Author Topic: Glowing corners  (Read 4704 times)

2013-02-13, 15:03:30

ecximer

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Glowing corners in single-sided geometry.
When added Shell modifier glow disappears.
sorry for my english

2013-02-13, 15:05:13
Reply #1

maru

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Yes, I noticed this too. Flipping normals doesn't seem to change anything, so maybe it's path tracing related.

2013-02-13, 16:08:38
Reply #2

Ondra

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Looks like self-intersection/light leaks. Tesselating the wall polygons should help a little. Isn't the scene for example far from origin?
Rendering is magic.
Private scene uploader | How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2013-02-13, 20:33:58
Reply #3

ecximer

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No, the scene is located in the center.
Tessellate not try, but do not want to add extra polygons to an overloaded and so the scene.
sorry for my english

2013-02-13, 21:55:33
Reply #4

iliyang

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Looks like a too large ray offset epsilon to me, which makes rays escape the scene and hit the background. First, make sure that the triangles at the corner share the same vertices. Then try enlarging the two walls on the corner slightly so that they intersect each other. This should fix the problem.

2013-02-13, 22:51:18
Reply #5

Ondra

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Looks like a too large ray offset epsilon to me, which makes rays escape the scene and hit the background. First, make sure that the triangles at the corner share the same vertices. Then try enlarging the two walls on the corner slightly so that they intersect each other. This should fix the problem.

Or the epsilon is too small, and the secondary ray is classified as hitting the other triangle in the corner from outside the scene (so next ray is bounced into the environment). If I enlarge the epsilon, i get leaks, if I decrease it, i get self-intersections. Refer to this post for summary of my thoughs on the matter: http://corona-renderer.com/forum/index.php/topic,401.msg2874.html#msg2874
Rendering is magic.
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2013-02-14, 07:09:49
Reply #6

ecximer

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Ok. I understood that this error not an error is a feature. :)
sorry for my english

2013-02-14, 08:29:16
Reply #7

Ludvik Koutny

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Ok. I understood that this error not an error is a feature. :)

Yes, this is an error, but not easy to fix ;)

2013-03-22, 17:44:57
Reply #8

Stanislav_But

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i found same bug with curtain - helped only "shell" too.
But curtain was with self-intersection polygons and i thought that cause in bad modeling

sorry for bad english (c) ^^

2013-03-23, 01:34:20
Reply #9

Ondra

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http://corona-renderer.com/forum/index.php/topic,401.msg2874.html#msg2874

I'll take look at it, upload any scene that has such problem
Rendering is magic.
Private scene uploader | How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)

2013-03-23, 21:39:16
Reply #10

Stanislav_But

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two image with example and scene (max 2012 corona alpha 4) in attachment

2013-09-14, 18:55:45
Reply #11

Ondra

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Rendering is magic.
Private scene uploader | How to get minidumps for crashed/frozen 3ds Max | Sorry for short replies, brief responses = more time to develop Corona ;)