LuxCoreRender Forums

Hi, have two verys simple scenes, just a few polygons and a glass of whisky.
One scene is 3km big and the glass is rendered well, the other is 800m big and the glass renders dark.
If this is still a precision problem why the bigger scene renders well?

3km scene 800m scene Thanks for any help.

The glass is at origin in the "transparent" scene:

scene.objects.903860_1_0_0_0.transformation = 1 0 0 0 0 5.960464e-08 0.9999999 0 0 -0.9999999 5.960464e-08 0 -0.0654683 0.0806955 0.04439508 1

while is more than 155m away in the "dark" scene:

scene.objects.903860_68_0_0_0.transformation = 1 0 0 0 0 5.960464e-08 0.9999999 0 0 -0.9999999 5.960464e-08 0 155.682 53.4093 0.0443833 1

As explained in the past (the message quoted here => viewtopic.php?f=4&t=3829&p=31635#p31627), floating point resolution is lower and lower more distant you are from the origin: the intersection of the exist surface of the glass starts to be missed so the ray travel for an infinite amount of times inside the absorbing volume.

Maybe a solution could be to internally have an option to downscale the entire scene by a Factor of 10X
After a certain point. Shouldn't be Min/Max epsilon value because that will trigger a new compilation at
Each value change.

Thanks... big problem. How other rendering engines are resolving this problem?
In the meanwhile would we resolve the problem if we identify the "center" of the view and use it to translate the entire scene to a more reliable 0,0,0?


P.S.
Do Luxcore uses 32bit or 64bit precision?

P.S.
Do Luxcore uses 32bit or 64bit precision?

It is FP32 bits precision. And I don't think there is an engine rendering a FP64.

I see, thanks sharlybg. The origin translation option seems the solution adopted by game engines. If there is no smarter solution around we go for this one.