Tutorial
Here's the video of the scene, loaded in CS 1.6
GoldSrc Sci-Fi| Modeling of high quality sci-fi scenes in Valve's original version of the GoldSrc engine, pushing it to its limits.
Larger number of 512xX textures were used and every texture is scaled down to 0.5x0.5, thus what you see is probably near the limit of what GoldSrc can handle.
Posted by Gojkovic on - Advanced Level Design/Theory
Loving the texture work.