Chair animation for my dad, but with added extras...

Hello everyone. I am just finishing off a small animation of a chair that my father is designing (he’s an interior designer). Its all looking great as the camera flies around the chair to some Latin music, except when the chair lifts itself (its a gas lift) these great big splotches appear. They are not the typical Vray splotch problem though, they look as if they are a mapping coordinate problem. Like the texture is moving through the object, but it cant be that since all im using in the diffuse slot is a falloff map. Here is a picture of when it looks good and one where its got big dots on it .
Does anyone know what I could do to stop this happening? I have also posted a small movie (500kb) http://www.khachfe.com/vraydots.mov.

I would like to get it done by tomorrow night to give to him, so if anyone has any ideas, I would be very very appreciative.

Thanks,

Marc

hi
if you have moving parts, you will have to render frame by frame… looking great by the way

Hi thethule

in one of my last animations i had the same , well not really problem.

vray i-map didnt behave as expected,because i thougt, i could move objects, after i-map calculation, because imap would be stick on the surfaces of the objects.

Well as with your animation, i-map rather than a surface solution is a presentation of spheres filled with light, staying in space. so if you move your object, those spheres seem to stay at place.

as natty told, only frame by frame, or fakelight solutions will solve your problem, or maybe if you use an older 1.09 , you can use texturebaking to make a illuminaiton map for your design.

good luck, and a big renderfarm, because single frame computing is a real timeeater.

Tom

Hi tom and natty, thanks for the replies. But i dont understand. I am calculating an incremental imap, surely that is th same as doing a frame by frame. Im calculating the 330 frames at half res incremental imap then using that imap to render full res PAL. Are you saying that i would have to render the imap at the same time as rendering the image (i.e: full PAL imap)? Cuz otherwise i dont get it. Not being able to have objects move in your scene cant be right…Can you explain what you mean?
Anyway, i used the glitchy render to show him the work so far. Its still a WIP, but here it is so far, low imap and needs slightly higher aa. Its 6Mb.
http://www.khachfe.com/render.mpg (best to right click and save as)

Thanks,

Marc

hi thetule

first, nice animation, storry.

Well when you render an inremental i-map, you should use incremental ad to current frame, which forces vray, only to render those areas and details, that come new to the viewfield of your camera.

at last you get a god overal lighting for the animation you did. well , it sounds as if you did do this at each single frame, which costs much rendertime and also isnt nessesair for a flightthroug.

use incremental ad to single frame, and go to your rendersettings, to force vray to render only about each tenth frame. this is enough if you make such smooth and soft animations like you did. Here you moreover can use higher settings as you would in single immages, because you only render each tenth frame and also only one time the whole immage, because the follwing immages only compute the new areas that com new to your camara.

Well now your problem.

for your problem, you cant use incremental ad to current frame, because like in real world, moving objects change the whole light situation in each frame, you have. because of this reason, each frame for itself has to get a whole new light simulation. only way to get this isnt incremental ad to current frame, but " Single Frame".

The problem with this method is the stochastical analysis of the light situation. Because modern Rendersystems reach their speed only of analythical proximations of the real lightdistribution in the scene, immages would slightly change in light from frame to frame. this is usual, and depends on the quality settings you take for your rendering.

The lower your settings are, the more the frames flicker from frame to frame.

you only can solve this with very very high settings. And a way to do this is using for example lightmap for secoundary bounces, and direct computation for first bounce. Well of course is the most timeconsuming but at last most perfect way to get perfect results.

Another way was lightmapping for secoundary bounces (only with vray 1.4570), and l-map with very very high settings.

At last all of this take much rendertime.

the third aproach was to compute l-map only for objects that doesn´t move. All moving objects get excluded from i-map calculation, and get renderted with fake radiosity.

An example is the animaiton of a medicin machine i did some tima ago. (you also can find the fakelight script there)

here´s the link.

http://www.chaoticdimension.com/forums/phpBB2/viewtopic.php?t=7534&highlight=

Tom,

Thank you for the reply and kind words about my animation. I think i understand what you mean. I never used Vray to animate moving parts before, so i may be a bit slow to understand.
What you are saying is that the only way to get it to look right would be to render single frame imap with very high settings. Of course this would take a very very long time.
The other alternative you are talkign about is to render the room with incremental add to current, high setting, but only every 10 frames. Make sure that in object properties for the chair have receive GI and create GI turned OFF (is the chair hidden or visible?). Then create a fake light radiosity rig using your script, and have the lights light the chair only?

I think i got that right and i will try it out today. Please tell me if i am missing something. I watched your animations and they were very very nice. But im a bit confused by when you say you turned OFF all animated objects for the flythrough calculation. What do you mean by OFF? Do you hide the objects? Or do you just mean turn their GI OFF?

Thank you again for taking the tmie to explain this to me.

Regards,

Marc

hi thethule

well i turned all animated objects of means for precalculation i made them invisible.

after precalculation for the not moving objects, i made them visible again, but also turned of for them receive and cast Gi in the vray object settings . If i didnt, they still received some kind of gi looking nearly the same as your artefacts. this leaded me to the statement, that i-map in vray rather seems to be lighted volumes in space, than a surface solutionfor light.

After this step i used the fakelight setup that at last worked well.

Good luck with your animation .

Tom

Hey !
i see the inspiration !!! BUF commercial for IKEA…also same music

by the way this spot (from BUF) is just GREAT !
the remix from you is nice too but less impressive…it nice to follow the master anyway ! ;}

Tom,

Thanks again for the reply. I understood it all now. I will try it this week and post the result.

Olivier,
Yes, thats exactly where i got the inspiration from. I love that IKEA spot. I wanted to do something fun like it. I know its not nearly as good, but seeing as i had $0 budget and did it after work in my spare time… It was really just an idea to present to him. He liked my initial concept so we are going to go ahead and finish the animation. I think we should change the music as its very recongniseable from the IKEA spot, but we’ll see. I’ll post the final result here. Thanks for looking.

Regards,

Marc