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pilkiwilky
09-15-2005, 02:02 PM
I have a long animation to render and the metal I have needs some reflection blurring (it is being raytraced) I have blurred the spherical map but I need to blur the raytracing too. Does anyone know how much the reflection blurring affects the render times.

thanks

Schwing
09-15-2005, 02:27 PM
I have a long animation to render and the metal I have needs some reflection blurring (it is being raytraced) I have blurred the spherical map but I need to blur the raytracing too. Does anyone know how much the reflection blurring affects the render times.

thanks

For me, about double or triple the time. But experiment with your own scene. :thumbsup:

Lightwolf
09-15-2005, 03:02 PM
If your AA is high enough, a micro-bump could do the trick as well (i.e. fractal noise in the mm range depending on the scene, at 1-5% or so.).
After all, surface roughness is why blurred reflections occur in real life as well.

Cheers,
Mike

Schwing
09-15-2005, 03:07 PM
That sounds like the way to do it. :i_agree:

Captain Obvious
09-16-2005, 02:08 AM
If you want smoother reflection blurring, you can animate the fractal noise texture (simply move it around a bit) and use motion blur. This will smoothen it a bit. I had one scene that rendered in about eleven minutes. I turned off blured reflections on all the objects, and it rendered in less than thirty seconds. :screwy:

lardbros
09-17-2005, 01:25 AM
You could also try out "soften reflections" in the image processing. It will unfortunately soften ALL your reflections, but it's bloody quick. It sorta smudges them as a post process.

Captain Obvious
09-17-2005, 05:13 AM
It also doesn't look very good, since it doesn't smooth the reflections based on the distance between the reflector and the object being reflected.

lardbros
09-17-2005, 09:30 AM
Yeah, that's true, but it was only anotherr suggestion... the more the merrier in my opinion.

Captain Obvious
09-17-2005, 05:45 PM
The best method I can think of is to use a bump map for blurring out the reflections (it's raytraced to perfection, and offers great control, you can even create anisotropic reflections this way), and then applying a very weak smooth reflection image filter, scaled by surface buffers to control which surfaces recieve the smoothing. This will effectively remove noise from the reflections, and still be actual raytraced reflection blur, with a very low render time hit. Awesome.