On 09-Dec-2002, Stephen J Baker wrote: > On Fri, 29 Nov 2002, Sam Richards wrote: > > > I would like to stress that some of the film-industry interest in > > filmgimp is as much for the floating point as the 16 bit. The need for > > floating point is for "High Dynamic Range" imagery which is used as a > > lighting tool, and not for final delivery. So while I can believe that > > many films can sucessfully be rendered in 8-bit, its quite possible that > > at least some of those films will be using HDR imagery, so there will be > > a need for a paint system that can help touch up these images. > > Notice that the latest series of graphics cards from nVidia and ATI > (and others) support floating point all the way through to the frame > buffer. This will mean that the 3D rendering community (games, simulation, > etc) will be very interested in floating point image processing and > storage in the very near future. > > I would urge everyone to consider floating point pixels rather than > just going to 16 bit. This is a big change and you only want to make > it once. Erm, thats kinda cool, but unless we can access that framebuffer, it wont be useful to us. We'll still be stuck writing to the 8bit per channel 2D framebuffer. (Now, of course, we could chop the final display image into GL texturers, and display that, but that requires a spfp per channel GL texture mode.) Ive been asking for spfp per channel rendering for a totally different reason: not only can you have numbers above pure white (> 1.0) and below pure black (< 0.0), but you can properly use SSE to accelerate FP calculations (using gcc 3.2.x and up with -msse and -mfpu=sse,387. On my Intel P3, apps that heavly used spfp math had a speed increase of 2x-4x, all due to the extra execution units chugging along.) This also helps with HDR too. HDR is a spfp per channel storage mode, used by several high end industry apps. Those included is Lightwave, the famous 3D modeling/rendering application. With HDR enabled (and saving in a HDR format), you can alter the final image to bring out more detail from shadows and such by just altering the gama ramp, Due to the huge ammount of data, you wouldnt notice the difference the "fixed" copy, and the entire image rerendered with new lighting settings to correct the "mistake:" the least significant bit of data is still below even 16-bit per channel display modes. -- Patrick "Diablo-D3" McFarland || unknown@xxxxxxxxx "Computer games don't affect kids; I mean if Pac-Man affected us as kids, we'd all be running around in darkened rooms, munching magic pills and listening to repetitive electronic music." --Kristian Wilson, Nintendo, Inc, 1989
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