Mesh Distortion
8 messages in this thread
I am having a strange problem with an animation that I am doing using
release 3 of 3dstudio. The file consists of a 3d landscape and a
truck. The landscape is very large and compicated (over 200,000
vertices and 150,000 faces), it is also far away from 0,0,0. The
problem is whenever I do anything to the truck, such as rotate it or
scale it, it deforms horribly. The result is not usable. Has anyone
seen this before? What causes it and how do I prevent it without
moving my landscape?
Hi Robert,
<< The problem is whenever I do anything to the truck, such as rotate it or
scale it, it deforms horribly. >>
Can you be more specific as to what steps you performed and what the distorted
mesh looks like?
The landscape comes from autocad in a location far from 0,0,0
the truck comes from a 3ds file and is located near 0,0,0
so I move the truck so it is on the road, and it remains ok
then I must scale it to 75% its original size and then rotate it -32 degrees.
When you rotate it the models vertices do not move evenly, resulting in
a distorted version of the mesh. It looks psychedelic.
>> in a location far from 0,0,0…
Try relocating your landscape closer to the origin. (FWIW, there is another
recent thread in the forum discussing the relationship of detail size to
overall scene size.)
– Dave
What are the dimensions of the landscape and the truck?
– G
The site is four miles long, the truck is the front of a semi and is about 11'
6"
I have tried several different trucks inserted into this file, but the result
is
always the same, psychedelic. No matter which mesh I insert the vertices rotate
improperly
and the result is unuseable. Could it be a rounding error due to the distance
from 0,0,0 ?
>>PMJI>>
Robert,
A while back I had a similar problem with a camera path jumping around and
this was also a large civil job. The scale and location of your scene has
caused some single-precision floating-point roundoff errors, which will make
the vertices fall onto there closest roundoff points, therefore causing a
distorted mesh.
Your solution would be to just translate the model to its origin (0,0,0) and
all should be fine.
-Mike
As Mike said, it's very important that your scene is centered around the
origin. Is it?
– G