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Hieron
09-01-2009, 01:09 PM
Grass has been my nemesis for a while and I had some serious issues with it. When I saw the thread about Autograss for Max I supposed it was time for another go at it, using the instancing plugin from Happy Digital. I need grass :P

End result:

http://img268.imageshack.us/img268/2538/grasscopy4.jpg

Rendertime for 720p: +- 7 minutes

Attached is a movie to show that it holds up in animation and the scene + models to render it. Did not add 2 textures I was unsure about regarding the rights.


It is basically the tutorial as on the HDI site, but with GI and weightmapping on each leaf and the ground to force some more depth in. And 2 extra objects to get a bit of clovers and flowers :P

Then add about 8 hours of tweaking, rendering and testing and I got the above. I'm pretty sure that those objects and settings can now be used pretty well on other jobs without taking the 8 hours again to set it up.

The image is perhaps not the best know to mankind regarding grass, but it is good enough so that I know I can use it in prod. and finally overcome my grass issues :)

Hope you find a gooduse for it, and if you can improve the look/renderspeed I'd be very gratefull if you pass back the improvements.


ps: The movie has DoF and slight MB done in post. More importantly it has "Neat Video"plugin applied to it, to do temporal blurring on the grass in the distance. Without that it is almost impossible to get rid of sampling issues when using a few pixels to visualize zillions of poly's.

archijam
09-01-2009, 01:33 PM
:thumbsup: nice work, and a great share ...

Cheers!

Tobian
09-01-2009, 01:41 PM
Just wish I had HDinstance to actually play with that. Absolutely stunning!

Larry_g1s
09-01-2009, 02:18 PM
Thanks for sharing Hieron, really great work.

Brian_7
09-01-2009, 06:43 PM
This may sound like a "noob" type of question but, how many types of grass blades did you model? I know the premise of HDI but, your grass looks SO REAL!!!

Brian

adk
09-01-2009, 08:22 PM
... great grass and a great share Hieron. Thanks a bunch :thumbsup:

Played around with this and works like a treat & looks fantastic. Not sure you could actually speed it up too much (it looks quite optimised to me), as I'm not much of an authority on AA / GI optimisation. Only thing of note is the daisy flowers using transparency instead of clip maps. On a few it seems fine but if you have a lot of these it would slow down considerably from my experience.

I was actually going to post a few questions on the related topic of sampling / AA issues on scenes such as these where you have a lot of detail / polys squeezed into a few pixels in the distance & how to best handle such issues. Would be great if you could setup AA based on distance to camera but alas I think I dream too much. I wonder how others deal with this in animations where such heavy blurring might not be possible because of the need to preserve those details ? Any tips / hints would be greatly appreciated.

Brian_7 - there seems to be only one blade of grass that's randomly cloned & scaled into a patch of grass of about 250 blades ... this is the patch that's then cloned by HDI.

geo_n
09-01-2009, 08:35 PM
Thanks for the scene. It looks great!
How come your q6600 renders it in 7 min and it rendered in mine in 12min? Did yo overclock?:)
Also what was the workaround with the weightmaps? Never encountered that.

AdamAvenali
09-01-2009, 09:14 PM
i think i may have broken the scene :D haha

i downloaded your file and then opened it and hit F9. my GI time was 16 min and my render is currently at 46 min and is only at 10%. i am on a Q6600. could it be that i told it to ignore the missing images when opening the file?

praa
09-01-2009, 11:23 PM
for the speed issues...

be sure to use HD Instance 207 and not 206

geo_n
09-02-2009, 12:00 AM
for the speed issues...

be sure to use HD Instance 207 and not 206

yep used 2.07. just hit f9.:D

Hieron
09-02-2009, 03:56 AM
Hey guys thanks a bunch! :)

Yes, make sure to have the just new 2.0.7 version!


i think i may have broken the scene :D haha

i downloaded your file and then opened it and hit F9. my GI time was 16 min and my render is currently at 46 min and is only at 10%. i am on a Q6600. could it be that i told it to ignore the missing images when opening the file?

