twisted motion path banked rollercoaster

cunnax · 2014-12-21 23:23:33 UTC

In maya how do you do a curve profile with banking like a hot wheels track
please see attached:
https://www.flickr.com/photos/93465359@N03/15890364940/

1: nurbs extrude profile using a curve, profile snapped to end of path curve no proper banking,
path was based on poly helix extract curve from edge

2: nurbs extrude same profile distance option ,attach to motion path, motion path ffd
3: was a drawn ep path extude same profile along curve

Out of the box maya has Twisted motion paths seen clearly with mayas flow path object

maya offers you every solution, accept an actual solution get rid of the twist in the
first place, other programs don’t flip objects going down a motion path.

it is very hard to move the ffd points as no local rotation and the whole curve from twist
onwards is affected

solutions suggested on the web don’t seem to work

4: offset path motion path world up look at locator on offset motion path… failed

5: offset curve, surface lofted between curves, used poly edge to curve as path… failed

1 was wondering is there an accepted approach for a hot wheels type track

zaskar · 2014-12-23 03:45:02 UTC

I think you should take full control about which direction the track faces if you use an additional curve which serves as a “banking target”. This not only avoids the unpredictable twisting but allows you to freely shape the road track. You can use a camera with aim and up for constraining both to direction and banking. Then simply parent the profile curve below the camera transform an then animate the profile curves rotate value to adjust the banking. After all, create an animated sweep.

The setup could look like the following:

create rail curve and bank target curve
create a camera with aim and up
attach a locator via motion path to the rail curve, parent the camera under that locator
attach a second locator via second motion path to the rail curve, set the motion path start and end time to 1 less as the first motion path, parent the cameraAim below that second locator
create a closest point on curve node, connect the bank target curve as input curve, set the first locator as query point for the closest point on curve node, then set the closestPointOnCurve node position output as translate input for the cameraUp
parent the profile curve under the camera transform, then create an animated sweep out of the curve

cunnax · 2014-12-23 16:15:33 UTC

hi zaskar
thanks for the reply
looks promising

1 was following your notes
but you lost me at step 5
i selected the bank target curve as input curve when pressing closet point constraint node

2 nodes created as a result: cpconstraintin and cpconstraintpos

but unsure how you actually linked these as a query point and translate input where are these connections made, did you move these nodes from default positions

are these connections made in the relationship editor or channel attribute box or elsewhere.

any help much appreciated

thanks

zaskar · 2014-12-24 10:45:41 UTC

If you are using “Constrain->Closest Point” just select the bank curve and hit create. Then parent the locator “cpConstraintIn” under the same locator as the camera. Finally parent the cameraUp under the locator “cpConstraintPos”.
If you want to create all from scratch type “createNode nearestPointOnCurve” into the MEL executer, then open the ConnectionEditor and make following connections:
bankCurveShape.worldSpace > nearestPointOnCurve.inputCurve
locator1.translate > nearestPointOnCurve.inPosition
nearestPointOnCurve.position > cameraUp.translate

cunnax · 2014-12-26 22:18:31 UTC

hi Zaskar

thanks for that very informative,

I presume you are snapping the camera aim to locator two,
and camera up to the beginning of the bank offset curve
and rotating the camera group so its up looks at the bank curve,
before
making the connection editor connections,

I am still not sure why maya decides to do a complete 360 while pushing geo down a motion path something fundamentally must be wrong with the
way maya draws curves

cunnax · 2014-12-27 23:39:09 UTC

As a twist on zaskars method to get closer to a 3dsmax path deform modifier
I did the following, I have varied from zaskars method just using object up using a locator on an offset track

please see attachedhttps://www.flickr.com/photos/93465359@N03/16125301002/

1 :an offset curve with some cvs moved with locator
attached with motion path, rail curve and profile curve
object up using locator, banked track animation sweep ok.

