Unusual Render?

[jaf]

I started a long render last night and when I looked at the progress this morning, it looked unusual.  Could just be my lack of experience with TG2, but I thought I would post this to see what other's thought.

The lower part (A) was the normal first pass, but there was a black (empty?) band (B) across the whole width of the image.  Everything above the band was finished as usual and as I watched, it looked like the black area would render out fine (C & D).

Since I wasn't connected to the Internet and no other applications were running, I thought it was unusual.  The one big difference, and I'm guessing it is the reason, is instead of setting threading to min = 1, max = 1, I set it to min = 2, max = 4, just to see how long the render would take (it took 19 hours with one thread.)

I guess as I write this I'm seeing more clues.  There are two more models to the left of (B), so the black band or "no prepass" area starts there.  The whole image is 1200 pixels wide.

Anyway, is this a normal occurance and is multi threads the cause?  -- Jerry

[neuspadrin]

thats normal, happens on mine all the time.

for a) yes just normal first pass.

b) when it reaches a new row, it blacks out the entire row.

c/d) yep, renders through normally then after that.

just how it works, should be fine.

[jaf]

Thanks!  I guess it's a threading thing since it's the first time I saw it and I usually go with min/max 1/1.

The unusual part is it never displays the "pre-pass" dots -- it's like it's doing everything in that band is done in the final pass.

[neuspadrin]

Actually no, it does the entire prepass of dots, then once it starts that row it removes them. So as long as you catch it in the prepass youll still see the dots, once it starts rendering by rows youll see the row turn black as it starts on that row.

[jaf]

Your're right - I see that now.  I don't remember it working that way with a single thread, but maybe it did then too.