Soft Shadow Settings

[Mandrake]

Anyone have these setting figured out yet?
I'm wondering about ground shadows.
I'm wondering what happens as you increase the # of Soft Shadow Samples.

[sjefen]

I haven't tested it very much. But if you increase the soft shadow samples the rendertimes will increase to.
I also think that if you increase the radius of the soft shadows the rendertimes will increase.

[Buzzzzz]

I'm working on a scene that I tried the soft shadows in the sun settings and set the diameter to around 30 and samples to 10 and the low haze at the horizon was terrible with splotches and it seemed to take forever to render. So I said screw this and disabled it. It wasn't my atmo, clouds or render quality settings either because they looked fine without the soft shadows enabled. What I did discover was when I used java's Fill Light Setup with the soft Shadows enabled in that node (at default settings) it seemed to help. Maybe one of the testers can tell us their thoughts? 

[moodflow]

Soft shadows "work" by using multiple point lights.  The more you have, the more accurate the shadows (but the longer the render times). 

Soft shadows mainly just simulate the fact that the sun is a disk of light, rather than a point light.  We are used to seeing everything lit this way on Earth.

The radius increases just simulate more diffuse lighting, simulating a more overcast day and/or a larger sun disk.  Provided samples stay the same, the rendertimes will not increase (theoretically).

[sjefen]

The radius increases just simulate more diffuse lighting, simulating a more overcast day and/or a larger sun disk.  Provided samples stay the same, the rendertimes will not increase (theoretically).

I thought I remember it taking longer to render when I only increased the radius. But I may be wrong.
Anyways.... Is it affecting the clouds?

[moodflow]

The radius increases just simulate more diffuse lighting, simulating a more overcast day and/or a larger sun disk.  Provided samples stay the same, the rendertimes will not increase (theoretically).

I thought I remember it taking longer to render when I only increased the radius. But I may be wrong.
Anyways.... Is it affecting the clouds?

I believe I remember hearing Matt stating he has it turned off for clouds, as there would be no noticeable effect, yet it would increase the rendertime.  I can't find the post at this time.

[Mandrake]

RArcher did a great test of this function over at Ashundar.
http://www.ashundar.com/index.php?topic=3953.0

[Buzzzzz]

The radius increases just simulate more diffuse lighting, simulating a more overcast day and/or a larger sun disk.  Provided samples stay the same, the rendertimes will not increase (theoretically).

I thought I remember it taking longer to render when I only increased the radius. But I may be wrong.
Anyways.... Is it affecting the clouds?

I believe I remember hearing Matt stating he has it turned off for clouds, as there would be no noticeable effect, yet it would increase the rendertime.  I can't find the post at this time.

Well damn I thought it effected the clouds also. LOL Sure would be nice.

[Volker Harun]

Follow this link: http://forums.planetside.co.uk/index.php?topic=1624.msg18200#msg18200

And a bit farther down:

... the built-in soft shadows use less shadow samples when calculating the light falling on the clouds and atmosphere, because the quality reduction there is less noticeable. ...

Volker

[Matt]

Soft shadows do affect clouds and atmosphere. Clouds/atmosphere cast soft shadows, and soft shadows are received by clouds/atmosphere. However, the number of samples used to figure out the soft shadows received by clouds and atmosphere is much less than the value you enter into the setting for the sunlight or lightsource. In many situations this is sufficient to achieve good quality soft shadows in clouds/atmosphere, but if there is too much noise in the clouds or atmosphere you will need to increase cloud/atmosphere samples (soft shadow samples would have little effect in these cases).

Matt

[Matt]

Increasing soft shadow diameter does increase render times, but not proportionally. When the diameter increases, the renderer is less able to take advantage of coherence between individual samples and caching schemes are less effective. But the largest effect on render times is usually the number of soft shadow samples.

Matt

[Matt]

I don't know what might be causing those splotches, Buzzzzz. Do you have a .tgd we can test?

Matt