I’ve seen some threads that were close but to this topic but doesn’t quite answer my question because I an trying to find an object’s absolute world position after moving that object using a link constraint.
Say I have $box001.pos = [0,0,0]
I put a link constraint on it and link it to, say, $sphere001, and move $sphere001 to [100,-100,0].
At that point I link $box001 to the World.
Later, I want to move $box001 to an absolute World position, say [25, 25, 0]
Using $box.pos = [25, 25, 0], the $box001 winds up at [125, -75, 0] because $box001.pos has been offset relative to $sphere001’s movement.
$box001’s node is actually located at [125, -75, 0] but
$box001.pos returns [25, 25, 0] (even though $box001 is truly [125, -75, 0])
in coordsys world $box001.pos returns [25, 25, 0]
$box001.center is close but returns [125, -75, <num> (depending on the height)] and I don’t want have to keep offsetting for the height of my $box001.
$box.transform.position returns [125, -75, 0] but I can’t seem to be able to actually move the object using that control.
$box001.node returns an error.
Apologies if this is a simple question but there something like .pos that returns the absolute world value that is not affected by linked movements?
an objects .pos & .rotation are usually derived form the animation controller, and are never absolute.
an objects .transform value is always absolute.
try:
$box001.transform.pos
Edit: oh I see you are trying to write a value not read it.
You can set obj.transform but not individual transform components like obj.transform.pos
There is probably a way to do this by ripping apart the Pos, rotate and scale components of and rebuilding a new transform value, as Bobo explains in his CG Academy Video Series
But I would simply spawn a point helper where I want the box to go and then set $Box001.transform=$point01.transform
Of course, make a point at the target location and align my object to it.
:banghead:
I’m kind of secretly glad that the way to accomplish what I asked for is
by ripping apart the Pos, rotate and scale components of and rebuilding a new transform value
Makes me feel like it was a reasonable request to be posted on a forum. Thanks for the links!
values of #pos, #rotation, and #scale are in parent coordinate system
there is a way how to set transsform position part, and apply transform to a node:
tm = node.transform
tm[4] = pos -- absolute (world) position
node.transform = tm
tm = node.transform
tm[4] = pos -- absolute (world) position
node.transform = tm
So, if I understand this correctly…
You make an array “tm”, populated with the node.transform information.
Then you change tm[4] (the position information)
Then you assign all of the array’s information back to node.transform
Is that what I’m seeing here?
Dennis’ solution is great.
You are basically correct. However, obj.transform returns a Matrix 3value, not an array value.
the you tube videos I linked to above are a very good explanation of Max’s matrixes.
here is what it means:
tm = node.tramsform
makes a copy of a specified node transform which is a Matrix3 value
tm[4] = pos
sets row4 (which is position part of matrix3) using a specified position
node.transform = tm
sets specified matrix3 value as world transform of a specified node
b = box()
print b.pos
tm = b.transform
tm[4] = [10,0,0]
print tm
b.transform = tm
Wow! Thank you!
This is exactly what I was looking for.
Thank you both!
:bowdown: