1 reply to this topic

[Nick]

Hi all,

Current applications with dynamic HDR apply the same exposure factor to the whole screen. But our eyes actually adapt to the light in regions, and even per color component.

For instance when in a dark room and looking through a window to a bright outside your eyes will adapt to see both the room and the outside with good contrast. In current games either the room is clearly visible and the window is one white bloom, or the outside is clearly visible and the room is too dark to discern anything. In the real world you'll often see both, and when you turn away there's an afterimage of the window (appears as a dark spot). In illusions the afterimage effect is even used to produce inverted colors when looking away from the image.

So I was wondering whether this would be useful for games as well. We obviously want to see as much of the scene as possible, and don't want to be 'blinded' by HDR.

Thoughts?

Nicolas

[Reedbeta]

I know the offline rendering people have come up with a lot of sophisticated tone-mapping techniques to address exactly this problem - spatially-varying exposure filters and so forth. I don't know how well they would map onto a GPU but it's worth looking into. Some of these are described in Physically Based Rendering, by Pharr and Humphreys. I haven't got a copy of it here at work but I'll try to remember to post some more info when I get home.