Zanzo opened this issue on Aug 11, 2009 · 95 posts
Zanzo posted Tue, 11 August 2009 at 8:06 AM
IBL + IDL .. Yay or nay?
manoloz posted Tue, 11 August 2009 at 8:13 AM
yay
still hooked to real life and enjoying the siesta!
Visit my blog! :D
Visit my portfolio! :D
cspear posted Tue, 11 August 2009 at 8:18 AM
I did a version with IBL off but didn't keep it for comparison - I don't think there was a huge difference.
Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)
PoserPro 11 - Units: Metres
Adobe CC 2017
bagginsbill posted Tue, 11 August 2009 at 8:18 AM
IBL works with IDL, but it works differently than without IDL.
When IDL is enabled, the colors in the IBL are projected on a gigantic virtual sphere that surrounds your scene. If your subject is inside a close room, the light from the IBL is blocked. Without IDL, the light would reach everywhere, passing right through all surfaces.
If you are just doing a figure and it is not enclosed, the IBL light will reach it, but it won't pass through arms and legs. Thus, the shadows produced are correct.
Light-based AO is inferior to this and is ignored when IDL + IBL is used. Even if you turn AO on for the light, the renderer ignores that and uses the superior rules afforded by IDL.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 8:21 AM
Oh I forgot to mention. If you use my EnvSphere, there is no point in using an IBL. The virtual IBL sphere is bigger (infinite) and so the light will come from the EnvSphere, which completely encloses your scene.
With IDL, the lighting from the EnvSphere is automatically correct and matches the scenery you load into it. Further, in the enclosed room above, the EnvSphere only provides light that can be seen through the windows. The room blocks the rest of it.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
cspear posted Tue, 11 August 2009 at 8:29 AM
Quote - Oh I forgot to mention. If you use my EnvSphere, there is no point in using an IBL. The virtual IBL sphere is bigger (infinite) and so the light will come from the EnvSphere, which completely encloses your scene.
BB, thanks for clearing that one up... I think you've told us this several times over the last few days but it's only just sunk in with me.
Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)
PoserPro 11 - Units: Metres
Adobe CC 2017
Zanzo posted Tue, 11 August 2009 at 8:37 AM
Quote - > Quote - Oh I forgot to mention. If you use my EnvSphere, there is no point in using an IBL. The virtual IBL sphere is bigger (infinite) and so the light will come from the EnvSphere, which completely encloses your scene.
BB, thanks for clearing that one up... I think you've told us this several times over the last few days but it's only just sunk in with me.
Yea this just clicked in my head :)
Baggins ftw :)
LukeA posted Tue, 11 August 2009 at 10:04 AM
lululee posted Tue, 11 August 2009 at 10:15 AM
What would we do without you, BB.
You truly have patience.
cheerio
lululee
bagginsbill posted Tue, 11 August 2009 at 10:56 AM
Well, without me, you'd probably have the old library GUI and nobody would be complaining about small thumbnails. ;-)
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
lululee posted Tue, 11 August 2009 at 12:23 PM
BB,
As a vendor, I have made a lot of mistakes when trying to push the envelope. It is devastating.
I used to show horses. When I got thrown off the horse or lost a competition my mother always instructed me to get back on the horse saying I could only quit when I got it right or won. I became a champion horsewoman because of it.
You are doing something very complex. Something no one else would take on. So, it is not perfect the first time. You are still a champion and will push the envelope for all of us. You will bring out a fantastic new library soon. It will be way better than the old one because now you know want users really want. In 3 months all of this will be forgotten.
Steady on my friend, you will overcome.
cheerio
lululee
cspear posted Tue, 11 August 2009 at 1:10 PM
Except, it may be useful to do just that in some circumstances. These are crops from a couple of renders, same setup for each (car, figure, env sphere), the only difference being the use of IBL with AO set at 2.0 on the second image. That seemed to have improved the shadows on the face.
That there is a difference is shown on the right. If this is a bug, it could be a useful one!
Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)
PoserPro 11 - Units: Metres
Adobe CC 2017
cspear posted Tue, 11 August 2009 at 1:22 PM
The image is self-explanatory: identical setup, the only difference being Ray-Traced shadows vs. Depth-Mapped shadows.
I just ran the same test with a different figure in the scene - this one had hair with a specular map - and got even more of a difference: ray-traced 21:45, depth-mapped 7:14.
EDIT: is it just me, or does the colour of Miki's suit look slightly different?
Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)
PoserPro 11 - Units: Metres
Adobe CC 2017
DarksealStudios posted Tue, 11 August 2009 at 1:39 PM
the skin looks alittle tiny bit more saturated in the 2nd one, but maybe its just me.
bagginsbill posted Tue, 11 August 2009 at 1:55 PM
Quote - > Quote - If you use my EnvSphere, there is no point in using an IBL.
Except, it may be useful to do just that in some circumstances. These are crops from a couple of renders, same setup for each (car, figure, env sphere), the only difference being the use of IBL with AO set at 2.0 on the second image. That seemed to have improved the shadows on the face.
That there is a difference is shown on the right. If this is a bug, it could be a useful one!
Huh. You're right. I did not do a detailed test until now. Despite my own advice to the contrary, I trusted my eyes, and what I thought I saw was that IBL had no impact when the ESphere was present.
So I just did an experiment. I set up an IBL with only green in it. I set up an EnvSphere with only red in it. I rendered some white props.
With only the IBL, everything is a pure shade of green.
With only the EnvSphere, everything is a pure shade of red.
With both, it looks pure red, but there is a tiny bit of green in it!!!!!!
This is a bug. Don't count on it in the future.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 1:56 PM
This is the IBL render.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 1:56 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 1:56 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 2:05 PM
Make the EnvSphere somewhat transparent. This lets the IBL light leak through. Here my EnvSphere is 50% transparent. Looking directly at it, it is still red, because it is self-lit and pays no attention to the IBL. But the props are picking up half the light from the EnvSphere and half the light from the IBL. 50% red + 50% green = dark yellow.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Synpainter posted Tue, 11 August 2009 at 2:26 PM
Bookmark.
pjz99 posted Tue, 11 August 2009 at 2:29 PM
There's an important difference between how an IBL light can behave with indirect lighting enabled, and how an environment sphere (or other geometry) that emits Ambient will behave: the IBL can have shadows turned off. Ambient emitted from a material will always be occluded by polygons that are not transparent; IBL with shadows off will always pass through it - AND bounce.
Cspear, according to Stewer, when indirect lighting is enabled, light-based AO is skipped, so you might as well not bother with it.
bagginsbill posted Tue, 11 August 2009 at 2:46 PM
PJ - my EnvSphere has shadows turned off and my IBl has no shadows enabled of any kind. Why are you contradicting the evidence I demonstrated? Not being an ass. I'm wondering if you've tried it a different way than I did.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
IsaoShi posted Tue, 11 August 2009 at 2:47 PM
Ummm, isn't there a contradiction here?
One says that IBL with IDL will be occluded.
One says that IBL with IDL will not be occluded.
What I thought I had learnt is that IBL with IDL does not work as IBL at all, but as ambient light emitted from a virtual all-enclosing sphere. So it will be occluded.
(edit) oops, cross-post, never mind!
"If I were a shadow, I know I wouldn't like to be half of
what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki
Murakami)
bagginsbill posted Tue, 11 August 2009 at 3:10 PM
A flattened sphere hovering over the ground.
The only light is an IBL.
On the IBL, shadows are disabled. AO is disabled.
On the sphere, Cast Shadows is disabled.
Yet there is occlusion under it. I don't see what else there is to say about this. The only possible conclusion is that IDL looks to the first opaque surface and that's where bounced light comes from. If it never reaches a surface, then bounced light comes from the IBL, "mounted" on an infinite sphere enclosing the scene.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 3:12 PM
By the way, I just demonstrated another bug. Who sees it?
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 3:15 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
cspear posted Tue, 11 August 2009 at 3:23 PM
Shadows enabled?
Windows 10 x64 Pro - Intel Xeon E5450 @ 3.00GHz (x2)
PoserPro 11 - Units: Metres
Adobe CC 2017
Nyghtfall posted Tue, 11 August 2009 at 3:39 PM
Quote - Compare this with the earlier one. There is a thin box under the flattened sphere. What is different?
There's a shadow on the bottom half of the sphere in the second image.
bagginsbill posted Tue, 11 August 2009 at 3:47 PM
Quote - > Quote - Compare this with the earlier one. There is a thin box under the flattened sphere. What is different?
There's a shadow on the bottom half of the sphere in the second image.
Right!
It would appear that when IDL sends out a ray from the bottom of a sphere, it passes right through the Ground without realizing it, and picks up light from the IBL, when it should not.
When I put a flat box there, it saw the box, same as it should have seen the ground.
Poser 8 Ground seems very buggy. I have found more than one situation where Poser seemed unaware that the ground exists.
For example. Load a couple props. Go into the material room. Click on one prop - its material gets selected into the material room display. Click on another prop - that one gets selected.
Now click on the ground. It selects the Background material instead of the Ground material.
It acts like the Ground isn't there.
