Support for Civilization for Windows sounds

[SWY1985]

Because it's going to take some time to figure out how to decode the original Civilization for DOS sound files, it's a good idea to add support for the Civilization for Windows sound files. If the .wav files exist, CivOne will play them. Otherwise it will just run with no sounds.

[SWY1985]

In order to play the game with CivWin sounds, you'll need to copy all the .wav files from the original (Civilization for Windows) folder to ~/sounds/** Also, you need to install OpenAL: https://www.openal.org/downloads/

This feature is experimental, and basically a workaround until we manage to discover how the original Civilization for DOS sound files work. It adds a bit of life to the original game.

Please, do not post links to the original sound files. If someone does not own CivWin, they'll have to live without sounds for the moment. Sorry...

[SWY1985]

This feature has not been implemented in the SDL version of Civilization. I also want to add a GUI for adding the files, instead of manually copying them.

[SWY1985]

Now that support for playing sounds has been implemented in the SDL runtime of CivOne, here's the todo list:

• Add a setting in the Setup screen to add the WAV files
• Use all (relevant) sound files

The following sound files are not yet used:

• AIRNUKE.WAV (when using a nuke on a city) (done)
• CANNON.WAV (when attacking with a canon) (done)
• LOSE2.WAV (when losing a game) (done)
• S_LAND.WAV (when attacking with modern weapon units) (done)
• S_NUKE.WAV (when using a nuke outside a city) (done)
• WINTUNE.WAV (when winning a game) (done)

[SWY1985]

All CivWin sounds are now used. Now we just need a setting in the setup screen to add sound files.