Author Topic: Wrong smooth on round surface  (Read 3553 times)

2015-09-30, 18:44:36

Alessandro

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Hi, I notice this, in max 2015 and 2016 x64, last corona build, there is a problem with smoothing.
Very basic scene, a teapot (and an edited cylinder) on a plane, corona material (or simply a color for 2015 rel.) and a corona sun light in 2016, a corona light (sphere) in 2015. You can see the result.
Is it me?
My Ducati or a render with Corona.....mmm, hard question!

2015-09-30, 18:56:34
Reply #1

Frood

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Never underestimate the power of a well placed level one spell.

2015-09-30, 20:01:50
Reply #2

Alessandro

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Yes. But I can't consider this as a low poly object. In real world (I mean when we are working, not having fun with a demo of our capability, no time limit...) we have to optimize out mesh, as you can see near the teapot there is the same object with a Lattice modifier, I repeat, this is not a low poly. This is a problem.
My Ducati or a render with Corona.....mmm, hard question!

2015-09-30, 20:58:21
Reply #3

Frood

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Yes. But I can't consider this as a low poly object.

Well - lets say it´s not highpoly ;)

This is a problem.

I don´t say it isn´t. In my opinion it really is.

Good Luck!


Never underestimate the power of a well placed level one spell.

2015-10-01, 11:23:59
Reply #4

Alessandro

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Frood, just to talk with you, to define the number of polygons needed to well render a surface I always consider the border, I mean the silhouette of the surface, when it seems to be continuous it's ok. The shader has to do the rest. I also have to consider the total amount of poly in the scene, to have a "usable" scene.
We can talk one live about the meaning of high poly, and of course if I'm rendering a single object of course I can exaggerate with polygons, but in a regular set, with a lot of objects, I have to consider everything. Just yesterday I was talk with a friend, his "render boys" have create an exterior scene to be animated, with so much polygons, and it takes about 1 hour per frame!!!! He was killing them....I've stopped him just in time! ;)
Btw, someone has moved this tread in Resolved bug, but sorry, IMHO it remains a bug.
Take care, and thanks for your support.

PS: I'm curious, how many poly has got the highpoly teapot in https://coronarenderer.freshdesk.com/support/solutions/articles/5000516258 ??...
My Ducati or a render with Corona.....mmm, hard question!

2015-10-01, 11:29:19
Reply #5

maru

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Technically this is not a bug, it comes from the way Corona works, and it is expected - this is how objects would look like in real life in similar lighting conditions. But indeed, it does not look good, and some other renderers were able to overcome this, so most probably this will have to be fixed some day. As far as I remember some time ago Ondra said this would be very hard to fix.

btw, this is known since some really really early versions of Corona

2015-10-01, 12:38:05
Reply #6

Alessandro

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Yes Maru, and actually this is not the first time I'm writing about this.
Again, actually it doesn't create so hungry problems during normal work.
But, as my experience in Max beta testing tell me, sometime we have to talk again about the same old problems, otherwise the developer team forget them ;)

And, if it has to be fixed some day, it means that it's a bug ;)

My Ducati or a render with Corona.....mmm, hard question!

2015-10-01, 14:01:48
Reply #7

maru

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And, if it has to be fixed some day, it means that it's a bug ;)

No. You can read about a lot of things that have to be fixed some day, but they are not bugs:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000516180

2015-10-01, 14:17:42
Reply #8

romullus

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Currently this is limitation. It is very hard (impossible?) to fix, but relatively easy to overcome. Luckily it doesn't occurs very frequently, and there's no neccessity to subdivide every single object in your scene. It would be nice that this limitation would be fixed if / when possible for sure, but it's not game stopper. We have to live with it for now.

BTW, almost every raytracer suffers from this by some degree, AFAIK.
I'm not Corona Team member. Everything i say, is my personal opinion only.
My Models | My Videos | My Pictures

2015-10-01, 15:18:46
Reply #9

Frood

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[...] with so much polygons, and it takes about 1 hour per frame!!!! He was killing them....I've stopped him just in time! ;)

Hmm usually shaders are much much more responsible for a slow scene, not the poly (triangle) count (If you consider 1h/frame to be very long). Glad to see you could calm him down btw.

but sorry, IMHO it remains a bug.


User:      BOO BUG!
Developer: System immanent behaviour which prevents me doing the nice stuff for ages.


Let´s call it flaw? ;) I had that problem once in the last dozen projects and it could be easily fixed. But of course all your points are eligible. It´s just not worth the effort at the moment I fear.

Good Luck!

Never underestimate the power of a well placed level one spell.

2015-10-01, 16:17:27
Reply #10

Alessandro

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Hmm usually shaders are much much more responsible for a slow scene, not the poly (triangle) count (If you consider 1h/frame to be very long). Glad to see you could calm him down btw.

They've got a large number of frame, you can't have 1hour for frame in a video production if you aren't prepare the new episode of Star Wars!! ;) There were a lot of unoptimized surface, unoptimized material and so on, I think in a video production you must concentrate your work on the camera and object movement and the light. Than a very good post. Becouse of the resolution itself of the video (low considering the normal production resolution of a still) and the time you can spend on a single particular, you can of course optimize everything.

Btw, the real reson of my starting post is that I love Corona renderer, and I want it to be perfect, not just the best ;)
My Ducati or a render with Corona.....mmm, hard question!