhere and I can't re-test the entire map each time I think it's good. I’m just glad that we still have a tester that is able to very rapidly and thoroughly work through this.

Earlier today I discovered another non-occlusion related issue in Helibase, hopefully I'll be able to fix that soon, but as always one change can undermine the fix for the occlusion issue I worked on before. In Final we have a similar occlusion issue, however this map also have a few other non-occlusion issues as well.

Progress for me has been impeded slightly due to an exam tomorrow, but tomorrow evening I should be able to get on this and try and sort the issues out.