Does LW suck at shadow maps?

[pooby]

you need to UP the shadowmap quality by the sounds of things.. look in the light properties panel

[Macko-San]

Mhh, I was hoping I wouldn´t have to do that so I could keep render times down. The idea was to create an array of lights with low sized, but blurred, shadow maps, which would "melt" into one, soft shadow. This would recuire less memory than using one big shadowmap.

In 3dsmax the shadow looked great 256, but then I guess the same technique (is that how you spell technique?) won´t work in LW?

[kevman3d]

Firstly - Do you have any images of the problem you can post here? It may be that someone may see something in the image and have a solution for you.

Mhh, I was hoping I wouldn´t have to do that so I could keep render times down.

Shadowmaps are fast, but obviously they'll eat up a tonne of ram if they're too large. I'd crank them up and see if it improves anyway - You might find its just too low res to work nicely.

You can also try the spinning light trick in LW to achieve similiar effects (there's plenty of tutes online for that one).

[Qexit]

The spinning light trick is probably the best way to go and is really easy to set up since you can use Erkki Halkka's utilities to pretty much do it all for you :) Follow the link for more information:

http://www.kolumbus.fi/erkki.halkka/plugpak/

The utility that you want for the spinning light trick is Overcaster, but the others are all pretty useful too. You can download and use the whole PlugPak for free without any usage restrictions but with some delays and popup messages. To get a fully registered unhindered version is $50.

(http://www.kolumbus.fi/erkki.halla/plugpak/)

[gerardo]

I agree with kevman3d and Qexit. To use the spinning light trick instead of that 3D Max's trick is better for several reasons (btw, this 3D Max's trick is from the excelllent book of Jeremy Birn: Lighting and Rendering). The main reasons are better quality and render speed. Think on the number of lights. With that trick you mention you need 4 lights, but you can get better results with just 1 light and the spinning trick; why? because even if you are using AA Low Antialiasing, you have an equivalent of 5 lights (Normal Motion Blur) or 10 lights (Dithered Motion Blur) with only 1 light, if you are using AA Medium, you'll have about the double and so on. Just one light to get similar results of 5 or 10 lights mean faster renders. Also consider you get a better blending of the soft shadows (what is better quality) because LW merge more softly all passes when generates the final images (is even better than any subsamplig feature in any compositing sofware), and this is not only for shadows but rather for diffuse too. Besides consider with the spinning light trick you can increase the shadowmap resolution (since you need a lot of less lights), also you can use lower fuzziness on shadows, which offers more accurate shadows in small details. As far as I know, you can not apply the spinning trick on Max, but in LW you can, so take advantage of it :)


Gerardo

[blaqDeaph]

In 3dsmax the shadow looked great 256, but then I guess the same technique (is that how you spell technique?) won´t work in LW?

Try playing with the settings (try a value higher or lower), because they may not be equivalent in terms of what the numbers mean.

[xiao_x]

as i know,eki plugpak is not using shadow map from sport light,that plugin is using distance light and spinning trick:shrug: ,dunno,correct me if i`m wrong

[Qexit]

as i know,eki plugpak is not using shadow map from sport light,that plugin is using distance light and spinning trick:shrug: ,dunno,correct me if i`m wrongYou're wrong :twisted: Eki's Overcaster can use Spotlights, Distance Lights, Area Lights and Linear lights in any combination you choose. Have a read through the PlugPak FAQs. You can add extra lights through the Overcaster HUB. It's really very flexible :thumbsup:

[PixelInfected]

i don't know how max's shadow map work, but i can suggest some tricks :
1) high shadow fuzziness value = high shadow blur value (attention to not apply an exxagerated value or shadow will be unlinked from obj that project it).
2) shadow map angle = restrict area of shadow only for obj that must project shadow, usually is setup to fill the cone angle, but usually is too big for obj.

usually shadow map is something like a diffusion map projected from the light point, before to start render lw check all obj in front of light and build image that will be used for a shadow map.

256 x 256 pixel is very small shadow map, go in light view and reduce the shadow map angle.
like you can see in the picture, in first image 512 x 512 shadow map cover creature but most of pixel are filled from background
in the second image i restrict the shadow map angle to the creature.
with same 512 x 512 shadow map you can have a shadow map with a better quality.
have a nice work.

don't forget that at frame 0 motion blur not work, if you start key animation from 0.

[xiao_x]

You're wrong :twisted: Eki's Overcaster can use Spotlights, Distance Lights, Area Lights and Linear lights in any combination you choose. Have a read through the PlugPak FAQs. You can add extra lights through the Overcaster HUB. It's really very flexible :thumbsup:




oops,:blush: :argh: ,sorry dude,my mistake.i have change the light to other type before,but i just feel distance light is the most suitable to use for overcaster ,maybe i`m lousy,just say sorry agian with my mistake.

[dmaas]

These days I would almost say forget shadow maps and do soft lights with ray tracing or ambient occlusion...

[gerardo]

Maybe for some projects, but for some others, a skillful use of shadow maps are still faster than FPrime's raytrace_shadows or occlusion shaders, I mean, quite faster.



Gerardo

[PixelInfected]

for occlusion shader i can suggest you sg_occlusion, which is faster and better solution that you can find on lw free plugins, there is also an occlusion shader on ifw collection, but i nver tried it.

[gerardo]

Yea, SG_AmbOcc is great! :beer:




Gerardo

[Giacomo_M]

>These days I would almost say forget shadow maps and do soft lights with ray tracing or ambient occlusion...

I want to echo this. Using "Background Only" illumination is a *far* easier and cleaner way to get an "overcast" look. Generally I've found the render hit to be pretty small.

GM

PS. If you do use buffered shadows, however, my advice is don't waste your time on any size below 1500. The speed gained by decreasing the buffer size is negligible.

[Insider]

Up the values as been mentioned. Another trick is to make the spotlight wide and tight. That is, give it a wider spot angle, and move it in closer. You'll get cleaner shadow map edges.

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