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Hi JD,

there seems to be an issue with sunlight falling into a room, if there is an active emitter inside and the window pane is made of a glass material instead of AGS.
In case there is no Emitter the light shines into the room without a problem. As soon as there is an emitter in the room - the sun is lighting the room but no sunlight show up on the floor or walls in the room anymore.

Have you tried rendering the scene using a very small output resolution, in order to check whether the sun is rendering slowly, as opposed to actually not rendering? My guess would be that you will find the sun is just rendering more slowly, due to the cycles which are used to calculate the emitter's contribution.

Assuming that to be the case, I would guess it to be due to some optimization which is very scene-specific, so it would be good if you could send me the scene.

just test rendering the scene again to show this... also have to check because that issue came from another user on a german cinema forum (c4dnetwork.com). I'll upload my test together with his later on.

btw: to stress that again - as soon as the emitter is not in the scene anymore or not exported (muting it in ML is not enough) the sunlight can be seen from SL2...

maybe the same problem...

http://www.maxwellrender.com/forum/view ... 97&t=34182

you could try giving the emitters a ridiculously low value.. like 0,01 w to "manually" balance the calculation

is it a single emitter? if it is many of the same type, joining them up also helps if i remember correctly. but the approach for this is different depending on the software package you use.

my tries to show this issue.
I opened the double windows on the left to show there is sunshine in all tryouts.
As long as there are Emitters in the room (in this case 2 cylindrical lights, 60W each, same maxwell emitter material) there is no sunshine falling through the glass material windows. If the windows are made of AGS this is not an issue.

1st pic is glass WITHOUT Emitter, then comes the same with Emitter, SL20+, SL14 - both no sunshine, and the 4th pic shows the AGS sunshine with Emitter.

Normally I use AGS so this is not an issue for my daily work, but this is strange as Maxwell is expected to do this physically correct...

First, you should avoid the temptation to compare AGS and glass. While light which has come through glass has all passed through glass, light which has come through AGS has not passed through anything at all; remember, AGS is a mixture of reflective material and vacuum. And in this case, light which falls on the far wall has had to pass through not one, but through at least two panes of glass. I can't tell just looking at the images, whether the window panes are modeled realistically or not.

All that aside, if you look closely, you can see that it is indeed resolving. In particular, (a) you can see sunlight falling on the far edges of the inner sashes, and (b) in the second small image, you can see that the patch of sunlight falling on the far wall, while still dim, is nearly fully formed.

JDHill wrote:First, you should avoid the temptation to compare AGS and glass. While light which has come through glass has all passed through glass, light which has come through AGS has not passed through anything at all; remember, AGS is a mixture of reflective material and vacuum. And in this case, light which falls on the far wall has had to pass through not one, but through at least two panes of glass. I can't tell just looking at the images, whether the window panes are modeled realistically or not.

All that aside, if you look closely, you can see that it is indeed resolving. In particular, (a) you can see sunlight falling on the far edges of the inner sashes, and (b) in the second small image, you can see that the patch of sunlight falling on the far wall, while still dim, is nearly fully formed.

Even if the sunlight might start to appear at SL20 when using an emitter in the room - why is it already showing up from SL1 when using no emitter? The light has to travel through the same material. (It took 20 minutes to get that far - and what you see is render resolution...)
The HUGE difference is what bothers me...

AND mostly I just cannot wait to SL20+ when I use Maxwell on the only PC available to me atm - a core 2 duo 2.6ghz LAPTOP. So usually I use AGS and that solves most problems.

Just to be clear, I cannot offer any insight on how it works, I can only point out that your images show that it is working. I am mostly interested here in whether the plugin is exporting the scene correctly, and that appears to be the case.

sorry to have bothered you and taken some time off your precious little time to develop the next mindblowing plugin...
my sincere apologies.


keep up the good work!