Uli told me the Ground is not real geometry - it is procedural. It seems that not all the parts of Poser are procedural-geometry aware.
They should have got rid of that Ground and just used a prop for real. These problems wouldn't exist.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Whichway posted Tue, 11 August 2009 at 3:57 PM
On my Poser 8, the GROUND material comes up with Shadow_Catch_Only enabled by default. According to the manual, this means it is transparent to light, but catches shadows produced by other objects. This sounds roughly consistent with what you're seeing to me. That would mean it's not a bug but a feature, I think.
Whichway
bagginsbill posted Tue, 11 August 2009 at 4:00 PM
Have you forgotten I'm a Poser God? I have my own shadow catcher that is far superior - look in my free stuff.
First thing I did (FIRST THING) was make the ground normal. Clearly it's not a shadow catcher because you can see it in my render.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 4:03 PM
It picks up light from the ground, but doesn't count for occlusion.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Whichway posted Tue, 11 August 2009 at 4:07 PM
Sorry, (dang, I'll get one of them right one of these days.) My only defense is that I don't think you said - at least I didn't read - anywhere nearby that you'd normalized the ground, but your comment about it being visible is certainly valid. Your devoted acolyte quails before your august presence.
Whichway
bagginsbill posted Tue, 11 August 2009 at 4:07 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 4:15 PM
That doesn't work either.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 4:17 PM
I'm switching my default scene to a scaled box. That's the only thing that works right.
I wonder if walls made of single-sided objects have a problem, too.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
pjz99 posted Tue, 11 August 2009 at 4:19 PM
Because they do indeed behave differently. See the linked file.
This is with an IBL, shadows turned off:
pjz99 posted Tue, 11 August 2009 at 4:19 PM
pjz99 posted Tue, 11 August 2009 at 4:21 PM
and for reference, another "room" box is included, "Room Outer", with the normals facing out. With both the IBL and the environment sphere, it occludes all incoming light (which imo shows again that including normal facing in GI calculations is not a good idea, it shouldn't matter).
Edit: to clarify, it doesn't work like either of us thought it did; with an IBL that has shadows turned off, light passes in through the backfacing normals; with the environment sphere, it is occluded. With outward-facing normals, both are occluded.
bagginsbill posted Tue, 11 August 2009 at 5:18 PM
Wait, I don't even know what you're talking about anymore.
IBL with shadows off? You mean shadows, like we use on a directional light, raytraced or depth-mapped shadows? You're not talking about AO? Why are we talking about that now? On an IBL, the "Shadows" property is identical to an infinite light, and is actually nonsense and has always been that way.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 5:37 PM
Also, you last said "light passes in through the backfacing normals".
Well, that appears to depend on the size of the polygons or whether we're inside or SOMETHING, I don't know which.
I'm getting confused now with my current tests. Small one-sided squares don't seem to block IBL at all, but my environment sphere blocks IBL even with normals in or out.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Iuvenis_Scriptor posted Tue, 11 August 2009 at 5:39 PM
I used Bagginsbill's Environment Sphere with a panoramic photo from Flickr. The shaders/textures and morph are of my own design. Comments are welcome!
On the subject of occlusion, I've experienced similar issues. When I built my Photo Studio using planes as walls, there was almost no shading at the corners where the walls met. When I switched to thinned-down cubes, the missing occlusion magically appeared!
bagginsbill posted Tue, 11 August 2009 at 5:47 PM
IS:
Are you using GC shaders with IDL? I haven't tested extensively, but I think you really can't. The data that GC shaders reutrn is for how to make that luminance on a screen. For light measurement purposes, those numbers are way too high. That would cause over-exposure for sure. That's why linear rendering is so important.
With Poser 8 and IDL, dump GC shaders altogether. Use linear output only from shaders. Make sure all diffuse calculations throw less light than arrives (Diffuse_Value < 1). Use HSV Exponential Tone Mapping at 2.2 for the final adjustment (approximately) to sRGB color space.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
FrankT posted Tue, 11 August 2009 at 5:54 PM
Quote - I'm getting confused now with my current tests. Small one-sided squares don't seem to block IBL at all, but my environment sphere blocks IBL even with normals in or out.
Dunno if this is relevant but Poser 7 used to have all sorts of problems with small props. Firefly used to produce some very odd shadows (square shadows from spheres for e.g)
bagginsbill posted Tue, 11 August 2009 at 6:03 PM
When I say small, I don't mean inches. I mean a 10 foot wall 5 feet away versus a 1000 foot wall 500 feet away.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:07 PM
OK I've found something else completely strange.
