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EagleWing
01-17-2007, 03:57 PM
Here's a simple question...

imagine...You have a box in the scene and within this box you have a sphere.
therefore the sphere is not visible from any angle, it is inside the box completely.
If you take this object into Layout and render does the sphere get rendered.
therefore more meaningfuly, if you model a space ship, and you model all the insides too, corridores, doors, inanimate objects, bins, pencils on desks, whatever, if you view the ship from outside and you cannot see any of these things inside, you can only see the hull outside and maybe a few things inside windows, then you render does lightwave only "look" at and therefore render what can actually be seen by the camera?

Exception
01-17-2007, 05:05 PM
In general you can say: no it does not get rendered...
However there are situations where it does get rendered. It also depends a little on which camera you're using, the classic or the new one.

Of course this isn't true when you're using transparent materials, or some other raytracing shaders.
Also, it's not a 100% effective. It's what the KDtrees are for. very large planes in combination with much smaller polygons may misrender in the classic camera. I'm not quite sure if this will misrender in the new one too. The image will come out ok, but stuff will be rendered that isn't visible.

EagleWing
01-17-2007, 05:26 PM
I suppose that would depend on the scene. Let say for example we go with the space ship example, this could lead to a high number of polys and from the sounds of it from the pros using Perspective Camera is idea for large scenes and the Classic for use with general renderings otherwise.

So in that case what would be the outcome from using the Classic compared to the perspective camera?

Iain
01-18-2007, 03:37 AM
And what about the tree falling in the forest when no-one is around?

Oh, and the Pope-is he catholic?

oDDity
01-18-2007, 04:19 AM
Yes, sound waves are produced regardless if any human s there - we're not important, we've done this one before.
,,and no, the pope's not even a he for a start, but female. Anyone who's read Pratchetts 'Monsterous Regiment' will know what I'm talking about, the central idea of the book was allegorical, and entire catholic hierarchy is controlled my women masquerading as men, because it's the only way they could get in.

tonybliss
01-18-2007, 04:24 AM
Yes, sound waves are produced regardless if any human s there - we're not important, we've done this one before.
,,and no, the pope's not even a he for a start, but female. Anyone who's read Pratchetts 'Monsterous Regiment' will know what I'm talking about, the central idea of the book was allegorical, and entire catholic hierarchy is controlled my women masquerading as men, because it's the only way they could get in.


Now that was funny. That may explain alot :ohmy:

EagleWing
01-18-2007, 07:03 AM
And what about the tree falling in the forest when no-one is around?
Now how did I know that question would pop up? hahaha. :)

EagleWing
01-18-2007, 07:05 AM
Yes, sound waves are produced regardless if any human s there - we're not important, we've done this one before.
,,and no, the pope's not even a he for a start, but female. Anyone who's read Pratchetts 'Monsterous Regiment' will know what I'm talking about, the central idea of the book was allegorical, and entire catholic hierarchy is controlled my women masquerading as men, because it's the only way they could get in.

It's joan of arc all over again haha.
Perhaps someone should catch them out and ask them if they've got enough tampons. haha.

Surrealist.
01-18-2007, 09:55 AM
Here's a simple question...

imagine...You have a box in the scene and within this box you have a sphere.
therefore the sphere is not visible from any angle,...

Why is it you want to know this information?

EagleWing
01-18-2007, 10:10 AM
because i've got a transport ship in a space scene with corridores modeled and people walking around in it, and everything else in the corridores etc and i was wondering if when i render from an external shot if it would effect the render time if the camera can't see the tables inside or the corridores etc

Iain
01-18-2007, 10:16 AM
Yes, sound waves are produced regardless if any human s there - we're not important, we've done this one before.

Well, I once saw a tree fall on TV when no-one was around and there was no noise. I was looking through Ted Moult's window though.


entire catholic hierarchy is controlled my women masquerading as men, because it's the only way they could get in.

If women were in charge of the church, it would probably have some logical arguments so I can't accept that.

tribbles
01-18-2007, 11:51 AM
I think that any completely hidden polys will still have some computational time - it depends on how efficient the render is at eliminating them at an early stage (I wrote a renderer about 12 years ago - it wasn't terribly good, but I had fun writing it).

Surrealist.
01-18-2007, 12:12 PM
Another factor is RAM. Basically, if it not seen, don't put it into the scene. Start thinking of your animation set up like a moview set. You only need what you need for each shot. No need to put your camera into something if you can remove a wall and shoot from there. An exterior object can be a completely different set and object than the interior one. If you have a shot going from interior to exterior, only build the wall that has to have this transition for that shot. The rest of the object can be for interior/exterior purposes, depending on need.

