Talk:Texture Cache

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Revision as of 02:30, 24 March 2007 by Iron Perth (talk | contribs)
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We can safely avoid the GIF format. It's 256 colors only. it use unisys patent LZW (the good old patent used in the good old GIF expired, but unisys repatent'd it because of some "improvments" in the algorithm.). Unisys suddenly claimed they wanted royalties to encode GIF file, and just for that we shouldn't use it. source : License Information on GIF and Other LZW-based Technologies -- kerunix Flan

The last of the patents expired in October 2006. GIF is no longer patent encumbered. But PNG is still better. Keep in mind by recompressing the image to cache it you're trading CPU usage for disk space. Compression is usually a lot slower than decompression. Just storing uncompressed might be overall faster. In the end, we need to assume nothing and benchmark, benchmark, benchmark. Seg Baphomet 22:45, 23 March 2007 (PDT)

Databases

There appears to be support with APR for a portable interface to common databases, namely Berkely-DB and SQL. Dzonatas Sol 18:23, 23 March 2007 (PDT)

Stats

It would be useful to get stats on current and new hardware profiles from LL to get a sense of what people are using and where the focus should lie.—The preceding unsigned comment was added by Iron Perth

TGA

I can't find it in the spec, but i think this format give the warranty that images of a given size will always have the same file size. (without RLE of course). This may help for some optimization.

Additionaly, the "developper area" of the TGA file format could be used to store some usefull information.—The preceding unsigned comment was added by kerunix Flan

Converting images into the TGA format for cache storage has the advantage that the client already supports rendering TGA images. It would be one of the easiest solutions. Images with the same dimensions would all be the same but otherwise would be different in size. Strife Onizuka 02:22, 24 March 2007 (PDT)


Faster Formats

Contribution from Tofu Linden from the email discussion

RLE is cheap but also not very effective at all for many, many textures; wherever I might have used RLE in ye olden days I'd now use trusty old zlib or blingy liblzf, the latter of which is more or less on the same order of speed as RLE but a LOT more effective on data (images) with redundancy not necessarily manifesting as runs of pixels.

Iron Perth 02:30, 24 March 2007 (PDT)