The long awaited tech demo of Valve's flagship source engine powered Lost Coast was delivered via Steam last week, free to all legitimate Half Life 2 owners. Weighing in at around 66mb, the download was quick and painless over the cable connection.

For the benefit of gamers who have been living on Mars the past 6 years, Half Life 2 is the greatly anticipated sequel to Valve's 1998 game of the year, Half Life. Featuring exquisite graphics and physics, HL2 wiped the floor with every other game released around the same time last last year, even stealing thunder from id's Doom 3.

If you remember the tech videos Valve released prior to HL2's launch, they featured a new technology called HDR ( High Dynamic Range ) lighting. However when HL2 finally shipped the aforementioned technology was absent for reasons unknown, but was likely to maintain a greatly range of compatibility across several video cards.

Now Lost Coast is here in full HDR glory, and for what is a rare occurrence in the video game industry, the product matches the hype.

A High-Dynamic Range image has a contrast range far greater than can be shown on a typical display device. Scenes that were previously dull and flat now look vibrant. As you walk around the map and move in and out between indoor and outdoor scenes, the lighting effects are dynamically changed to imitate different levels of contrast and in particular to emulate how our eyes adjust to variations in lighting. For example, when you are outdoors in a brightly lit environment and walk indoors, your eyes take a little time to adjust to the sudden change. This effect is emulated in Lost Coast .

Aside from the lighting effects, Lost Coast uses the standard (stunning) HL2 engine. The addition of HDR lighting does make it look significantly better though; as if it needed it.

The Lost Coast level is disappointingly short at around 10 minutes of game play, although you can extend this to 15 minutes if you take the time to enjoy the scenery while under heavy Combine gunfire.

Additionally, the level can be played with commentary mode on. This displays several points throughout the level that can be accessed with providing commentary by lead designers and Valve head honcho Gabe Newell. The commentary basically explains how HDR lighting is rendered to each scene, and demonstrates using split screen comparisons.

Anyone interested to see the future of lighting in games should check out Lost Coast . If you thought HL2 was the ducks nuts of game engines, you will be even more impressed with the Lost Coast level.

Pros.

• Free to HL2 owner
• Small bandwidth footprint
• Amazing lighting effects
• It's more HL2!

Cons.

• Very short game play
• Buggy enemy positions after respawn
• High system requirements for smooth gameplay