If an enterior is visable through a window, ask yourself if an image map would do for that shot.

It is a real good practice to keep your scenes as simple, clean and lean as possible.

You can also split up a render, say if you have a moving shot where from frames 1-500 the interior is not visable and after that the crew and so on are visable then have a separate scene where the only difference is the inclusion or exclusion of objects. There is also a way to load up objects by a certain frame, so you could do it that way too. Probably at least another few ways to skin that cat as well.

But keep it simple and lean as possible.

EagleWing
01-18-2007, 12:52 PM
Another factor is RAM. Basically, if it not seen, don't put it into the scene. Start thinking of your animation set up like a moview set. You only need what you need for each shot. No need to put your camera into something if you can remove a wall and shoot from there. An exterior object can be a completely different set and object than the interior one. If you have a shot going from interior to exterior, only build the wall that has to have this transition for that shot. The rest of the object can be for interior/exterior purposes, depending on need.

If an enterior is visable through a window, ask yourself if an image map would do for that shot.

It is a real good practice to keep your scenes as simple, clean and lean as possible.

You can also split up a render, say if you have a moving shot where from frames 1-500 the interior is not visable and after that the crew and so on are visable then have a separate scene where the only difference is the inclusion or exclusion of objects. There is also a way to load up objects by a certain frame, so you could do it that way too. Probably at least another few ways to skin that cat as well.

But keep it simple and lean as possible.

Hmm interesting, having object only load after a certain scene. how is that done?

the thing i was thinking, how about having the interior on a seperate layer to teh interior then using object dissolve in object properties you could get it to disappear accordingly?

Surrealist.
01-18-2007, 01:32 PM
Well I may have not been clear on that.

First way: Just create two scenes from one master scene. The second is exactly the same only it has the objects you do or don't want in that part of the scene. So you render up to a point then stop. Then load up the other identical scene and begin rendering from a frame that is not changed from the previous - say just before the object begin to show - then render from there on.

Second way: And you have several options here, is in the Object Properties Pannel under the Geometry Tab, Object Replacement.

Page 188 in the PDF for lw9:


ObjectSequence

ObjectSequence replaces an object with another one at a certain frame of the animation. This replacement is like choosing Items > Replace With Object File except that it happens during the animation. ObjectSequence is to objects, what an image sequence is to images.
To perform an object replacement, you must have multiple objects with names that differ only by a three-digit number. For example, if you want to change between a series of box objects, you would name the first object box000.lwo. If you want that object replaced by a second object at frame 10, name the second object box010.lwo. This would be replaced by box027.lwo at frame 27, and so on. These objects donít need to have anything in common except their names.
To use ObjectSequence, load the first object normally. Then, select ObjectSequence as the Object Replacement plugin. All of the object files must be in the same subdirectory.

The only problem with object dissolve is you still have it in RAM though for some things it is definately an option.

EagleWing
01-18-2007, 01:40 PM
awesome thanks surrealist, very interesting i never knew about object sequence. i do now :) i will have a go at the first one first and fiddle with object sequence if i need to. thanks very much all for your help.

Surrealist.
01-18-2007, 03:01 PM
And one thing to kleep in mind about object sequence is the scene has to work with that object with available ram or the scene could hang. The more complex your scene gets the more ram useage becomes an issue. This is why 64 bit is such a good thing, it allows for more ram - if you have it. However, still good to be in the prectice of economy.

Good Luck. :)

EagleWing
01-18-2007, 03:30 PM
Thanks mate. :)

Lightwolf
01-18-2007, 04:20 PM
Actually, as a side note.
If you plan not to use a bigger part of your mesh, extract it from the main mesh and save it as a separate .lwo.
The reason being: Even if a layer is not visibly loaded into LW (-> hidden), it will still use up memory (because it is loaded, just not available). The reason for this is that otherwise LW could not save the .lwo with the hidden layer.

Cheers,
Mike

EagleWing
01-18-2007, 04:22 PM
good point, never thought about that thanks Lightwolf.

Surrealist.
01-18-2007, 08:49 PM
Actually thanks for that. It was something I have had a question about, so that clears it up.

EagleWing
01-19-2007, 05:59 AM
no problem, if you never ask you'll never know right? hehe.

will give it a go and let you know.