GI in EI- question

[A.C. Farley]

No way to soften shadows?

[Martin Kay]

No way to soften shadows?

Hi. I've tried a few more scenes with soft spots and they seem ok... so lol!
I've noticed that a lot of EI users use RT lighting with the hard edge you get. I suppose this is ok for exteriors in bright sunlight as in 'reality' the shadows are to all extent and purpose almost dead sharp- they look it from a distance.

http://www.martinkay-3d.com/index.html

Martin K

[arketype]

Hi Martin-
Currently creating image based lighting with a skymap is the only practical way to get soft raytraced shadows in EI using normal lights. (there are RT soft shadows, but they are slow).

An HDR file used as a Skymap in v7 will cast very nice soft shadows.

Unfortunately, for an "interior" like you have in these tests, the ceiling and walls block the skymap. One of the major features announced for v8 is photon based lighting. Photons can be emitted from any light source, and can bounce 20 times or more, giving very realistic inter-object illumination. The GI engine will also be able to generate soft RT shadows for these light sources very quickly.

Attached below is a small preview of IBL using an HDR file from the Paralumino sets that I created.
This shows the rich, smooth shadows, and bright reflections possible wit IBL and HDR inside of v7.

[Martin Kay]

Hi Martin-
Currently creating image based lighting with a skymap is the only practical way to get soft shadows in EI. (there are RT soft shadows, but they are slow).

An HDR file used as a Skymap in v7 will cast very nice soft shadows.

Unfortunately, for an "interior" like you have in these tests, the ceiling and walls block the skymap. One of the major features announced for v8 is photon based lighting. Photons can be emitted from any light source, and can bounce 20 times or more, giving very realistic inter-object illumination. The GI engine will also be able to generate soft RT shadows for these light sources very quickly.

Hi Arketype, yes I have a demo of Vs 7 which I haven't loaded up yet- will wait until I'm more familiar with what's in 6.5. The Vs 7 demo only lasts 15 days for current users. It'll be interesting to compare render speed. 6.5 isn't too bad. Modo slows down when you pile the features on...

Martin K

[arketype]

Hey Martin,
It's necessary to get a good understanding of the GI engine under your belt before jumping into IBL with HDRI. That said, IBL can give you astounding results with very little setup time.

I am using my HDR skymaps for lighting, reflection, and refraction mapping on a daily basis. I often exceed the 1 million polygon mark, and rarely do I have still renderings that take longer than about 10 or 15 minutes (usually about 8x10 at 200 dpi). This usually includes raytraced transparent objects like glass and water ;)

Actually, I did not "get" the whole HDRI thing for v7 until I used the feature. Once I used it, I was sold, and I now use it in every project I can.

Good luck,

Dave

[Martin Kay]

Hey Martin,
It's necessary to get a good understanding of the GI engine under your belt before jumping into IBL with HDRI. That said, IBL can give you astounding results with very little setup time.

I am using my HDR skymaps for lighting, reflection, and refraction mapping on a daily basis. I often exceed the 1 million polygon mark, and rarely do I have still renderings that take longer than about 10 or 15 minutes (usually about 8x10 at 200 dpi). This usually includes raytraced transparent objects like glass and water ;)

Actually, I did not "get" the whole HDRI thing for v7 until I used the feature. Once I used it, I was sold, and I now use it in every project I can.

Good luck,

Dave

Hi Dave, when you say 'a good understanding ' of GI I assume you don't mean the 'radiosity' feature which 6.52 has, but the Global Illumination feature?

Martin K

[arketype]

Yes, exactly, GI= Global Illumination.
Radiosity is a much older technology based on pre-computation of lighting energy, and "burning" that data into vertices in the model. Subdividing the model into very dense meshes is necessary.

I don't think Radiosity has ever worked in any of the UB builds.

The GI system can be fast, but it is also easy to make it unbearably slow. It's good to get an understanding of what each GI variable does, and how to control the system as a whole.

There are training products available over at Paralumino.com if you need some extra info ;)

Good luck,
Dave

[Martin Kay]

Yes, exactly, GI= Global Illumination.
Radiosity is a much older technology based on pre-computation of lighting energy, and "burning" that data into vertices in the model. Subdividing the model into very dense meshes is necessary.

I don't think Radiosity has ever worked in any of the UB builds.

The GI system can be fast, but it is also easy to make it unbearably slow. It's good to get an understanding of what each GI variable does, and how to control the system as a whole.

There are training products available over at Paralumino.com if you need some extra info ;)

Good luck,
Dave

Thanks for the info!

Martin K

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.