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TJ213
08-Oct-05, 19:24
how can I make blender render things faster? I'm rendering an animation, and at this rate, it will take 20 hours to render a 56 frame animation. :o :(

zdk1
08-Oct-05, 19:58
Well, I'm not an expert, but I can give a few pointers based on what I've come across.


raytracing: for animation, unless you really need it try to not use it. If thats really how long your's is taking, I imagine you have a lot of raytracing. going on. Some of it may be necessary, but I'm betting alot of it could be done without.

generally use z-buffer lamps over raytraced ones. Set the samples and shadowbuffer as low as possible but having it still look good. Similarly, turn the samples down on everything as low as you can get away with people not really noticing (lights, subsurf, raydepth, etc.)

Those are the things that seem to help the render times the most for me. Remember, your not lighting for a still shot, you have to render 25-30 frames\sec. adjust lighting complexity and render resolution accrodingly.

A search in the forum might yield more comprehesive tips, one in particular is rendering in passes, though thats a little more involved than turning down samples.

Trident
08-Oct-05, 20:05
how can I make blender render things faster? I'm rendering an animation, and at this rate, it will take 20 hours to render a 56 frame animation. :o :(

What type of scene this is exsactly? Do you use internal renderer or Yafray? What are your system specs? (And yes, MBlur+OSA 16 is sure way to making not so complex image (http://blending.hotbox.ru/Aurora.html) to render for 40 mins on 2 GHZ)

TJ213
08-Oct-05, 20:23
These are my render settings:
http://img346.imageshack.us/img346/8263/renderscreenshot4kd.png (http://imageshack.us)

and here is a screen shot of the area I'm rendering:
http://img346.imageshack.us/img346/1378/basewithtankatvandpelican0dq.jpg (http://imageshack.us)

I'm using a laptop, with a 2.8ghz P4 with HTT, WinXP Media Center 2005, 512MB DDR 400, and a 256MB ADI Mobility Radeon X600

SamAdam
08-Oct-05, 20:26
wow, there is your problem!

try turning off OSA or moving it to 5. The best way to do this is to figure out how to not use raytracing. This will speed it up the most. You may have to do some hackish/ non photo real stuff, but that is even the way the pros do it, excect they can just use a scanline renderer with dynamic raytracing. Which we could use in blender. Try rendering in a renderman compatible renderer if you want to give that a try.

TJ213
08-Oct-05, 20:37
okay, I'll try that (once I re-read you post 5 times to figure out what it says) :-|

Oh, and when I disabled ray tracing, the render window looked fine, but the outputed video was just black.

here are my lamp settings:
http://img335.imageshack.us/img335/7280/lamp0wh.png (http://imageshack.us)

Room335
08-Oct-05, 20:38
Try using the Blender Intel/AMD optimized version 2.37 optimized

You'll get 30 -40% increase in speed,

http://www.elysiun.com/forum/viewtopic.php?t=17626&highlight=intel+optimized

TJ213
08-Oct-05, 21:28
wow guys, thanks for all your help. I still haven't figured it out, but do you think distributed processing or something would help? I have a desktop (2.4Ghz HTT, 128MB Nvidia, 512MB DDR400) and another laptop (2.4Ghz P4M, 32MB Nvidia, 512MB RAM) all on 802.11.g

No OSA or RAY:
http://img313.imageshack.us/img313/6282/noosanoray5wt.jpg (http://imageshack.us)

No RAY:
http://img398.imageshack.us/img398/235/osanoray4gr.jpg (http://imageshack.us)

RAY and OSA enabled: (this one took forever)
http://img398.imageshack.us/img398/1446/osaandray6vj.jpg (http://imageshack.us)

TJ213
08-Oct-05, 22:03
Try using the Blender Intel/AMD optimized version 2.37 optimized

You'll get 30 -40% increase in speed,

http://www.elysiun.com/forum/viewtopic.php?t=17626&highlight=intel+optimized


it worked, kinda, I imported the scene, but when I rendered, by computer froze :(

zdk1
08-Oct-05, 22:06
I really don't think that raytraced lights in this case offer any advantage over z-buffered lamps. Try switching them to z-buffered lamps (this means you'll have to tweak the settings, clip-dist, fallof, samples, buffer-size, etc) but trust me its worth it. If you want any animation at all, avoid raytracing like the plague unless you really, really really, really, really, really, really, need it (which I don't think you do)

and don't use pure white for all the lamp colors, it makes everything look flat and dull, and generally less interesting.

TJ213
08-Oct-05, 22:09
okay, but....umm, how? could you give me on advice on how to do that? I'm still pretty new to blender, (I've been working with it for about 2 weeks) and I haven't even started editing lights yet. (other than duplicating the default lamp) could anyone help me on AIM?

(btw, you sig, lol) :D

zdk1
08-Oct-05, 22:45
The blender docs should be a good place to start. Here are some basics on z-buffered lamps though.

select the lamp you want to edit. In the in the lamp options, there should be a list of various lamp types. Right now, the only type that uses z-buffered shadows is the spotlight. click on this one. Now, in addition to ray-shadow, a buffer shadow option should appear, click it.

