After many time messing with the source engine, I started to improve my knowledge towards texturing and modelling. Specifically texturing and material editing and setting up,which made me use VTFEdit a lot. By that time I learned many things about it and which you may want to read about.
VTFEdit's General Options are:
- Normal Format: By default this is leaved as DXT1 which is a great choice by itself. Many chooses this format because it compresses the texture without it losing many quality and having a good size in the end.
If the texture is way too big and you're having problems when importing a big texture plus you want it to be the best looking possible, you should try selecting BGR888 instead of DXT1. It will also make the texture load way more faster.
- Alpha Format: This is important for textures that has a alpha channel over them (aka pngs), you should have in mind that you need to leave the DXT Compression (in advanced options) always at high if you want it the alpha be in good quality. The best quality that you can get of a alpha-texture is if you choose ABGR8888 instead of DXT5. It will remove the compress feature,will make the texture load faster but it will make the texture size be way too high.
- Mipmaps (Generate Mipmaps): Mipmapping is essential if you want your texture to be optimized and have low-res support for players that are used to play the game at the lowest quality possible. If you don't enable it your texture won't have any level of detail (LOD), it will make the texture load even more faster but it will be the texture be super-sharp when seen from a distance. You should not disable it.
- Mipmap Filter is a important option that you should set-up,the best filter that I have used is Kaiser, which still keeping the texture sharp and good from a distance. The most basic, simple and default filter is Box, it's also a okay filter if you texture have a standard 1024 texture size or lower,but may be un-acceptable for textures that are way too detailed or that have a higher resolution, Kaiser is the best choice for the mipmapping filter.
- Advanced Options: The first option which is Version doesn't has many differences when choosing a version. I mostly stick with 7.3 because the most newer ones are incompatible with older versions of the source engine. 7.4 & 7.5 seems to belong to the CS:GO source engine version.
- DXT Compression: This is quite important and you should note that if you texture doesn't has any alpha/transparency, you can put this to Low. You won't have any problems and it will even make you texture load faster,the size won't be affected though. Now if you do have a texture with a alpha channel you have to set it to High. Medium's not that of a good choice either, it will be also depending of the texture.
I hope that these hints may have helped you out, it's a pretty basic tutorial,I also have focused mostly on the important stuff.