PJ - you said based on which way a normal faces, it may or may not let IBL light through under IDL.
How does this grab you?
Load a subject prop. Set up a constant light gray IBL, no shadows no AO. Render. The prop looks uniformly lit.
Load a one-sided square. (EDIT: MAKE IT BLACK) Scale it up 500% (EDIT: I said 5000% first time - I meant 500%) and position it beside the prop so you can see the prop, but this wall can block a significant angle of the environment. Render again. No change to the appearance of the prop.
Now duplicate the wall, so there are two of them. Render again. The wall now blocks IBL and the surface facing the wall are darker.
What is your theory?
Variations:
Turn either or both walls around, so the normals face towards the prop. Same thing happens. One alone does not block IBL, two do.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:11 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:11 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:12 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:14 PM
I had all shadows and AO on lights, props, everything turned off.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:17 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:20 PM
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 6:23 PM
I don't have a theory that makes a prediction. At this point, all I know is we were seeing different things and arriving at different hypotheses. I used a huge dome or sphere. You used a "small" box. (Small being relative. The surface area of my dome is 3.5 million square feet.)
One-sided polygons don't behave the same in these two scenarios.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Miss Nancy posted Tue, 11 August 2009 at 6:32 PM
I also found in poser 7 that FFRender works better with GIVariables activated if walls/floor are made of poser boxes rather than planes. it seems to prefer an object with thickness to bounce off of.
pjz99 posted Tue, 11 August 2009 at 6:50 PM
Quote - You're not talking about AO?
Did I say I was talking about AO? AO = AO, Shadows = Shadows. I don't know why you would read "shadows" and interpret it as "AO".
pjz99 posted Tue, 11 August 2009 at 6:54 PM
Quote - Load a one-sided square. ...What is your theory?
The one-sided square prop is a single polygon, and it's a common thing in GI rendering in other apps that polygon density will affect accuracy of how GI is applied. It has to do with the number of samples being allocated on a per-polygon basis. I would expect a higher poly object of the same shape to behave differently (more accurately). I'm not sure of the point you were trying to make, but this is still useful information even if it doesn't have to do with what you're getting at.
Whichway posted Tue, 11 August 2009 at 7:16 PM
bagginsbill -> Quote -
Are you using GC shaders with IDL? I haven't tested extensively, but I think you really can't. The data that GC shaders reutrn is for how to make that luminance on a screen. For light measurement purposes, those numbers are way too high. That would cause over-exposure for sure. That's why linear rendering is so important.
With Poser 8 and IDL, dump GC shaders altogether. Use linear output only from shaders. Make sure all diffuse calculations throw less light than arrives (Diffuse_Value < 1). Use HSV Exponential Tone Mapping at 2.2 for the final adjustment (approximately) to sRGB color space.
Oh, brother, I wish you hadn't said that. It had crossed my mind once but I'd firmly repressed it. IF this IDL is really working in linear space, then the "right" answer would be to un-GC the input color maps, but not GC the shader outputs; Tone Mapping at 2.2 would then properly, I think, GC the final image. BUT, what about the direct light hitting the same shaders? I doubt that part got rewritten to work in linear space - it would break everything - and direct lighting probably dominates in lots of scenes. I don't think you can have both right at the same time if IDL is really linear.
Whichway
[Trembling in fear of a divine thunderbolt.]
bagginsbill posted Tue, 11 August 2009 at 7:17 PM
Quote - > Quote - You're not talking about AO?
Did I say I was talking about AO? AO = AO, Shadows = Shadows. I don't know why you would read "shadows" and interpret it as "AO".
Because I know you're good with CG. In my mind, directional shadows on IBL is nonsense.
So, I did not even begin to imagine you'd ever make the mistake of using a directional shadow system on an omnidirectional light source. That makes no sense. So I didn't see why you'd even bring it up, when discussing how IBL works. it wasn't relevant to even discuss directional shadows on IBL, when the IBL is used for ambient lighting, which is 99.99% of the time.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 7:20 PM
Quote - > Quote - Load a one-sided square. ...What is your theory?
The one-sided square prop is a single polygon, and it's a common thing in GI rendering in other apps that polygon density will affect accuracy of how GI is applied. It has to do with the number of samples being allocated on a per-polygon basis. I would expect a higher poly object of the same shape to behave differently (more accurately). I'm not sure of the point you were trying to make, but this is still useful information even if it doesn't have to do with what you're getting at.
Now you seem combative. I dont' know why. If I do the same demonstration with a wall made of 10,000 polygons, does that change anything? Further, how does a denser set of vertices come into play, when simply duplicating the single polygon suddenly produced a completely different outcome?
