How do I stop these Light Leaks?
by James Brad Barnette · in pureLIGHT · 10/16/2009 (12:02 pm) · 5 replies
I was wondering what is the recommended way to stop these lighting leaks that I'm getting in PureLight?
Grated I did these at a low sample. "4" But are these going to show up in the bake at higher samplings? I would like to know before I waste a day doing it.
Grated I did these at a low sample. "4" But are these going to show up in the bake at higher samplings? I would like to know before I waste a day doing it.
About the author
#2
Also, bleed happens on lightmaps, that's why optimizing helps keeps space between the UV faces.
10/16/2009 (12:30 pm)
Is your mesh sealed/verts connected? Or are those arches just lying against a wall?Also, bleed happens on lightmaps, that's why optimizing helps keeps space between the UV faces.
#3
10/16/2009 (1:02 pm)
yeah I did optimize But I guess I should maybe break it up more and possible make the planes interpenetrate more.
#4
10/16/2009 (1:20 pm)
Quote:Faces should join, rather than interpenetrate.
planes interpenetrate more.
#5
The number of samples will not change the light bleeds - they will just get less noisy and more resolved, like the rest of the lightmap. Lightbleeds, as noted above, are caused by physical gaps or interpenetrating geometry; take a look at chapter 16 in the documentation:
http://www.purelighttech.com/documentation/
(also in the pureLIGHT help menu or in the start menu under the pureLIGHT install)
For you case here, it looks like that beam is resting against the wall - and the resolution / filtering of the lightmap is such that the crispest shadow possible spans the space, leaking out the other side.
You can mitigate this a few ways (all in the documentation, but this is the short form):
a) Cut those beams into the wall
b) Make the beam mesh 2 sided - half the problem now is that the underside of the beam is seeing through the backside of the beam mesh (meshes are 1 sided by default), thus the space under the beam is brightly lit. If the beam mesh was 2 sided, that space would be in shadow. You would then have a shadow bleed (darkness leaking out) but this often looks a lot more natural, especially with textures and such.
c) Increase the lightmap resolution for the wall and or decrease the filter sizes (see filtering in the documentation - this can get fairly advanced)
---
Looking at the screen shot, it also looks like you have a lightbleed at the ceiling. The usual lightbleed solutions apply, but a good trick of mine is to encase your scenes inside an inward facing opaque black box, except for the spots where you actually want sunlight entering in. The "correct" answer is to always have the geometry cleanly cut in, but in practice the solution is usually to mitigate or work around only the lightbleeds that actually become a problem.
I hope this helps!
10/16/2009 (1:56 pm)
Hey - The number of samples will not change the light bleeds - they will just get less noisy and more resolved, like the rest of the lightmap. Lightbleeds, as noted above, are caused by physical gaps or interpenetrating geometry; take a look at chapter 16 in the documentation:
http://www.purelighttech.com/documentation/
(also in the pureLIGHT help menu or in the start menu under the pureLIGHT install)
For you case here, it looks like that beam is resting against the wall - and the resolution / filtering of the lightmap is such that the crispest shadow possible spans the space, leaking out the other side.
You can mitigate this a few ways (all in the documentation, but this is the short form):
a) Cut those beams into the wall
b) Make the beam mesh 2 sided - half the problem now is that the underside of the beam is seeing through the backside of the beam mesh (meshes are 1 sided by default), thus the space under the beam is brightly lit. If the beam mesh was 2 sided, that space would be in shadow. You would then have a shadow bleed (darkness leaking out) but this often looks a lot more natural, especially with textures and such.
c) Increase the lightmap resolution for the wall and or decrease the filter sizes (see filtering in the documentation - this can get fairly advanced)
---
Looking at the screen shot, it also looks like you have a lightbleed at the ceiling. The usual lightbleed solutions apply, but a good trick of mine is to encase your scenes inside an inward facing opaque black box, except for the spots where you actually want sunlight entering in. The "correct" answer is to always have the geometry cleanly cut in, but in practice the solution is usually to mitigate or work around only the lightbleeds that actually become a problem.
I hope this helps!
Torque Owner James Brad Barnette
3Dmotif LLC