Render to Texture : edge padding is overbrighten

[KebabMakina]

Hello !
While baking an interior with Max Render to Texture, the "bleeding" pixels (of a wall for instance) seems to get the full exterior brightness (sun), resulting on some kind of light leaks.
This is a rough brute force try, it's not getting better if i push the quality :



I also have a problem with some boards on the wall...
Walls have a thickness.
I've pushed secondary ray bias to 0.001 and up.

Is there some magic parameter i have to tweak ?
Is there any workaround ?

Thanks for any advice.

[vlado]

You'll have to make the walls thicker, or increase the resolution of the baked texture. There is no other workaround I'm afraid.

Best regards,
Vlado

[KebabMakina]

Ok thanks vlado, i've spent more time into making a clean exterior geometry and it came better.

I've another question regarding GI algorithms and RTT.
I've read several times (included official tutorial) that Brute force must be used as first and secondary bounces because other algos would be camera dependant.

I must say i really struggle to get a decent result without 1 hours calculation for a 2048 map, and still a lot of noise, though there's no glossy, no specular...Very basic shaders.

Are LC and IM really to avoid ? Should i then use world sampling instead of screen ?
I ran some test, i must say, with a lot of leaks unless i really push high the settings, which lead me to almost same time as brute force.
Thanks for any advices on lightmap workflow.

[vlado]

Are LC and IM really to avoid?

The light cache with world scale might be useful, along with the "retrace" option. The irradiance map will probably lead to light leaks unless you use really high "max. rate".

Best regards,
Vlado

[KebabMakina]

ok thanks.
I'm not sure for the world scale tho.
The LC sampling looks homogeneous in screen scale, independently of my vraycam position, so i guess the render to texture is considered like some kind of super top camera.
So world scale or screen scale would do in this case, pretty much the same.