Water Render times

gradient · January 13, 2007, 06:48:43 PM

Just did my first water render test.....OUCH.....

http://www.renderosity.com/mod/gallery/index.php?image_id=1363782

This was 800x600 with a P4 2.2GHz machine...quality setting at 1...render time 69hrs 35 minutes!
The simple atmo took only a few minutes....then.....it rendered the subsurface terrain, then layered the water over the already rendered subsurface terrain....can't see why it has to waste time rendering the subsurface texture if there is no water transparency yet.....

Will · January 13, 2007, 06:54:00 PM

its probluably just in preperation for the future, and 69 hours of rendering times....wow just wow My max so far has been 11.8 of course surface renders take longer then orbital renders.

buchvecny · January 14, 2007, 12:00:57 AM

well i suggest everyone to NOT render water. The render times are obviously not optimized (yes water will take long even in final but not like this) and then the water doesnt really have any new functions excluding the 3D waves.

buzzzzz · January 14, 2007, 12:27:12 AM

Nice render Gradient! Just thinking that 60 hours is rather long for a 800x600 render, however the one I posted on my site was rendered @ 1280x960 and took 36 hours mostly because of the large quantity of cloud samples. 3.02 p4 with Hyper Threading using only 50% cpu. I have had TG 9.43 take 8 days to render water scenes so TG2 might not be as bad as some think. Gradient? I'm wondering if you have ray traced shadows checked in quality atmo settings and render settings. If so I found that to really add to render times and I don't know if it's always needed.

gradient · January 14, 2007, 01:16:38 AM

@Jay; Just checked my tgd...I didn't have ray tracing checked...so, methinks its just the darn water!!!
I'm glad I didn't have any clouds in it or the thing would still be cookin'...LOL!
It's the longest render I've ever done...had a few 0.9XX ones go around 40 or 50 hrs. I was just hoping that we wouldn't have a power failure...then I would have "lost" it....in more ways than one!

I think I'll stick to dry land till things get sorted out....

buzzzzz · January 14, 2007, 01:23:03 AM

Quote from: gradient on January 14, 2007, 01:16:38 AM
@Jay; Just checked my tgd...I didn't have ray tracing checked...so, methinks its just the darn water!!!
I'm glad I didn't have any clouds in it or the thing would still be cookin'...LOL!
It's the longest render I've ever done...had a few 0.9XX ones go around 40 or 50 hrs. I was just hoping that we wouldn't have a power failure...then I would have "lost" it....in more ways than one!

I think I'll stick to dry land till things get sorted out....

I'm thinking of rendering the land in 9.43, render a matching sky in TG2 and then blend the two together in photoshop. At least until I figure this fricking thing out! LOL

Hannes · January 14, 2007, 04:01:04 AM

There must be something wrong. Of course water takes a little longer, but that's way too much. You wrote "quality setting 1". Do you mean the detail setting in the render/quality tab? As far as I know there was mentioned in some earlier thread that this would increase the render time very much, but wouldn't give that plus of quality. I always leave it at 0.5.
I rendered the following picture with lots of samples in the clouds and used the "Full render" preset setting. The water is a little rough but that's a matter of the roughness setting I think. It took about one and a half hour to render.

Hannes

king_tiger_666 · January 14, 2007, 04:08:56 AM

sounds like some atmosphere or cloud samplings where very hi too....

Hannes · January 14, 2007, 04:57:01 AM

A simple test. It took 21 minutes to render.

jo · January 14, 2007, 07:25:03 AM

Hi,

Quote from: buzzzzz on January 14, 2007, 12:27:12 AM
3.02 p4 with Hyper Threading using only 50% cpu.

I'd just like to point out that a P4 with Hyper Threading is not quite the same as true dual core machine, or one with multiple independent processor chips. When a P4 HT says it's using 50% it's really using much nearer 100%. An HT chip has one full processor and a "virtual" processor. In a somewhat simplified description, this virtual processor works by putting instructions into the gaps between the instructions the full processor is working on. Chips like the P4 often have gaps in their instruction queue or pipeline. The maximum theoretical performance increase you can get with HT is maybe 20%, realistically probably somewhere around 10%, compared to theoretically 100% for a chip with two full processors like a dual core one.

Windows sees the HT chip as two separate processors, even though the bulk of the processing is always being done by the full processor and the virtual processor doesn't contribute nearly so much. Due to this a machine with an HT chip will say it's using 50% CPU when really that means it's using 100% CPU. When TG2 is multithreaded you might get a 10% increase in rendering speed, maybe, whereas a true multiprocessor machine could potentially get a 100% speedup ( though it might realistically be more like 50-60% ).

I need to write a FAQ for this

. I just thought I would mention this to let you know your machine is running much closer to 100% CPU use than 50%. My PC is a 3.0 GHz P4 HT machine too.

Regards,

Jo

gradient · January 14, 2007, 03:56:48 PM

@Hannes; My Render quality tab was set at 1 and antialiasing set at 3
@King Tiger 666; There were NO clouds...atmo was set at quality setting of 16 samples....

As I said I used a few shaders to get the berg texture...it rendered all that first including the entire full subsurface parts...then layered over the water. The actual rendering part of water overlay didn't take that long....the most time was taken to render the subsurface parts....But, I don't know if the two are linked in computation?

@Hannes...try a multi-shadered surface with water shader at render quality 1 setting to see what you get for render time....also, what processor are you using?

@Jo......you didn't touch on water render times.....

3DGuy · January 14, 2007, 04:42:22 PM

69 Hours. Phew, I guess you turned up some quality sliders? This image rendered in 20mins 5s.
Did this one quickly in about 5 minutes. I do wonder how you got the iceberg lit the way it is. Did you put in an additional lightsource?

ps. I did do autolevels in PS to get the colours a little less hazy.

gradient · January 14, 2007, 05:11:06 PM

@3Dguy; Quality sliders and shaders were set as indicated.....also, don't forget...from what I read here elsewhere, you have a high end machine too!
Regards lighting....yes you are correct...an additional lightsource was put in from the front. I have found this to be the best way to accentuate areas that would be in the shadows...similar to a "fill flash" in photo terminology.

BTW...many thanks for your pillar tgd and explanation!

Dark Fire · January 14, 2007, 05:28:05 PM

69 hours is ridiculously long. My computer could do top-quality renders involving water at hi-def quality in 10 to 20 minutes with the old Terragen. Now, with T2TP, it takes over an hour to render images with the 'Full Render' preset, which does not produce very large or particularly-high quality images (and it sometimes renders an image in which everything looks suspiciously purple or everything is white and nothing is visible - clearly errors!). Clearly a lot of bug fixing and optimisation needs to be done...

gradient · January 14, 2007, 07:13:23 PM

@Dark Fire; some difficult atmo settings used in combination with water often resulted in long render times with version 0.9XX as well....as Buzzzzz above indicated. You wouldn't get anything of "high-def quality" in 10 to 20 minutes with version 0.9XX.....
However, I do agree with you that some optimization clearly needs to be done (and Planetside had made this very clear at the outset)....I just hope that there can be adequate optimization accomplished, otherwise many of us will not be able to participate.....