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Iuvenis_Scriptor posted Tue, 11 August 2009 at 7:40 PM
Attached Link: http://www.hsmespanol.com/IL-Tests.jpg
Okay, BB, I've run some tests Ironically, it seems that when I follow your advice and turn off shader-based GC in favor of HSVE, that's when IL washes out the AO and oversaturates the character. In my opinion, the middle image is the best of the three.From top to bottom:
IBL-based ambient lighting with shader-based GC and AO, no HSVE
IL-based ambient lighting with shader-based GC and AO, no HSVE
IL-based ambient lighting with light-based AO and HSVE
bagginsbill posted Tue, 11 August 2009 at 9:09 PM
Well the oversaturation comes from the fake SSS factors. When we build shader-GC, the effect of the fake SSS is pretty weak, because the final GC step severely desaturates. Most of the anti-GC'd incoming material is hypersaturated so it comes out right. But I at least never bothered to put an incoming GC on the shade of red I use for SSS.
Basically, the fix is to simply use a less saturated and less bright red for faking SSS. Then HSVE works fine.
But I have to say, #2 looks GREAT.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
pjz99 posted Tue, 11 August 2009 at 9:32 PM
Quote - So, I did not even begin to imagine you'd ever make the mistake of using a directional shadow system on an omnidirectional light source. That makes no sense. So I didn't see why you'd even bring it up, when discussing how IBL works. it wasn't relevant to even discuss directional shadows on IBL, when the IBL is used for ambient lighting, which is 99.99% of the time.
And I don't know why you brought up AO, since Stefan explained that when indirect lighting is enabled, light-based AO is skipped. I'm assuming he knows what he's talking about, but assumptions can be perilous things.
Quote - Now you seem combative. I dont' know why.
I don't know why it seems that way to you either. I suggest you re-examine my posts and check your conclusion.
Quote - If I do the same demonstration with a wall made of 10,000 polygons, does that change anything? Further, how does a denser set of vertices come into play, when simply duplicating the single polygon suddenly produced a completely different outcome?
You're in a much better position to find out for sure, since you're in regular communication with Stefan. Ask him. Since I don't know the internals of Poser's GI algo (even if I did, I wouldn't really understand them) it is likely that he will give you a better answer.
HeyDork posted Tue, 11 August 2009 at 9:44 PM
You both can come off like pompous asses.
For some reason Pjz seems to think the more of an ass he is the more people will take him as a force to be reckoned with, yet he wastes BB's valuable time in another thread rendering w/ poly smoothing "on". Rookie mistake.
I think BB is a misunderstood genius dork. Very, very good at math but tends to talk down to some, not communicate with others, and is pleasant to those he chooses to be.
You both should shack up together! lol.
pjz99 posted Tue, 11 August 2009 at 9:47 PM
It is very important to me that random people on an internet discussion board think that I am a force to be reckoned with. I demand that you all bow and kiss my pinky toe. Not fucking around here.
bagginsbill posted Tue, 11 August 2009 at 9:57 PM
Well I've done enough experiments to confirm a working hypothesis. It may not be 100% correct yet - there could be some exceptions. I did not do extensive experimenting with polygon density - just a handful of cases involving objects from 1 to a few hundred polygons.
Given a subject, such as a sphere in the middle of the scene, and you want to know how IBL or a self-lit surrounding prop such as the environment sphere or a box will affect the subject, here is the answer. IBL is effectively an infinite virtual sphere, so the analysis is the same as for a glowing prop that surrounds the scene, even if that prop isn't spherical.
Given any point on the subject, imagine a line passing from there to all the points of the glowing environment. If any given line passes through two opaque polygons, then the IDL contribution to lighting the subject from that area of the glowing environment is zero. Period. Doesn't matter which way these polygons are facing, or if shadows are off for the occluding polygons.
If there is nothing in between, the full effect of the glowing light source will be used.
If there is exactly ONE polygon between, then the amount of the glowing light source leaking through that polygon depends on the distance of that occluding polygon from the subject. If the distance is less than 1 inch, as I showed with props on the Ground or one-sided square as a wall, nearly 100% of the light will leak through. I tested this with a box, too, although it was difficult to get the camera inside a small box. If the distance to the occluding polygon is on the order of tens of feet, about half leaks through. If it is 750 feet (my EnvSphere radius), only about 6% leaks through. I could never get it to go to zero.
That's it.
Props that represent bounded volumes will reliably block IBL 100% because IBL will not leak through two polygons on the same line. In order to leak through a bounded volume, it has to go in and go out - that's two polygons. So a nearby box or cylinder always throws an occlusion shadow.
