Valve Source Engine Update: Filmic Effects
Recently, Valve Software invited a handful of hardware editors to their offices in Seattle to showcase some upcoming changes to the Source Engine including developmental graphics technologies that Valve hopes to release in a future version of the software in the next year. The list of changes and features isn't very long since software development takes a long time, especially when we are talking about the company's reputation for making cutting-edge graphics and games. Having just recently added HDR (high dynamic range) imaging to the engine with the Lost Coast demo and Day of Defeat: Source, what could they have up their sleeve now?
This new round of imaging enhancements continues down the path that HDR started on in the gaming world: implied complexity. Implied complexity is a contrast to explicit complexity that has been the focus of the 3D world since its inception. Explicit complexity includes things like increasing the polygon count of an object to make it (and the corresponding curves) it appear more life-like and adding higher and higher resolution textures to those polygons to add details. All of these and other explicit complexities work well, but at the cost of a huge demand for faster and more powerful hardware. If you could make HL2 look better by doubling the polygon count and texture resolutions, chances are the current generation of hardware would have trouble keeping up. This is in fact why the GPU arms-race has been so important to leading edge software developers; the hardware is enabling them to create more explicit complexity.
Video Link - The Entire Demo Movie (~ 200 MB)
Implicit complexity is the idea of actually distorting the rendered image in a way that essentially reduces the sharpness and fidelity of the image, but actually improve overall image quality by giving the perception that the image has become more complex. Some of these implied complexities that Valve discussed with us included motion blur, depth of field, color correction and film grain. The latter two, color correction and film grain are possible in real time with today's hardware and will be implemented in the Source engine soon, so we'll look at those two first in our discussion. Both motion blur and depth of field are still a ways off from real time (especially in the current implementations that Valve coded) but they hope to have them running by next year. We'll go into detail on them as well following this section.
Page 2 - Color Correction