Probably the version issue, the files should not matter at all...


Thanks for the scene. It looks great!
How come your q6600 renders it in 7 min and it rendered in mine in 12min? Did yo overclock?:)
Also what was the workaround with the weightmaps? Never encountered that.

On the rendertime: my sig is not correct anymore, I have a i7 920 now as my main which is not overclocked btw. My previous Q6700 was overclocked to 3.4 ghz and would probably be slightly faster (not sure, these i7's sure are nice). The weightmap problem is that if you use more than 1 instancing layer in HDI and on top you use weightmaps to place them, they get messed up. The solution is to just clone the groundplane (make them invisible) and do 1 layer per clone instead of all on 1 groundplane. Graham seems to know this issue and will probably be able to fix it real soon. In the meantime doing it like this will work fine.



... great grass and a great share Hieron. Thanks a bunch :thumbsup:

Played around with this and works like a treat & looks fantastic. Not sure you could actually speed it up too much (it looks quite optimised to me), as I'm not much of an authority on AA / GI optimisation. Only thing of note is the daisy flowers using transparency instead of clip maps. On a few it seems fine but if you have a lot of these it would slow down considerably from my experience.

I was actually going to post a few questions on the related topic of sampling / AA issues on scenes such as these where you have a lot of detail / polys squeezed into a few pixels in the distance & how to best handle such issues. Would be great if you could setup AA based on distance to camera but alas I think I dream too much. I wonder how others deal with this in animations where such heavy blurring might not be possible because of the need to preserve those details ? Any tips / hints would be greatly appreciated.


On the transparancy: I believe that HDI does not see it if I use clipmaps on the object that will get instanced. I tried at least and moved to transparancy right away. If HDI does see clipmaps I'd switch it..

On the blurring: details in the distance are hard to preserve with so little pixels to show them I guess.. making them smooth is surely an issue though.. something MB did not fix at all. Therefore the NeatVideo plugin, it blurs in time (can do spatial too) and thus takes out the jittering.


It is just 1 blade of grass indeed, with a weightmap over it's length. I tried using HDI first to just clone the 1 blade, but it keeps crashing if I fill in a instance per meter of 1000000 :P (which is the *only* time I encountered any issue such as a crash or so, when filling in a bizarro number :))

So I did a "random point cloud" in modeler, scaled to 0 in y and used Point Clone on the blade to these points. That patch can then be used by HDI just fine and probably works better too. This is according to the tutorial btw.


The shot can probably be improved speedwise, since I noticed that the grass is a bit crowded when the weightmap on the ground is 100%. Dropping the 12 per meter to 8 or so should still work, but the area where weightmapping varies between clovers and grass then needs some attention. Since the animation is smooth, perhaps the GI settings can be lowered too.

I dropped this into a current project and under 1 minute I had grass working in it. Sure needs tweaking etc, but it copies over easily. Only issue is that the general GI settings govern the HDI. And then you have to set the object properties to tweak it for everything else in the scene.. doable though.


ps: the animation does some odd glitches (vague movement of the cube for instance), it is due to the DoF plugin I think, it sure is not in the render.

JeffrySG
09-02-2009, 06:55 AM
Just wish I had HDinstance to actually play with that. Absolutely stunning!

:agree:

AdamAvenali
09-02-2009, 07:04 AM
Probably the version issue, the files should not matter at all...

thanks, i will check it out! :thumbsup:

dmack
09-02-2009, 09:55 AM
So what are the changes from 2.0.6 to 2.0.7? There needs to be an update .txt with these...

Hieron
09-02-2009, 02:00 PM
Just bugfixes I guess.. no clue about the changes.

ps: Clip mask does work, so removing transparancy from the flowers to clip mask makes it a very small bit faster.

