Tuesday 29 June 2010

Compounding a problem (child object counts)

Compounds, the Herat map contains approx 500 of them. Each one consisted of a number of walls and out buildings. Turns out, these sub objects chewed through a bit of processing time. In effect there were 7500 objects getting worked through. That's a lot and it was reflected in the performance in LE 2.31 on a fully dressed map.

By collapsing the compound models into a single object for the lower LODs we saw a large increase in fps in LE 2.31. Although LE 2.32 shows not much difference (it's a better performer anyway) due to it's quad-tree culling system. Even so there lots of fine tuning to do, cockpit switches to be instanced, general code trimming. Entity view ranges, material combining and a dynamic detail function to add.

Today I've been working on fixing the lighting buffer for the cockpit entity but I'm having problems copying the cockpit buffer into the main view buffer. Much strangeness, it's some alpha/blending issue I can't quite get a handle on but I'll get there.

I spent some time looking at Open-flight as a specification for storing lots of scene data. It's not really designed for high efficiency 3D engines. And not surprising that other engines that use it have adopted some conversion process. Initially the idea was sound but on closer inspection it's just plain awful. Maybe I'm missing something in the organisation and construction of individual objects.


Here are some random shots from today.

Cockpit interior now moved to it's own world for rendering lighting. Materials are not happy but it's steady as a rock. You can see the GPU terrain mesh with it's 10 meter resolution rendering a DEM of mountains in the NW of Afghanistan.


Not much to say about this. Pre optimisation and post debug slowdown. Not happy at all. It was just this slow on my dev machine. My laptop is much happier.


The saturation and contrast levels adjusted on the "fly" can change the look of the game.


I like heavily saturated games which is probably due to my first colour computer, a Sinclair ZX Spectrum which was a train-crash of colours, all eight of them. I still have one of the later models hanging around my desk (see photo I just took below). This one has an Interface 1 for Microdrives. If you don't know what they were, have a bit of fun and look them up. Strange to think that that kind of technology is still used as a backup system today. In the 80's my first games didn't get very good reviews, we had a laugh looking them up on the internet last week. They would make good mobile games today I think....hey I just found my keys.

5 comments:

  1. Well done. Looking really stunning. I also like over-staurated colors. But I think its realistic when its about direct sun reflecting on sand surface. You can almost feel the heat. :-) Ohhh and ZX Spectrum. My first comp. I was 5, when dad brought this home. First brick wall destroyer game!!! :-D Today, I still play ZX Spectrum games. Visit - www.zxspectrum.net Awesome site!

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  2. Those were the days.

    If you've not seen "Micro Men", it's a film length BBC drama about Clive Sinclair and Chris Curry (former Sinclair employee who started Acorn Computers). Covers the birth and death of the home computer market at that time. You can probably torrent it somewhere, it's often on BBCs iPlayer.

    Also features a line from poet Robert Browning, "A man's reach should exceed his grasp, or what's a heaven for?"

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  3. :-) I will check it out. Thank You. A few days ago, I tried Tomahawk "simulator" after.........20 years? :-) Still awesome. I like its TADS :-DDD

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  4. I did try it recently as it happens when Dave and I were comparing old games we liked.

    He said it was a two colour flag simulator. Meanie. Except it's a spot on description.

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  5. Just amazing, what they were capable to create on such limited hardware. When You mention colour and ZX Spectrum, I think about F-19. When You were "feet dry", whole screen was green/yellow and when You went "feet wet", it switched to fullscreen blue. :-D Great times of transparent models. :-)

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