how to use raytrace shadow make soft(smooth) shadow without area light?

[ribok7]

would using soft shadows solve your problem?

:beer:

[tachy0n]

You could render a seperate shadow pass and blur in post, or use HDR lighting with FG.

[StefanA]

try this
-------------------------------------------------------------------
CreatePrim "Grid", "MeshSurface"
CreatePrim "Cube", "MeshSurface"
SetValue "cube.cube.length", 1
Translate , 0, 0.502458210422812, 0, siRelative, siView, siObj, siXYZ
DeselectAll
GetPrimLight "Spot.Preset", "Spot"
SetValue "Spot.light.ShadowMap", True
SetValue "ViewRenderOptions.UseShadowMaps", True
SetValue "Passes.*.RenderOptions.UseShadowMaps", True
SetValue "Spot.light.soft_light.shadow", True
SetValue "Spot.light.soft_light.factor", 0
SetValue "Spot.light.ShadowMapSoft", 0.102362
-----------------------------------------------------------------------

best regards

.stefan andersson

[Atyss]

Hi Stefan,

The guy asked for raytraced shadows.


There is no way to do soft raytraced shadows without area lights. The only solution is to do it in post, as tachy0n suggested.


Cheers
Bernard

[rayguo]

thanks all!

i ask this question because i found that raytrace cant create smooth shadow!

but the 3.0 book tell me the raytrace can create realistic shadow

i think realistic shadow=smooth shadow

so i want to know how use raytrace shadow create smooth shadow without use area light! :))

[Atyss]

Reread my answer, it's all there.

[BiTMAP]

make any light you want and then put the shadows on and then play with umbra that changes how harshe it is.

[rayguo]

i see now!!

thank you all!!

:applause:

[marci2001]

Move your lightsource, enable motion blur.
its quite fake

(you'll need great shutter)

there was in XSI1.5 another option, maybe it was due to a bug.
unfortunatly I don't remember exactly, but somerthing you had to do with motion blur in renderpanel, and it produced something you liked
that's quite a help

M:rolleyes:

[BiTMAP]

actualy if u just play with the umbra you get nice shadows without having to make bad mistakes with motion blur.

[rayguo]

but i remember the umbra cant create smooth shadow by itself

is it right?

[BiTMAP]

no no what i end up is that umbra creates a softer shadow edge when you tweek it, or a harder one, it seems to be the light focus almost...

[Atyss]

I'd be interested to know how you use the Umbra parameter to create soft shadows. Afaik the umbra is the intensity of the shadow, not its softness.

Cheers
Bernard

[BiTMAP]

I know when i've played with the umbra setting I've ended up having smoother shadows and such, as well stronger or weaker shadows.

[ggg]

Originally posted by BiTMAP
no no what i end up is that umbra creates a softer shadow edge when you tweek it, or a harder one, it seems to be the light focus almost...
I decided not to respond to this before, but since the claim is being repeated I have to respond, sorry but it is incorrect.

The very defnition of umbra is: the area not visible to a light source.

penumbra is defined as: the area partly seen by the light source such as by an area light.

As rayguo said "the umbra cant create smooth shadow by itself " As Bernard said "the umbra parameter [in XSI] effects the intensity of the shadow not softness.

rayguo is asking about point not area lights.
the suggestions made, shadow maps(not rtrace really as wanted) etc. will soften the edges

[Atyss]

Originally posted by BiTMAP
I know when i've played with the umbra setting I've ended up having smoother shadows and such, as well stronger or weaker shadows.

Really? Can you repeat it for us?

Thanks
Bernard

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