2:a_as per 1: an offset curve with some cvs moved with locator
attached with motion path,
2:b_extruded geo attached to motion path object up using locator,
extruded geo flips along path

3:a_as per 1: an offset curve with some cvs moved with locator
attached with motion path,
3:b_extruded geo attached to motion path object up using locator,
extruded geo flips along path

4:a_as per 1: an offset curve with some cvs moved with locator
attached with motion path,
4:b_extruded geo attached to motion path object up using locator,
extruded geo flips along path

this system cannot use animated sweep as actual geo not a profile curve.
bad twist still occurs

cunnax · 2014-12-28 14:20:46 UTC

MAYA PROBLEM IS THE FLOW PATH OBJECT DOES NOT TAKE VECTOR UP INFORMATION FROM THE ANIMATED PROFILE MOTION PATH
please see attached :
https://www.flickr.com/photos/93465359@N03/15512386463/

1: profile curve
2: offset curve
3: rail curve
4: locater offset look at
5:extruded_geo parented
to profile curve
6:animated sweep using profile on motion path ok
7:flow path object of same profile on motion path has twist
8:flow path object of same profile on motion path has twist
extruded geo parented to profile twists flips 180 degrees

cunnax · 2014-12-28 21:13:40 UTC

please see attachedhttps://www.flickr.com/photos/93465359@N03/15515122223/

1: before camera up position here say as camera doesnt jump to nearest point oncurve after connecting translate
2: after camera up position here say as camera doesnt jump to nearest point on curve but some other point after connecting translate
not sure if zaskars camera has to be at 000 or on the curve or where the aim and up are before parenting and before connecting or wether any frozen transforms.

ONLY THING I AM SURE OF IS MAYAS MOTION PATHS AND FLOW OBJECT ARE IN A TOTAL MESS,

the idea of using this system if you had say 50 parametric pipes on a building is a worry.

cunnax · 2014-12-29 19:17:39 UTC

pushing geo down a motion path in maya

please see attachedhttps://www.flickr.com/photos/93465359@N03/15956167120/

1: start with any setting that has no flow path lattice twists here vector 0 0 z 1

2: rotate lattice cross sections to your required bank

i would like to know an easier solution as rotating every lattice cross section is slow

only done limited testing , all I know is any twist even one is big problems to get rid of
95% of mayas motion flow path offerings have built in twist.

cunnax · 2014-12-29 23:29:20 UTC

UNSTABLE FLOW PATH WHEN ANIMATION RUNNING
please see attachedhttps://www.flickr.com/photos/93465359@N03/15957385438/

1: motion path object up using locator1 on offset motion path some cvs moved
geo attached to motion path object up using locator 1, flow path as some lattice twist
removed

2: when animated the flow path lattice rotates by itself causing the geo to unwanted
rotate round central motion path see *,

I have found the main cause of flow path lattice twist to be when the main path runs directly
above itself.

cunnax · 2015-01-02 12:03:43 UTC

a link to zaskars

lattice script on another thread:

http://forums.cgsociety.org/showthread.php?p=7963152#post7963152

cunnax · 2020-08-20 01:53:38 UTC

wanted to add this as a possible solution.
maya offset curve, loft surface, extrude faces insert loops extrude faces
or use 3dsmax blender cinema4d out of box and both have history

not really a solution to the animated rollercoaster cars more the track itself

sofar blender best 15 min solution for me 5 mins toutube tut 10 mins blender send fbx to maya

please see
https://www.flickr.com/photos/93465359@N03/50253406751
getting quicker to do it in blender from scratch to final output.
Build & Animate A Roller Coaster and this was 2016
https://www.youtube.com/watch?v=Iob2BzxEVLY
and you get access to your files anytime in the future, not pay for access
anywhere you want not on cloud,
whatever operating system you want, whatever gpu you want

that tutorial solves all the problems i have with maya animated rollercoasters
, its not maya and its free
go figure, i am being stupid? learnt it all in 15mins flat…

maya motion paths best settings IS THIS CORRECT NOT SURE?
see attached
https://www.flickr.com/photos/93465359@N03/50257199927

motion path and flow path if bezier curve
only vector def vectorx0y1z0 is twisted x0y0z1 is untwisted…normal is twisted

motion path and flow path if bezier curve converted to nurbs
only vector def vectorx0y1z0 is twisted x0y0z1 is untwisted…normal is twisted

xx this is best xx
motion path and flow path if bezier curve converted to nurbs rebuilt as ep1 with say 50divs
only vector def vectorx0y1z0 is twisted x0y0z1 is untwisted…normal is untwisted

i dont have a clue what normal the endpoints are on a bezier or cv curve as compared ep1 cv
i doubt wether maya does either?

quickest check create an object longtrain ,
attach to a looped curve motion path create the flow pathh ffd with lots of division
so you can see the twists in the curve on all options,
the end points are wierd?

the question really is why is maya not fast at the basics?