Maya what are default scale settings for mash ncloth xgen bifrost dynamics, and what scale do modellers ,animators,use?


#1

hi cgers
maya what are default scale settings for mash ncloth xgen bifrost dynamic systems etc new and old

i wish to model objects and landscapes and animate them, and run dynamics
and use the big vfx house settings so …

what is the best scale to use in maya preferences
ie is it 1 unit is 1cm, or 1 unit is 1m

tried 1 unit is 1m , mash wouldnt work, had to scale scatter surface to scale 0.01

or set prefs 1 unit is 1cm mash works ok.

are mash dynamics, same scale as maya dynamics and ncloth solve?

ie if you add an ncloth and ncloth solve to a mash repronode result

at a 1 unit is 1cm, ncloth solve gravity has to be 980 not default 9.8.

mayas dynamics system only in part works as different dynamics systems wont interact and have different scales,
i cannot get ncloth to work on a per scattered object case in mash


so what is mash assumed scale?
so what is mash dynamics assumed scale?
so what is ncloth assumed scale?
so what is ncloth dynamics assumed scale?
so what is xgen assumed scale?
so what is xgen dynamics assumed scale?
so what is bifrost assumed scale?
so what is bifrost dynamics assumed scale?
so what is old bifrost assumed scale?
so what is old bifrost dynamics assumed scale?
so what is paintfx assumed scale?
so what is paintfx dynamics assumed scale?
so what is nhair assumed scale?
so what is nhair dynamics assumed scale?
so what is hardmesh assumed scale says scene size 100cm
so what is arnold assumed scale say for sss and transparency ?
do different solvers ie mash and ncloth have different scales
is gravity the same, if not why not gravity is always the same

feel free to add to this list to help others

is it the case for some of these same list below
regardless of what settings maya units has in preferencers,
the scale is ignored and 1 unit will always be cm or m regardless of what you
set for ? ( aka dumb setting): which of these is it

so what is mash assumed scale?
so what is mash dynamics assumed scale?
so what is ncloth assumed scale?
so what is ncloth dynamics assumed scale?
so what is xgen assumed scale?
so what is xgen dynamics assumed scale?
so what is bifrost assumed scale?
so what is bifrost dynamics assumed scale?
so what is old bifrost assumed scale?
so what is old bifrost dynamics assumed scale?
so what is paintfx assumed scale?
so what is paintfx dynamics assumed scale?
so what is nhair assumed scale?
so what is nhair dynamics assumed scale?
so what is hardmesh assumed scale says scene size 100cm
so what is arnold assumed scale say for sss and transparency ?
do different solvers ie mash and ncloth have different scales
is gravity the same, if not why not gravity is always the same

feel free to add to this list to help others

and who started this mess
the point being a 3d operator needs all these
systems to work together,
and suggest a…desk get developers and themselves to
decide on a common scale and framework for node interusability

what scale does hollywwod vfx, use
ie weta, ilm,method,framestore, mpc, rsp, pixomondo, rodeo.

in maya for these companies 1 unit is what 1cm or 1m?
and in their dynamics 1 unit is it fixed at or scalable?
what is their gravity?


#2

just enter the bifrost world and all will be good. :grinning:


#3

so far i have not sure if correct: only looking at stuff on sites?

bifrost or boss default
1 unit is 1m always
gravity def9.8?

if
in prefs
1 unit is 1cm

have to scale scene down to 0.01

where to set bifrost scale besides model scene scale at 0.01?
or can i just set master voxel size, or do all temperature settings vary with model size?
what is gravity setting 980?
“For example, if your scene is modeled to a scale of 1 unit being equal to 1 centimeter, then you should change the value of Gravity Magnitude on the bifrostLiquidContainer node to 980 (9.8m/s2 = 980cm/s2). This may cause some issues related to high velocity values relative to the voxel size, in which case you may need adjust the transport step values”


ncloth default
1 unit is 1m always
gravity def9.8?
maybe

if
in prefs
if 1 unit is 1cm

set ncloth space scale to 0.01?

BUT do not have to scale the scene down? this is different from bifrost and boss?
and set gravity 980


mash default
1unit is 1cm? not sure
gravity def9.8?

if
1 unit is 1m …run into problems straightaway
on a scatter object , instances wrong scale.

have to scale scene down 0.01
and gravity always 9.8?


maya arnold
def scale
1 unit is 1cm not sure?

if in prefs
1 unit is 1m
sss scale is 0.01
transparency scale is 0.01 not sure?


hardmesh cannot change
needs model size 100cm

bad?


do big vx house modellers,riggers,animators
use
maya def 1 unit is 1cm

or do they
match dynamics and use
in prefs
1 unit is 1m


so my question is what scale
do big fx houses
build their models, buildings, characters, landscapes, to
and more importantly animations of characters probably harder to change scale.
ditto for sending maya assets between vfx houses do they use same scale.
maya arnold , vray render scale is it the same as above

do they set in prefs
def maya
1 unit is 1 cm, and set dynamics to this

or do they set in prefs
1 unit is 1m and set dynamics this.

i wouldnt think they constantly scale scenes to run dynamic simulations

( there was a similar thread but trying to do what vfx houses actually do regards scale
https://forums.cgsociety.org/t/working-in-1cm-1cm-scale-in-bifrost/1798648

1 would rather get a vfx pipeline supervisor type opinion , as against modeller, or dynamics artist otherwise
you will end up whats good for them is not the actual pipeline scale that suits all needs?


#4

We work in cm.
We are scaleing dummy scenes to the right scale for simulation.
We bake everything into alembic or vdb.


#5

If you are in new Bifrost follow this vid.


#6

hi oglu,

video left out important info

in prefs was for this maya scene
maya def 1 unit is 1 cm or
was
maya 1 unit was 1m not known (other videos in series suggest prefs was 1 unit is 1m)

not sure in explained overlay said grid was 1m, when in fact maybe 1cm in viewport.

gravity 9.8 or 980 not mentioned at all


presumably

group scale was for spaceship alone, assuming no element of bifrost scaled.


the fact that 3d operator sets a bifrost scale
that still doesnt adjust other nodes automatically
is plain stupid,
i wouldnt have known which nodes to scale except for this video.
(aimed at a…desk only)


seperate to this video, oglu,
so you are scaling dummy scenes more to save ram?
and presumably scaling all character animation as well

so in your case
if
you are using
maya def 1 unit is 1 cm,
and scaling all maya scene and anim to 0.01,

what is the correct scale , surely aero solve scale cannot be 1 unit is 1m,
as in video he didnt scale his geo by 0.01.


and what about boss scale,
scaling animated rigs

and ncloth ,xgen,and mash interaction

is it better just to do eveything
modelling,animating,dynamics at prefs 1 unit is 1m
what are drawbacks besides mash error(solvable with transform mash node maybe).


confusion reigns


#7

There are no fixed rules. Thats why you have TDs to make it work. They change per show or project. What does work in one scene might not work in an other.

Gravity is no fixed parameter. We use a gravity of 5 if that does look better. We cheat whats needed. We scale whats needed.

The only rule is make it look right.


#8

How we would do a water splah.
We model and animate the creature and terrain in cm.

We export a lowres version to alembic.
Scale everything down to work in meter.
Do the old bifrost fluid water sim.
Export the meshed water to alembic.
Import the water into the original scene and scale it up.

We do not change the maya units.