However, even a pair of parallel squares, perfectly in alignment, will block the light, although technically there is no inside/outside in this case. It's a simple matter of passing through two, even if simultaneously.
Any time you have only a single surface between the subject and the diffuse light source, the diffuse light will leak through. This is even true of nested spheres.
If you place two nested spheres around your subject, and you make them both black, your subject will receive no light from IDL. If the outer one is glowing red, the amount of red that leaks through will depend on the radius of the inner one, because the inner sphere is the only polygon between the subject and the outer sphere. The inner sphere glow will be used 100% in either case. The total diffuse luminance will be the inner sphere glow plus some fraction of the outer sphere glow.
If you have 3 nested spheres, the outermost, even if glowing, will not light the subject, because to reach it it would pass through two polygons.
I have demos, but I'm getting pretty tired. I'll post them another day.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 9:59 PM
By the way, I'm just ignoring the bullshit. This is really interesting to me and it explains a lot of things, like why the ground doesn't work right.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
HeyDork posted Tue, 11 August 2009 at 9:59 PM
You seem to think it necessary to be in control, or a teacher...when no one has really asked you to be.
http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2778765
*"I told you this at least twice, and in general I explained this 6 or 7 times to various people who asked.."
*So this person wanted to share what they have learned, so what? You felt it necessary to demean them with your snotty, "I told you so comment?"
You need help.
Miss Nancy posted Tue, 11 August 2009 at 10:23 PM
well, anyway, we appreciate bill's input here. his genius includes being able to investigate and explain all these items in a logical and scientific manner.
pjz99 posted Tue, 11 August 2009 at 10:34 PM
Quote - Props that represent bounded volumes will reliably block IBL 100% because IBL will not leak through two polygons on the same line.
I get the same thing also. Very unexpected (you see, assumptions are perilous). Although, when foremost normals are facing away from the camera (as in, a clear line of sight to the camera), the renderer appears to do something very different from when normals are facing towards it, even though the Normals_Foward property is set for all materials. This is probably not good.
edit: err, the very different thing when rendering back-facing normals is "go very slowly"
bagginsbill posted Tue, 11 August 2009 at 10:59 PM
Not good to view the back side of a polygon - takes forever to render.
I'm off to bed, but I did do one good demo render.
Ground plane, two dark one-sided squares, very large, and two spheres.
Light is uniform white IBL, 80% intensity.
Observe the differences in the spheres. The one on the lower right is occluded by two polygons to the left, so its left edge is strongly occluded. The ball on the left is only occluded by one wall on either side, so both left and right edges are bright. The ball on the left, being sandwiched is picking up some occlusion from the more distant parts of the walls.
Observe the bottoms of the spheres. The upper left is 15 inches from the floor and the bottom is somewhat occluded by the ground plane. The one on the right, being only 5 inches from the floor, is experiencing very little occlusion from the ground plane.
The ground plane is experiencing strong occlusion where it is hidden by both walls, on the right side. I didn't include it in this composition, but the to the left of both walls it is also strongly occluded.
Between the walls, there is very little occlusion on the ground, mostly from the distant (higher) parts of the walls and some mutual occlusion between the left ball and the ground. The right side of the ground is also experience proper strong occlusion from the nearer ball.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Iuvenis_Scriptor posted Tue, 11 August 2009 at 10:59 PM
Quote - But I have to say, #2 looks GREAT.
While there's probably still loads more I could learn from you, BB, I can't help but feel incredibly vindicated having received an oughtright compliment from the Great Poser Guru himself!
bagginsbill posted Tue, 11 August 2009 at 11:09 PM
I got this by duplicating both walls, and adding a large one-sided square below the ground.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Tue, 11 August 2009 at 11:14 PM
OK now I'm really going to sleep.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Believable3D posted Wed, 12 August 2009 at 12:18 AM
Quote - I got rid of the light leak between the wall and ground by lowering the walls two inches below the ground.
That's an interesting discovery. It at least opens up workarounds for the problem... but there obviously shouldn't need to be any.
______________
Hardware: AMD Ryzen 9 3900X/MSI MAG570 Tomahawk X570/Zotac Geforce GTX 1650 Super 4GB/32GB OLOy RAM
Software: Windows 10 Professional/Poser Pro 11/Photoshop/Postworkshop 3
ice-boy posted Wed, 12 August 2009 at 2:37 AM
Quote - IS:
Are you using GC shaders with IDL? I haven't tested extensively, but I think you really can't. The data that GC shaders reutrn is for how to make that luminance on a screen. For light measurement purposes, those numbers are way too high. That would cause over-exposure for sure. That's why linear rendering is so important.
