HDRI Sharp shadows

[simmsimaging]

Could it be possible to control how sharp the sun shadows are? If they are always perfectly sharp this will have less value, but it is still a viable option for many cases.

[radiance]

Could it be possible to control how sharp the sun shadows are? If they are always perfectly sharp this will have less value, but it is still a viable option for many cases.

would'nt that destroy the concept of having a physically accurate sunlight model ?
it's not difficult to add though it should be easy to add a parameter that controls the size of the sun,
however i wonder if we need it.

Radiance

[sam75]

Could it be possible to control how sharp the sun shadows are? If they are always perfectly sharp this will have less value, but it is still a viable option for many cases.

would'nt that destroy the concept of having a physically accurate sunlight model ?
it's not difficult to add though it should be easy to add a parameter that controls the size of the sun,
however i wonder if we need it.

Radiance

perhaps just being able to control the level of accuracy of the hdr map ?

You said it would take longer to render with a more accurate hdri but for example with the benchmark scene I get 2.69MS/s with daylight and 3.91 with hdri

[pixelrush]

I'd go with a 'penumbra effect' via a sun size slider - neednt be much different, just a little. HDR lighting effect is typically fairly soft. If we could take the edge off sunlight in some cases it would be good.
Maybe radiance could hack in a different sun size and do a render comparison just to test the concept for us.

http://en.wikipedia.org/wiki/Umbra

[simmsimaging]

Could it be possible to control how sharp the sun shadows are? If they are always perfectly sharp this will have less value, but it is still a viable option for many cases.

would'nt that destroy the concept of having a physically accurate sunlight model ?
it's not difficult to add though it should be easy to add a parameter that controls the size of the sun,
however i wonder if we need it.

Radiance

I always find it funny where people tend to get particular about "physically accurate". You are already off the reserve for that anyway when mixing with HDRI are you not?

Personally, the only reason I ever cared about physical accuracy was for making my life easier - in that the CG world would behave more "intuitively" when accurate. Aside from that I couldn't care less as long as it looks good. That may just be me though

Anyway, having the ability to soften the shadows will allow you. To better match atmospheric effects on sunlight (some anyway) and. Will make it more versatile as a lighting tool. I would vote to add it if it's not too difficult.

[pixelrush]

I think Octane can still adhere to being 'physically accurate' as its basis.
If there can be a little wiggle room around the edges for 'artisitic license' and functionality that makes it easier to use or the results are more pleasing I think thats worth having.
Some unbiased renders have over emphasised accuracy at the expense of useablity and practicality. Ideally you want a physics degree to operate them and fully appreciate the results.
A 'sun softener' and 'enough bump for bricks' may offend the purist but if they can work well and if it helps get the job done it ought to be considered.
Many Octane customers will be wanting to do commercial renders where quality is important but time is money.
A little corner cutting here and there to that effect might not be such a bad thing.
my few cents

[Rhodesy]

+ one for a sun size multiplier!

[radiance]

i can do a sun size parameter, eg the smaller the sun the more it will become a 'point light' and the more parallel the light becomes.
what do you think of that ?

Radiance

[n1k]

+1

Cheers,
n1k

[pixelrush]

well how does it work presently?
will making it smaller/bigger make the shadows a little fuzzy?
give us an example of the effect to look at and we'll tell you...

edit: how about 2 or 3 virtual point suns superimposed at slightly different distances, angles and strengths for a pseudo blur/penumbra?
I guess this is *a bit* like a stereo image in reverse..