Map Upgrade

A closer look on texture packages and the recent map upgrade process.

Shared texture packages

They have arrived! Alpha 27 ships a total of seven compressed texture sets that are ready for mappers to use.

As the name suggests, the textures are shared among the maps, without one map depending on the other. While this alone already reduces the net download size of an Unvanquished installation as maps don’t need to ship duplicates of these textures, the biggest improvment is in the compression itself. With regards to file size, the compressed packages are much smaller than the zip-compressed source format sets. While the latter are 335 MB total, the compressed sets total up to 115 MB, barely more than a third.

The second big advantage of the compression is greatly reduced map load time. We spent a lot of time during the map load process decoding the different texture formats. This part is now almost completely gone since the new format can be loaded directly onto the GPU. Reduced memory usage might be a side effect that was also observed when we compressed the game’s base assets.

Performance aside, I hope that mappers will have a quicker start given that they don’t need to download and cleanup the individual texture sets or write shaders and readme file entries for them. Last but not least, I have found that compressed textures unexpectedly look quite a bit better since the effect of normal mapping is more strongly defined.

New common shader set

Technically just another texture set, this package replaces the old common shaders that may have been in fluctuation before some of our mappers were born. A lot of cleanup and bug-fixing work has been done and, if you are a level designer, you might also enjoy a fresh set of radiant preview images for caulk, clip and friends.

Gamma reset

We have been using a default gamma value of 1.3 so far. This was a very bad decision because, obviously, mappers didn’t want their maps to look washed out and thus adjusted to the new setting, not only making it useless in the first place but also reducing the resolution of the brightness distribution as well as the player’s clearance for further gamma adjustments (artifacts show up sooner). We corrected this with the release of Alpha 27 by resetting the default value of r_gamma to 1.0. In addition, we also reset r_specularScale to 1.0. This means that all our maps had to be recompiled with new settings. However, we didn’t touch placeholder maps inherited from Tremulous yet and some of the old maps might appear too dark as a result.

Perseus

20140505-perseus

The prison complex found a layout update in addition to the switch to texture packages. Most notably, a new potential base location was added right behind the humans’ default base and the alien base doesn’t suffer from the vent access any more. I’m looking forward to testing the new layout in the next wave of public development games (each Sunday, 20:00 UTC on the Dev Server)!

Plat23

20140505-plat23

Platform 23 uses texture packages, has improved visually and features a small new area in the middle of the tunnel, which hopefully adds as much gameplay depth as the bunker below the platform. The map is also pending excessive testing during the development matches.

Other maps

While Parpax and Yocto have been put through the whole upgrade process, Chasm was recompiled to match the new brightness settings and will make use of the texture packages in a later release while Thunder has yet to be recompiled. Most of our maps, including the Tremulous maps which we use, use the new texture format by now.