With Poser 8 and IDL, dump GC shaders altogether. Use linear output only from shaders. Make sure all diffuse calculations throw less light than arrives (Diffuse_Value < 1). Use HSV Exponential Tone Mapping at 2.2 for the final adjustment (approximately) to sRGB color space.
if we dont use IDL and only normal IBL and AO we also shouldnt use GC on shaders?
bagginsbill posted Wed, 12 August 2009 at 7:53 AM
Ice-boy,
You already know the answer. Before IDL (before last week) we did not use IDL, only normal IBL and AO, and we used GC shaders.
If you are not using IDL, then the values produced by a shader are not used by lighting calculations so it's ok if the value is non-linear.
However, I take this into account in my use of reflections. I assume that everything in my scene is a GC shader, and producing an sRGB color. So I anti-GC what comes from a Reflect node before adding it to other things.
The problem with shader GC + IDL is that the output of a shader is not only used to color a pixel in our image. It is also used to decide how much light reaches other parts of the scene. Therefore, we must not lie about that, or the IDL calculation will be biased towards being too bright.
If only we could tell the IDL to do that, then we could use GC shaders even with IDL.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
IsaoShi posted Wed, 12 August 2009 at 8:12 AM
Quote - ... that's when IL washes out the AO and oversaturates the character.
Possibly you missed this point: using IDL does not 'wash out' the light-based AO, it switches it off completely. It's no surprise you can't see any AO in picture #3 - there is none.
I agree, picture #2 is superb.
"If I were a shadow, I know I wouldn't like to be half of
what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki
Murakami)
ice-boy posted Wed, 12 August 2009 at 11:34 AM
Quote - Ice-boy,
You already know the answer. Before IDL (before last week) we did not use IDL, only normal IBL and AO, and we used GC shaders.
If you are not using IDL, then the values produced by a shader are not used by lighting calculations so it's ok if the value is non-linear.
However, I take this into account in my use of reflections. I assume that everything in my scene is a GC shader, and producing an sRGB color. So I anti-GC what comes from a Reflect node before adding it to other things.
The problem with shader GC + IDL is that the output of a shader is not only used to color a pixel in our image. It is also used to decide how much light reaches other parts of the scene. Therefore, we must not lie about that, or the IDL calculation will be biased towards being too bright.
If only we could tell the IDL to do that, then we could use GC shaders even with IDL.
thanks.
so HVS tone mapping is not like GC. but i think you said it still pretty good.
do you think we should from now on use only tone mapping since its easier to use the same shaders all the time?
bagginsbill posted Wed, 12 August 2009 at 11:45 AM
Absolutely.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
Iuvenis_Scriptor posted Wed, 12 August 2009 at 11:51 AM
Quote - > Quote - ... that's when IL washes out the AO and oversaturates the character.
Possibly you missed this point: using IDL does not 'wash out' the light-based AO, it switches it off completely. It's no surprise you can't see any AO in picture #3 - there is none.
I agree, picture #2 is superb.
I suspected as much. Still, even if I applied material-based AO, #3 would still look a little too Oompa-Loompa-ish for my tastes. Further testing shows that the settings which produced #2 yield similar results on a consistent basis, so I think I'll stick with what works...at least for now.
As another example, here's a nude shot I did of V4 using only BB's Environment Sphere and one infinite light to simulate the sun.
In case anyone's interested, the shader that I used in all three test images and the gallery image can be recreated using this tutorial. The advice given on lighting doesn't apply to P8 when using IL (there's no need to change the Diffuse Strength of each non-IBL light), though, and I'll probably add a "P8 Update" page soon.
Thanks for your comments!
ice-boy posted Wed, 12 August 2009 at 12:35 PM
Quote - Absolutely.
my english is not good enouhg . so that i am 100% sure i will ask again :)
if we have poser 8 we dont need to use GC shaders anymore? because hsv tone mapping is good enough?
if true then would we have to change a lot from your VSS skin shader to make it more practical for tone mapping?
bagginsbill posted Wed, 12 August 2009 at 12:51 PM
You have it right, except the last part about VSS shaders.
On all, change the gamma to 1.0.
On the skin shader, change the SSS color to be a less strong red.
Done.
All the demos I showed for Poser 8 were done with Poser 8 HSVETM and VSS and those two small changes.