AdamAvenali
09-02-2009, 03:47 PM
so i think my problem may be the fact that i am running version 1.7.1 :D

adk
09-02-2009, 05:00 PM
ps: Clip mask does work, so removing transparancy from the flowers to clip mask makes it a very small bit faster.

.. seems you have it sorted as I was just about to say ... "It's always worked for me" :thumbsup:

Hieron
09-03-2009, 02:05 AM
.. seems you have it sorted as I was just about to say ... "It's always worked for me" :thumbsup:

heh yeah, thanks for that one :)
No clue how I overlooked it...

:thumbsup:

fyffe
09-03-2009, 11:36 PM
it keeps crashing if I fill in a instance per meter of 1000000 :P

Woah, that should *not* happen. 8~ Can you send me a scene?

Larry_g1s
09-04-2009, 12:38 AM
Graham...Hieron's example needs to be on your site. ;) I'm very impressed.

Hieron
09-04-2009, 07:02 AM
Woah, that should *not* happen. 8~ Can you send me a scene?

Nope.. can't reproduce it anymore.. it's the first thing I tried (silly thing to try too, making a patch of grass is nicer anyway). It renders fine now and it doesn't crash anymore whatever I try. Perhaps I had some vague combo of things then, many things changed since in the scene.

Even put it up all the way to 1.000.000 instances per meter. Thus have 1*10^16 instances in the scene and it still tries to render (needless to say it doesn't get very far soon :)...)

Hmm sorry about that then... no clue what the reason was..

adk
09-15-2009, 01:14 AM
On the blurring: details in the distance are hard to preserve with so little pixels to show them I guess.. making them smooth is surely an issue though.. something MB did not fix at all. Therefore the NeatVideo plugin, it blurs in time (can do spatial too) and thus takes out the jittering.

I've been playing around with NeatVideo following your suggestion and must say (from my limited time with it so far) it pretty much rocks. Used it on some very very ugly (one AA pass) foliage tests straight out of LW that flicker like mad obviously. With this plug however that flicker fest is considerably better. Cheers for the heads up on that little gem :thumbsup:

Now I need to come to grips with how to get proper profiles / settings for "foliage noise" :) any tips there ?
I feel like I wasted days testing AA/AS/OS/render size for this particular issue when this (most likely) could have solved my problems in 1/10 of that time

Hieron
09-15-2009, 02:06 AM
A valued friend (:)) pointed me towards the considerable stochastic noise in my renders.. It does a great job at removing that. Some things you just can't get rid of by AA (like dense foliage) and this will smoothen it out over time. It is an especial perfect match with grass renders etc.

Larry_g1s
09-15-2009, 09:34 AM
I've been playing around with NeatVideo following your suggestion and must say (from my limited time with it so far) it pretty much rocks. Used it on some very very ugly (one AA pass) foliage tests straight out of LW that flicker like mad obviously. With this plug however that flicker fest is considerably better. Cheers for the heads up on that little gem :thumbsup:

Now I need to come to grips with how to get proper profiles / settings for "foliage noise" :) any tips there ?
I feel like I wasted days testing AA/AS/OS/render size for this particular issue when this (most likely) could have solved my problems in 1/10 of that timeNeatVideo huh, looks great from their site. Thanks for the heads up!

erikals
09-15-2009, 02:27 PM
hm, yeah :)
http://www.neatvideo.com/examples.html

Hieron
09-15-2009, 03:27 PM
Can honestly say that it is worth every penny.

A sort of similar plugin by Revisionfx:
http://www.revisionfx.com/products/denoise/gallery/

Has a fancier website for sure and a specific 3D render example. But I prefer Neatvideo, it is sort of essentially the same but NV has better options and tweakability imho. Cheaper too. Both are recommended if you don't have it though.

