Compression and dicing don't mix well

[Jimadybobalon]

Hey,

I need to compress my sprite sheets down a lot, at the moment. But every time I do, regardless of the compression type I choose, I get lines along all the dicing lines, on every sprite. Is there any way I can get rid of the compression lines without having to undice the sprites, as I don't think I can fit them all in without the dicing. Less dicing may be an option, but that'll just result in less lines (there are a LOT). Am I doing something wrong, maybe?

Thanks~

[unikronsoftware]

no, you're not doing anything wrong. it is more or less expecte dthat you're going to get terrible artifacts with dicing and compression. How bad depends very much on the platform you're targetting - eg. DXT on PC is gonig to look quite different to PVRTC on iOS. Not much you can do apart from trying to increase the padding on the textures, but then you'll be trading texture space for quality. Texture compression assumes a contiguous image, and works best with it.

Imagine heavily JPEGing a large image, and then shuffling the image as dicing does, and then JPEGing, and finally restoring the original image. The result of the latter is going to look far more offensive than the first.

[Jimadybobalon]

Damn. So I'm gonna have to compromise on something then.

Well Extra Padding 4 seems to have made it A LOT better. Fucking about with values at the moment. Is there any method of deciding the correct amount of padding necessary from other info of the image and dicing? Or shall I just keep fiddling until it looks the best? Also what's the method on deciding the correct amount of dicing for sprites? I've generally just been setting all of my to 64x64 :\

[unikronsoftware]

The amount of padding very much depends on the platform. The correct amount of dicing for sprites is the largest you can get away with. If your sprites has a lot of empty 0 alpha transparency in it, you'll get better results & savings with smaller dicing. If its fully solid you will probably do better with larger dices.