A whole bunch of options pop up. make sure the spotlight is pointed in the direction you want (grab/rotate it in the 3d view). set its distance and SpotSize (essentially radius) so that it covers everything you want it to.

Ok, the thing about z-buffer lamps is that you have to set clip-start and clip-end values. These tell it when and where it should be calculating shadows. Make sure everything you want to cast or be affected by shadows is within the clip-start and clip-end distance (its represented on screen as a line pointing out from the spotlight.

samples and Buffer-size are the other basic ones. Higher = better quality at the expense of render time. They really don't need to be set that high though. tweak until you're happy (note that you have the ability to tweak now since the renders should be much faster).

note: since spotlights only illuminate things in their cone, you need other lamp types for general illumination. standard lamps are ok, though i personally like hemi-lamps.



its a lot of stuff to mess with (color, fallof, bias, etc), but a quick search should net you some bettter tutorials that will get you set on your way.

oh, since you mentioned it, my sig is based on personal experience :o

TJ213
08-Oct-05, 23:02
wow, thanks a lot, I'm working with what you said, and the help from this community is great. I'll keep working with blender, and once I know more I'll try to help people.




oh, since you mentioned it, my sig is based on personal experience :o
(scary thoughts)


(note that you have the ability to tweak now since the renders should be much faster).

yes, no more 30 minute a frame render times.

btw, does anyone have any advice on animations? The only animation work I've done (before this animation, and a simple walking one) is in macromedia flash MX. I heard something about emptys to move a character? and I have absolutly no clue what NLA is.

TJ213
08-Oct-05, 23:11
hmmm.....I don't have any shadows, and the objects are in that cone thing.

http://img223.imageshack.us/img223/209/v2noshadow9gy.jpg (http://imageshack.us)


btw, how can I switch between cameras?

zdk1
08-Oct-05, 23:46
probably the objects aren't within the clip-start and clip end values. clip-start should be set to a low value, not far from the spotlight. clip-end should be set to just a little bit further than the furthest object in your scene. There should be a visual representation of the area inbetween shown by a line with dots on each end. basically, whatever lies on that line's path is included in shadow calculation. and a couple gimmes, make sure the buf-shadow option is on (with the lamp settings) and that the global shadow option is on (render settings).

As you noticed, only the stuff inside the cone gets lit. use other lamp types for diffuse, general lighting and spotlights for shadows. You can widen the spotlight to include more objects in the shadow, use multiple spotlights, etc. You can also make spotlights only cast shadows and no light.

just mess with each setting and see what happens.

In any case, here's a cool and useful resource,

http://download.blender.org/documentation/html/book1.html

screens are old but its still really helpful (read the lighting section, much clearer than anything I can write)

Modron
08-Oct-05, 23:55
you can also render faster by rendering directly from the python console, the only thing is, i forgot the command. z3rod knows it, and i'm sure it's listed in the blender/python docs somewhere.

TJ213
09-Oct-05, 00:16
okay, it turned out to be samples, and the bias values, but now when I run the video in Windows Media Player, its blank, but when I hit that play button it works?


btw, I need to put some bump maps onto my character. How would I go about doing that?

thank you again for all you help. :)


lol, Modron posted while I was writing my post, should I just PM z3rod about rendering from python (which I know nothing about, other than python is some sort of language or something that helps write plugins? (I want to figure out blender first))

Room335
09-Oct-05, 02:16
Blender Intel/AMD optimized freezing... read through the Intel optimized thread and see if someone else descibes the same problem. I'm running a P4 1.8 with an Nvida card. 512 RAM, no problems. Although these days I'm running the 2.38 CVS version with all of the new features on it.


As to NLA, Emptys, Armature Bones , Action window.

There's some really nice changes coming out from the CVS but since your new to Blender animation, I suggest you use 2.37 and read the tutorials on the manual, see the link above link in zdk1's response.

wah_tak
09-Oct-05, 05:16
okay, it turned out to be samples, and the bias values, but now when I run the video in Windows Media Player, its blank, but when I hit that play button it works?

Which codec are you using? it seems "AVI Jpeg" isn't usually supported by media players.

TJ213
09-Oct-05, 16:18
I was using AVI Jpeg, but that worked in the past, I guess I'll try AVI codec, and is there a way to get rid of those lines, that the manual says are there so it appears propperly on a TV?

TJ213
09-Oct-05, 18:43
Thank you all for your help, I finished my render:

Click here to watch 0001_0410 (http://media.putfile.com/0001_0410)

as you can see, I have absolutly no idea about how to do animation other than that thing in the begining of the blender manual, does anyone have any suggestions? I've heard of using a "empty" to move the character instead of dragging the skeleton, and I've also heard of "NLA" what are these?

Room335
09-Oct-05, 23:45
If you have a good understanding of the armature system then try these:

First:
http://argoslabs.com/~malefico/tutor/walking.html
teh this one next

Second:
http://argoslabs.com/~malefico/tutor/nla-en.html

Also you can go through the tutorials here
http://mmaigrot.free.fr/didac-blender/nla/eng/index.php