Something like that is a must with high density stuff like grass.. no AA will even smoothen out 1 pixel trying to capture thousands of grass blades....

erikals
09-15-2009, 04:34 PM
this might be something to consider too,
http://www.revisionfx.com/products/rsmb/

adk
09-15-2009, 04:59 PM
this might be something to consider too,
http://www.revisionfx.com/products/rsmb/

Cheers erikals, will have to test that one as well as soon as I get a chance. The combination of both these might be extremely handy :thumbsup:

erikals
09-15-2009, 05:55 PM
absolutely, combine that with LW's rocket fast PRMBlur, and you should get pretty decent rendertimes :)

adk
09-16-2009, 12:39 AM
... I'm quite amazed how well both these things actually work. We're talking extremely noisy/flickery tree fly by with no AA what so ever. Everything in the foreground & background fizzles like crazy. Afterwards ... well I'd almost say "to hell with AA and PRMB" :D but I realise it's horses for courses and this would not work for every job one gets.

:thumbsup::thumbsup::thumbsup: cheers guys

erikals
09-16-2009, 01:06 AM
just remember, it will never smooth the outer edges of objects, only AA can do that,
so you definitely need some amount of AA...

adk
09-16-2009, 01:25 AM
just remember, it will never smooth the outer edges of objects, only AA can do that,
so you definitely need some amount of AA...

:thumbsup: yeah I'm sure they have their limitations (NeatVideo seems to introduce very slight artefacts in some cases) so I plan to do a lot more testing as to when these would be big time savers in the sorts of things I plan to use them in. It's the dreaded foliage pixel fizz, that no amount of time reasonable AA / AS / OS settings (rendering at x4 seems out of the question for now) that I'm looking to battle with. So far tho results seem extremely promising :thumbsup:

erikals
09-16-2009, 01:33 AM
very true, http://www.revisionfx.com/products/rsmb is one of my favorites :)

Cageman
09-21-2009, 02:19 PM
HD Instance just got onto my "things to buy" list!

:)

Larry_g1s
09-21-2009, 02:28 PM
very true, http://www.revisionfx.com/products/rsmb is one of my favorites :)Got 404'd

Mr Rid
09-21-2009, 07:43 PM
just remember, it will never smooth the outer edges of objects, only AA can do that,
so you definitely need some amount of AA...

There are some post cheats that dont replace proper AA and moblur. But a sobel filter can make a quick luminosity mask that allows isolation of edges to apply post-blurring. This examples is zoomed 300%
77559

This moblur cheat only works on the outside of an object with an alpha, but it recently saved me a huge amount of render time for several elements that were moving rapidly thru frame and I needed to render out fast.

I rendered a quick 12-pass version. Then it was easy to make a mask in comp that excluded the white and black parts of the alpha, allowing me to post-blur only the steppy moblur area. This took about 4 seconds per frame in comp as opposed to several more minutes per frame in 3D. The bronze colored part is the CG object, comped over a BG plate-
77558

adk
09-21-2009, 08:30 PM
There are some post cheats that dont replace proper AA and moblur. But a sobel filter can make a quick luminosity mask that allows isolation of edges to apply post-blurring. This examples is zoomed 300%
77559

This moblur cheat only works on the outside of an object with an alpha, but it recently saved me a huge amount of render time for several elements that were moving rapidly thru frame and I needed to render out fast.

I rendered a quick 12-pass version. Then it was easy to make a mask that excluded the white and black parts of the alpha, allowing me to post-blur only the steppy moblur area. This took about 4 seconds per frame in comp as opposed to several more minutes per frame in 3D. The bronze colored part is the CG object, comped over a BG plate-
77558

Nice work Mr Rid & thanks for another great tip ... now off to play with this in Fusion :thumbsup:

erikals
09-22-2009, 12:07 AM
There are some post cheats that dont replace proper AA and moblur. But a sobel filter can make a quick luminosity mask that allows isolation of edges to apply post-blurring....

interestingly, you could combine it with this technique...
http://www.newtek.com/forums/showpost.php?p=925895&postcount=327