We have lots of small BMP files which I think would be easier to copy if we had them combined in a big TAR/ZIP/whatever.
What is the state of the art at shipping game graphics?
We are using C# and are aware of zlib. Just brainstorming to see if there are any other solutions better than zlib.
You could also look into SharpZipLib or DotNetZip - DotNetZip gives you access to a Stream directly, which is helpful as most C# libraries out there can load from streams (as opposed to files). Furthermore DotNetZip uses the Ms-PL (BSD-Like), instead of the GPL with a legally questionable exception.
Another option is to use texture atlases - instead of having many small images have a few big ones. These actually load slightly faster and are slightly faster at runtime if you get smart with how you draw them.
Finally you could run each asset type through the relevant lossless compressor (PNG, FLAC, etc.) and store them in a flat file (basically a zip file with compression disabled). Remember to avoid compressing compressed data, as that will increase the size in most cases.
Some prior art:
An option is to store images in the same compression format that you use for making compressed textures. This has the advantage that you are not going to convert fro one lossy format to another, yet you store the data in a lossy format. Depending on the textures there may still be something to gain by storing such files in a compressed archive.
See this answer for a bit more info on compressed textures: https://gamedev.stackexchange.com/a/5177/3505
ZLIB could be a good answer, but if you're aware of people opening grabbing your assets, you could also make your own file format to store your assets, its not that hard though.
Here's how you can make it.
It is in C, but should not be that hard to learn, as C# is some like C and C++.
Of course, people that still have higher knowledge can catch your resources, you can add little encryption if you want, not too hard.
This can be very useful, but it will just join your files. For compression too, you have two choices.
Make your entire resources file, compress it, and ship.
This Method is easy, but not very good, you should uncompress everything if you want to take just one resource.
Compress every resource, and add they compressed to the resource file.
That's pretty good too, you'll have a slight increase in the size beside the method 1, because each file is compressed separately, but its better if you want flexibility.
Each method has its own drawbacks, you should choose wisely. Generally, if you game has a pretty low number of resources, method 1 should be better, If you have LOTS, the method 2 should fit you, because the size of all resources together will overwhelm the extra that you gain.
For compression libs, you have:
I would go with LZO if I want fast access ingame, so you have not to fear about uncompressing in real time, 7-Zip if I want the files to be shrinked A LOT or Zlib itself if I want balanced decompression ratio and size.
The choice is yours :D
Ah, of course there are others algorithms to compress data, and you can find those googling.