See:
http://poser8.smithmicro.com/gallery.html
Anything that says Bagginsbill or Ted Czotter is me.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
bagginsbill posted Wed, 12 August 2009 at 12:52 PM
All VSS.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
ice-boy posted Wed, 12 August 2009 at 1:16 PM
thanks. i will get poser 8 this week.
but to be honest on those renders the fake SSS from the shader looks very strange. i dont know if this is from the GI bouncing. for example on the body on the right. on the edge you can see a lot of red color. i think it makes it looks very fake.
ice-boy posted Wed, 12 August 2009 at 1:17 PM
Quote - You have it right, except the last part about VSS shaders.
On all, change the gamma to 1.0.
.
i think it would be better if we delete some nodes that we dont need. that way it would be easier to look at the nodes and do changes.
bagginsbill posted Wed, 12 August 2009 at 1:38 PM
Quote - thanks. i will get poser 8 this week.
but to be honest on those renders the fake SSS from the shader looks very strange. i dont know if this is from the GI bouncing. for example on the body on the right. on the edge you can see a lot of red color. i think it makes it looks very fake.
I applied the same settings to all, as it was only a test render. I was planning to adjust them better, as the amount of SSS really must be matched to each texture set. I hadn't yet posed them or clothed them how I planned. My plan was to do 16 figures, 8 Ryans and 8 Alysons, in many variations, all in one image. I wanted them dressed different ways, talking to each other, like at a party.
I sent that test render to SM, just to show them what I was up to. I did not know anything about the release date, and like most people I assumed it was a few weeks away. Turned out it was only 3 days away at the time! They liked the image enough to publish it, and before I knew what happened, Poser 8 was shipping!!!
So there's the back story.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
ice-boy posted Wed, 12 August 2009 at 1:46 PM
ok
we will tweak.
we like to tweak :)
bagginsbill posted Wed, 12 August 2009 at 3:22 PM
ice-boy:
Have a look here:
http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2779121
I demonstrated taking an existing studio portrait with a VSS character, starting with IBL and GC shaders.
I flipped on GI and got blown shaders. Too much light, and also shows the problem of using GC shaders with GI.
Then I disabled the output GC on the shaders, but I left the input anti-GC as always. I used P8 Exponential tone mapping (not HSV Exponential) to perform the final GC. It works the same as the output GC on our shaders. So we get the full benefit of anti-GC, linear shader calculations, linear GI values, and sRGB final pixel values. All with 5 minutes work on an existing scene.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
ice-boy posted Wed, 12 August 2009 at 3:41 PM
didnt you say some days ago that HSV is like GC? ?
p.s. i am now waiting for Carodan to show some renders. in my honest opinion carodan always has one of teh best lighting in hes renders. and not realistic. but artistic with emotion. i think renders with GI from him will blow my mind.
bagginsbill posted Wed, 12 August 2009 at 3:43 PM
Carodan is out of town on a job.
Yes I said HSV Exponential is like GC, but not the same as GC. There are two different tone mapping options; HSV Exponential versus Exponential. Exponential does the same Pow function as the final GC step. The thing that is missing is the incoming anti-GC, but we can do that in the shader.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
ice-boy posted Wed, 12 August 2009 at 3:55 PM
what will you always use? hsv exponential or just exponential?
bagginsbill posted Wed, 12 August 2009 at 4:01 PM
For little shader and lighting demos, with balls and boxes and simple shaders, HSV exponential.
For high quality renders, I'm now thinking Exponential + anti-GC shaders.
When I first saw the Exponential option and tested it, it seemed really dumb. Why do half the GC job? But then it dawned on me that I already had a solution for GC in Poser 7. All I have to do is just use half of it. Problem solved.
Renderosity forum reply notifications are wonky. If I read a follow-up in a thread, but I don't myself reply, then notifications no longer happen AT ALL on that thread. So if I seem to be ignoring a question, that's why. (Updated September 23, 2019)
ice-boy posted Wed, 12 August 2009 at 4:13 PM
aha.
thanks.
carodan posted Wed, 12 August 2009 at 8:11 PM
Quote - Carodan is out of town on a job.
I've been home for a while (after working on a very interesting non related art project ). Unfortunately I got side-tracked again so I'm pretty much lurking (frustrating!) until I can get back to a little Poser rendering.
I will say this much though, although there are still improvements to be made, the IDL looks to be working so much better than when I made my Ralphling render for the SM promos - things have moved quickly. 3 or 4 weeks ago the inverse square falloff on lights produced awful light and dark artifacts with IDL - that Ralphling scene literally looked like a 70's disco until I rendered with inverse linear.
(Edited to correct myself)
PoserPro2014(Sr4), Win7 x64, display units set to inches.
www.danielroseartnew.weebly.com
ice-boy posted Thu, 13 August 2009 at 11:48 AM
carodan:
i hope you will do a render with apollo with IDL
he he ;)