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oneiric413
06-03-2005, 10:20 AM
Can someone please tell me why this is happening. It's a rocket moving away from the origin (0,0,0). As it moves farther and farther away its gets more and more distorted. Is there a option in Layout to prevent this? I also have a really large earth object in the scene. Does LW not like large objects?


HELP PLEASE!!!

mattclary
06-03-2005, 10:58 AM
By chance are you using any texture deplacements?

-NG-
06-03-2005, 11:07 AM
Does it show up in the final render? do you have any deformers on it?what is your video card? Check the near clipping distance in the options panel.

Dodgy
06-03-2005, 11:11 AM
It could be an accuracy problem. If your grid size is too small or the planet is very big in comparison to the rocket, and the object is going to far away, LW might not be able to calculate the object accurately (it'll only have so many digits of precision).

The best thing to do is fake the scale of your planet (most space renders do this and get away with it.) so it's a lot smaller in comparison to your rocket.

mattclary
06-03-2005, 11:17 AM
It could be an accuracy problem. If your grid size is too small or the planet is very big in comparison to the rocket, and the object is going to far away, LW might not be able to calculate the object accurately (it'll only have so many digits of precision).

The best thing to do is fake the scale of your planet (most space renders do this and get away with it.) so it's a lot smaller in comparison to your rocket.

This is one of the advantages 64bit LW will bring if I remeber correctly.

oneiric413
06-03-2005, 03:09 PM
Thanks for all of the replys.


There are no texture displacements, It does show up in the final render. My graphics card is a NVIDIA GeForce FX 5200. I've never had another problem with it before. No deformers on the objects either. I have adjusted the near clip distance but doesnt make any better. which way should I go bigger or smaller?

I should point out also that it is fine near the starting position of (0,0,0) but gets worse and worse as you get further away. The rotation handles, size handles, etc all get worse as well when you move away. They distort like crazy!

I think Dodgy may have a good idea. The planet is VERY big to the rocket. It actually is 1/100 scale of a real sized earth and a 25m rocket. Therefore the rocket is EXTREMELY small in comparison to the earth. But in my animation I need the scale to be correct. Is there anyway to solve this?

How do I fake the scale of the planet? At most you will only be able to see a little less than half of the earth in the whole animation.

LW64 take care of this?? Maybe a different program (3DS or Maya)??

Thanks for all the help!

Captain Obvious
06-03-2005, 04:21 PM
This is one of the advantages 64bit LW will bring if I remeber correctly.
I'm not sure, but it doesn't make sense that it should. Lightwave has been using 64-bit floats for ages now, since all Pentiums and PowerPC processors can do 64-bit floating point math. The 64-bit version of Lightwave doesn't allow higher precision, at least not because of the 64-bittiness.


oneiric, you could try moving the planet away from origo. So instead of having the spaceship at, say, {10000000,0,0} and the planet at {0,0,0}, you'd have the spaceship at {5000000,0,0} and the planet at {-5000000,0,0}. That might help.

Or you could even have the spaceship constantly at origo and animate the planet, camera and environment (if you have one) to make it look like it's the ship that moves. Since the planet is a much simpler shape, it might not get as messed up.

oneiric413
06-06-2005, 07:20 AM
Is there anybody else that knows whats going on here? Here is another pic. Notice that not only is the object distored, the rotation handles are also.

The other thing is that my postion numbers are not crazy big. The last frame in my animation is only at (-1.3046 km, 962.4745 m, -217.5862m). By this point you can't even tell what the object is. But, those numbers seem reasonable for LW to handle, right?

Please help me!

THanks!

UnCommonGrafx
06-06-2005, 07:52 AM
What else is in the scene?
If there is anything else in the scene, that is not next to or near this object, then the error is a math one.

The numbers are crazy, yes. ;) Deuce provided a great explanation somewhere in the ether that is the net... To sum it up, the math can't be extremely precise when the numbers are greatly disparate. That is to say, a planet and a rock on said planet would give you the results you seem to have were you to try to go from the rock to a full of the planet. Not enough mathematical 'space' for this kind of scene.

mattclary
06-06-2005, 07:53 AM
Have you contacted tech support yet?

oneiric413
06-06-2005, 08:25 AM
What else is in the scene?
If there is anything else in the scene, that is not next to or near this object, then the error is a math one.

The numbers are crazy, yes. ;) Deuce provided a great explanation somewhere in the ether that is the net... To sum it up, the math can't be extremely precise when the numbers are greatly disparate. That is to say, a planet and a rock on said planet would give you the results you seem to have were you to try to go from the rock to a full of the planet. Not enough mathematical 'space' for this kind of scene.

There is a large earth object in the scene. However, without this earth object, the rocket starts to distort very slighty but not even close to the degree it does with the earth object in the scene.

LW goes to Mm so, I figured 1km is not so bad...


Deuce provided a great explanation somewhere in the ether that is the net...

What?


What program has enough mathematical space? Maya, 3DS, etc...???


Have you contacted tech support yet?

no, not yet. I will try though. Thanks!

UnCommonGrafx
06-06-2005, 08:30 AM
Actually, they all have this issue as it's a built-in side effect of fp math and the 32bit operating systems we are so hot to throw out. ;)

64bit boxes should help this; at least to the next limit.

oneiric413
06-06-2005, 08:35 AM
Actually, they all have this issue as it's a built-in side effect of fp math and the 32bit operating systems we are so hot to throw out. ;)

64bit boxes should help this; at least to the next limit.


What is fp math?

mattclary
06-06-2005, 08:36 AM
floating point

SplineGod
06-06-2005, 11:23 AM
This problem comes up with very large objects or very small objects together in a scene. It also can come up with objects very far from the origin (greater then a kilometer or so). This can not only effect objects but textures and IK as well.

Captain Obvious
06-06-2005, 11:27 AM
Actually, they all have this issue as it's a built-in side effect of fp math and the 32bit operating systems we are so hot to throw out. ;)

64bit boxes should help this; at least to the next limit.
All even semi-modern computers can do 64-bit fp math. ;)