Attached is a WIP that I have been piddling with for some time. Everything was normal until I added that lovely little bus-stop on the right. The bus-stop triples the render time. The anti-aliasing pass took 3 hours to get from 56% done to 57% done. There is some material complexity in the bus-stop, but nothing like volume or such render-time sinks. I am not sure what is going on here. I am very fond of the bus-stop and don't want to omit it. Has anyone ever had a render time triple with the addition of one element, and a small one at that? Peej

hey, it must be a bryce thing. If you look in my gallery there are two In Fall images. The first (yellow) took 20 hours to render. the second, I removed the sky, and atmosphere and it took 2 hours. Same stuff. I even added volumetric fog to the image after removing the sky and it didn't change the render time. I have a wine glass image on my site. The window, made of bryce objects did the same thing..from 30 min render to 2 hrs. Maybe it has to do with glass or the color yellow, I can't decide which.

Tirjasdyn
http://michellejnorton.com

Funny, but I've had problems with long render times in regards to yellow glass, too. I can switch to clear, or another color, but if I use yellow, it almost always doubles the render time.

Wow!! that looks like Fresno (no offense). antialiasing I'd bet. the proximity of the fence to the tree. good job peej.

oops forgot. don't forget to add the busstop route sign.

Just a simple test of the Yellow Glass theory, System is 800Mhz Duron W/512 Ram, Win98SE and geforce 3 AGP card: Rendered in preview window at 864x568 Doc size. All AA modes used Render was faster on Super AA with Yellow over clear glass NO AA clear glass no aa = 3 seconds clear glass no aa = 4 seconds Yellow glass no aa = 5 seconds NORMAL AA No glass normal aa = 6 seconds clear glass normal aa = 6 seconds Yellow glass normal aa = 7 seconds Super AA No glass SuperAA 16 rays per pix = 1.02 Mins clear glass SuperAA 16 rays per pix = 1.48 Mins Yellow glass SuperAA rays 16 per pix = 1.14 Mins Prem AA No glass Prem 16 rays per px all options (DOF set to Triangle) = 2.19 Mins clear glass Prem 16 rays per px all options (DOF set to Triangle) = 3.25 Mins Yellow glass Prem 16 rays per px all options (DOF set to Triangle) = 5.05 Mins

Should read: NO AA no glass no aa = 3 seconds clear glass no aa = 4 seconds Yellow glass no aa = 5 seconds

Maybe it's because the rays are passing through more than one layer of glass. I read in a thread ages ago that overlapping transparent+refractive textures cause massive increases in render time. You could try setting the refraction back to '100%' (no effect) and see if this improves things... or even remove the panes of glass along the back of the shelter?

I think the glass over glass thing is the killer. I know this isn't as nice, but try a station with glass only at the two short ends or probably more painful, one end and the back. manowr

Where did you get the models for the buildings? Are those bryce trees? Those eat processors ;)

Glass eats reneder time. (refraction, transparency, reflection etc) trees eat render time. (they are gits .. no other reason that i can think of)

I once did a transmapped object inside a complex glass object under water - did that take long! BTW that's an excellent pic.

I'd try to make the glass single sided. so there is only one reflective path to calculate. and take out some of the rough textures. and think about using the plane tool with a photo for the trees, that will give only one s/s item to calculate and cut down the hit rate. remember to watch the numbers that show up at the end of the render.( Ray attempts=80Quad Ray hits= 10 Trillion)

I would kill the glass or make sure casts shadows, accepts shadows, self shadows are off for the panes. Turn refraction to 0. Remove the posters or whatever they are from glass. Make sure that glass touches nothing else. Copy the material from one of cars (windows) if cars didn't add appreciably to render time. Or Hide bus stop for all renders and after final is done plop render window around bus stop. Export image and edit main render in graphic editor, pasting the plop rendered area into main render. I would lose glass and then add glass in PhotoShop

Absolutely wonderful picture! I am VERY impressed! I have found that I must be very careful with glass, especially when two panes of glass overlap. I see that your bus stop uses glass just like the "real thing". I'd suggest that you break up the glass panes (which is a pain!) to avoid the overlap. If this is a still image, you can get away with that, unless you change your camera angle. The second suggestion is to fuss with the glass materials. Some of them are really render hungry. One silly trick is to take the "simple" white material and fuss with it, adding transparency, specularity and reflection to it to "fake" the glass. That might help if you can live with the look. Of course, you know to make sure that the bump height is zero, and to turn off all settings that aren't needed. You might also check for reflection. If you can pull that lower, the render will speed up. Finally, and this may seem obvious, you aren't using the glass as a volume? Volumetric material is mega slow (at least i have found it so). Hope this helps give you ideas. Great picture! Good luck!