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n_e_gma
06-24-2005, 12:42 PM
Hi, hope someone can help.
I was rendering a simple terrain populated with ecosystem grass and a single tree placed by hand on the terrain. The problem is there are some visible jumps in the leafs distribution on the tree in the final rendered secuence (not using wind). The secuence (192 frames long - 640x480) took about 4-5 days to complete.

Is there a way i can render that tree alone with a proper oclusion mask (and proper GI, cause i also noticed that hidding the terrain from render also changes the way GI affects the tree) so that i can compose it with the terrain render in post?

I tried the mask options in the render multi pass options, but it only seems to work when both the terrain and the tree are visible to the render.

Id like to render just the tree so that i dont have to wait another 4-5 days rerendering everything all over again.

Wabe
06-27-2005, 11:34 AM
Easy to do. Click onto G-Buffer/Multipass options and select what you need!

n_e_gma
06-27-2005, 09:41 PM
Thank you Wabe, but i believe that the multipass option is for rendering stuff in "separate passes" like difuse, reflection and so on......i dont think that option actually does what i need (which is to render obejct A and object B each on a separate render job and then compose the image back together in post with the proper alpha).

Ill check it out anyway to see if i was mistaken

dlk30341
06-27-2005, 11:02 PM
Select the object(highlight it)....Now in your render settings, there is a place that says render selected object only....check this box...if you want the light as well...check that also. Hope this helps :)

n_e_gma
06-27-2005, 11:59 PM
Wabe, i cheked the multi pass options and it renders the alpha the way i need it for post, the only problem is i have to render the complete scene for that to work, so im not speeding up render time this way :(.

Thank you dlk30341, but i have no problem rendering just one object from my scene.

The problem is the resulting alpha i get when rendering each object alone. The alpha doesnt include the correct oclusion where the objects intersect.

here's an example:

http://www.hamercado.com/alphadilema.jpg

I only get the correct alpha i need for post if i render all the objects i one go with the "object mask" multipass option enabled.

But what i need to be able to do is render the objects one by one to speed up rendering and to fix a render i was doing, without having to render the whole scene again, where the tree in certain frames changed the distribution of its leafs for no reason at all, which makes it look shifty and messed up my render :(

I just did another render of my scene (first 48 frames-both objects visible to render- took 2 days to render) and the damn tree is still shifting its leafs in certain frames. Could this be a bug in Vue?

Can someone help me with the alpha dilema? :(

Wabe
06-29-2005, 07:30 AM
It is a little confusing to discuss this in two different threads the same time. So i posted in the other one what you have done here - only because i read the other one first.

However, the alpha dilemma. Is that what you want possible in other applications? I wonder. How can a program know what i want when i select render single objects? Wether i need them to do a collage in Photoshop and therefore need the full alpha mask for that or what you need, the cutted one that you need?

clodhopper
06-29-2005, 09:03 AM
I'm new to Vue, but i found this...i think this demo shows what you are talking about...if you wait till the end- its kinda slow. But in the breakdown shows individual object masks that are obstructed by forground objects like yer saying. I guess you have to render them together and then extract afterwards with the G-buffer? sorry if I'm wrong.

http://www.e-onsoftware.com/Support/ShowTutorial.php?t=Vue5Infinite/MultiLayer&cf=/Products/vue5infinite/?Page=4 (http://multi-layer%20rendering)

Wabe
06-29-2005, 10:32 AM
I havenīt seen this tutorial yet - who reads tutorials - but i think the point was NOT to render all objects together. To make the individual renders faster.

Which i canīt see how really, the more i think about.

n_e_gma
06-29-2005, 02:15 PM
but i think the point was NOT to render all objects together. To make the individual renders faster.

That's exactly what i need Wabe. To render each object on its own to speed up render. And again, to fix a render i was doing where the tree shifted the leafs in a few frames and messed up my render.

Is that what you want possible in other applications?
Yes is possible. But actually, come to think of it, in 3dsmax to get the alpha the way i need it i have to put a special "matte" material to the objects i dont want showing in the render. With this material the difusse is hidden from render but the alpha is actually render to oclude the objects behind it.

I guess, since vue render is so slow i wanted to trick it to render objects separatly to speed up and get the right alpha for post.

Ok ill stick to this tread only.

Thank you clodhopper. Ill check that link.

Wabe
06-29-2005, 02:34 PM
Yes is possible. But actually, come to think of it, in 3dsmax to get the alpha the way i need it i have to put a special "matte" material to the objects i dont want showing in the render. With this material the difusse is hidden from render but the alpha is actually render to oclude the objects behind it.

That is what i would call "manual". To use special materials to do what you want to. In fact you then render all objects always as well, only because of the simpler matte material a little faster.

Of course you can do that in every program and therefore in Vue too - create your own matte material (sheer white or black) and apply that then to the objects you don't want to see.

But what is with the reflections - in 3dsmax or Vue - when you render with radiosity? Doesn't it look different then because you don't have the same reflections then? Or how does any program know what material an object had before you attached the matte one to it?

n_e_gma
06-29-2005, 02:53 PM
That is true Wabe. The radiosity or GI looks diferent too if you hide objects from the render.

I guess ill just have to re render the whole animation again and hope the tree doesnt make another mess every other frame :(

Wabe
06-29-2005, 02:59 PM
That is true Wabe. The radiosity or GI looks diferent too if you hide objects from the render.

Let's take it that way, i always am... Ha ha ha!!

Good luck with the rerender and yes, hopefully all goes ok now. Just a thought, maybe you slightly change the animation a little bit at that areas where something went wrong with the leaves last time. Maybe that makes a difference then!

freakybusiness
06-30-2005, 02:10 AM
This is a really informative thread so far - thanks guys.

n_e_gma, you will only need to re-render the frames where the tree's leaves went crazy right? Or is that pointless because it would be a different 'simulation' altogether and no two renders are the same? I only have access to the Vue 5 Pro trial at the moment.

Either way, could I ask you to post the outcome of your re-render please? I am very interested in the reliability of Vue infinite for rendering animations and would like to hear from anyone who has (or better still has not) experienced inconsistencies from frame to frame when rendering an animation in Vue5 Infinite?

The video promos on the site really look awesome and the interface in the Pro trial is great, but I am applying for a govt grant to make a short animation/film and planned to import poser6 pz3's into vue infinite for the environments and to also use Vue as the network rendering solution - so it's ability to reliably render a scene consistently is a major requirement.

n_e_gma
06-30-2005, 05:31 AM
...
n_e_gma, you will only need to re-render the frames where the tree's leaves went crazy right? Or is that pointless because it would be a different 'simulation' altogether and no two renders are the same? ...
Yes, i tried rendering just those frames where there was this shift in the leafs of the tree, but the new rendered frames also shifted :( And the thing is i know for sure i dindt make any change at all to the scene in terms of wind or anything like that. The only thing i did was stop the render and resume it the next day cause i needed my PC to work on something else. I was also rendering with the render cow so i could see stuff like "last frame time"; dont know if that could have been the cause.

...
Either way, could I ask you to post the outcome of your re-render please? I am very interested in the reliability of Vue infinite for rendering animations and would like to hear from anyone who has (or better still has not) experienced inconsistencies from frame to frame when rendering an animation in Vue5 Infinite?...
Sure, no problem, i will post the final render when its finished. Im rendering right now another 40 frames so i can see right away if there is any shift in the leafs; so far the first 40's are ok. However, this time i did make sure wind was completly set off, cause i wasnt trying to simulate wind in the first place.

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