Replace Mesh MUSH
5 messages in this thread
A true story:
Three-hundred and fifty cars zooming down a freeway, congestion, brake lights
flash, cars slow to a crawl — the animation almost to perfection…a feat of
single-minded determination!
With only 24 hours remaining till the deadline, the animator, with special
satisfaction, takes a break… One last little detail and the project goes out
on the net, and the animator can sleep a full night for the first time in
months… All that remains to be done is to use Replace Mesh to update all
those ugly box-mobiles to become Tercels in twelve contemporary colors. The
command is executed, but the result is an explosion of parts in a heap at each
end of the freeway!
Now it is 5:00 am, and I am trying to figure out what went wrong:
1) I started with twelve identical "box" cars in twelve different colors.
2) I detached one of the rear faces from each car as a "brake light".
3) I linked each light to a car in Keyframer.
4) I also created a set of high-resolution cars with the same names and links.
5) The bounding boxes and pivot points for both sets of meshes were identical
— except for the tail lights.
5) … then I animated hundreds of instances…
6) When I did my Replace Mesh, I ended up with tail lights strewn all over the
freeway…
7) The after the Replace, the brake lights were correctly placed in 3D Editor,
but in the Keyframer at frame 0, they had gotten completely mixed up on the
master objects. Some were stacked neatly in a pile, one placed correctly, and
one properly named light did not get replaced. The instances were a total
mess, with brake lights strewn hither and tither…
8) I tried patiently moving the lights back onto their parents, deleting the
instances (one at a time…), saving and re-Replacing the mesh, but the exact
same thing happened!
Questions:
A) Why would the keyframer show geometry differently in frame 0 than in the 3D
Editor. (Yes, there were linked parts, but none of their parents moved–only
the instances were animated.)
B) Why would (most of) the child (master) parts end up in a neat pile?
C) Why me?
—Donald Newlands
I need more info on this to offer you my opinion:
>> can sleep a full night for the first time in months…
How is it that you get "months" to do a project like this?
We have been going full tilt all summer to get everything else out of
the way so that we can spend two months round the clock on this one
project… (3+ minutes)
We are animating several freeways and showing their conversion to
"Automated Highways" (a cross between auto-pilot and the Denver
Airport baggage system). The sequences that we are producing involve
a few detailed freeway models, and hundreds of cars.
We have been using a early-release of the Russian "3D Power"
utilities (Digimation) to slide the tracks of the cars out in time,
but the software is still very tempramental…
Last night I dreamed that I was in 3D Studio. Rendered (yellow) car
hoods were coming down a conveyor belt, and every time that one of
them passed over me, I had to go into the Tracks Editor and change
its key… I must be losing it. The last time I had a dream like
that, I was in AutoCAD 1.? and everything was wireframe!
Don,
I have experienced the same problem and it seems to be related to the "missing
link" between the 3d editor and the keyframer. My understanding is that both
modules were developed separately and forced to work together. The result is
that occasional incomprehensible (to me, anyway) things will occur when dealing
with linked objects. I think the problem relates to the different axes of your
box cars and your final Tercels when you did the Replace Mesh.
I have had complete keyframed scenes go nuts on me too. I have learned that
once an object is keyframed, you usually cannot replace it or unlink it without
diastrous results — as you have found. I don't think there is an easy solution
to your situation. This probably won't work but I would try going back to your
original box-car file and try replacing them one at a time with modified
versions of your Tercel (to see if by altering some of the geometry or pivot
points or axes, they will be accepted into the scene.)
Another thing I would try is to go back to the 3d editor, take a Tercel apart
into elements and and try rebuilding the box-cars into Tercels by attaching
elements to them or reshaping the geometry, etc. That might be a way to fool
the keyframer into accepting them
Sounds terrible. Good luck.
Alec Jason
Thanks for the reply. It looks like we'll be rebuilding the cars'
animation again for the 999th time… I have been incredibly
methodical through the whole project.
The boxes and the Tercels actually replace each other fine, but the
linked tail lights, which were added to both scenes later, go
completely whacko.
Axes ARE really odd between 3D Editor and Keyframer: The first time I
tested the replace function, my cars all went down the road sliding
on their tails.