Not all of Left 4 Dead's visual effects are as apparent as the above comparison between an early-version screenshot and the subsequent final build screenshot of the same alley. Just the same, you'd be surprised at the amount of innovative detail that was put into Left 4 Dead's dynamic lighting alone.
Randy Lundeen discusses lighting and its in-game effects via the official Left 4 Dead blog. The post includes screenshots like the two that I cannibalized, as well as video clips and a lot of nifty information that gives you a window into the development of our 2008 Co-Op Game of the Year.
What are you waiting for? The snippets? Well, too bad: you'll have to read this one for yourself. Click here or at the source link below.
Source: L4d.com