[Closed] How to find inner contour of an object?

Did you try shape booleans introduced in newer max versions?
If shape boolean isn’t an option you could start with something like this

delete objects
delete helpers
gc()
Rectangle length:1300 width:100 cornerRadius:0 pos:[-750,-50,0] wirecolor:white
Rectangle length:100 width:1700 cornerRadius:0 pos:[150,550,0] wirecolor:white
Rectangle length:1600 width:100 cornerRadius:0 pos:[950,-300,0] wirecolor:white
Rectangle length:100 width:1200 cornerRadius:0 pos:[-100,-650,0] wirecolor:white
Rectangle length:800 width:200 cornerRadius:0 pos:[400,-200,0] wirecolor:white
Rectangle length:100 width:700 cornerRadius:0 pos:[-50,150,0] wirecolor:white
Rectangle length:500 width:100 cornerRadius:0 pos:[-150,-150,0] wirecolor:white
Rectangle length:100 width:300 cornerRadius:0 pos:[650,-250,0] wirecolor:white
Rectangle length:100 width:1200 cornerRadius:0 pos:[300,-950,0] wirecolor:white
Rectangle length:600 width:200 cornerRadius:0 pos:[-700,-1000,0] wirecolor:white
Rectangle length:100 width:1800 cornerRadius:0 pos:[300,-1250,0] wirecolor:white
Rectangle length:1000 width:100 cornerRadius:0 pos:[1150,-700,0] wirecolor:white
Rectangle length:100 width:600 cornerRadius:0 pos:[1300,-150,0] wirecolor:white

redrawViews()
sleep 1.0
bounds = shapes.max - shapes.min
tri = plane widthsegments:1 lengthsegments:1 width:bounds.x length:bounds.y pos:shapes.center wirecolor:yellow
convertToMesh tri

redrawViews()
sleep 1.0

for s in shapes do
(
	x = copy s pos:(s.pos - z_axis)	
	addModifier x (Extrude amount:10)
	tri -= x -- mesh boolean
	delete x
	redrawViews()
	sleep 0.15
)

update tri
select tri

Gif

ePiiECLZ7R.gif727×554 345 KB

Thank you.
With simple objects works with no problems. With complex objects 3dsMax is crashing.

I’ve tried with shapeBoolean, I think there is a post from you somewhere on the forum, but… if the proper rectangles are not selected the result is wrong.

http://www.angusj.com/delphi/clipper.php
I use it to get the outline like the selection line , also to

I have a version which combines all rectangles -> collapse to mesh -> weled and exctract borders, but it needs the proper rectangles to be selected manually. What I am trying to do is to find a way to tell the scirpt:
“those are all the rectangles, find the inner outline”, with no success so far. My next ideas:

• create a grid of points all over the rectangles area
• remove all points inside the rectangles
• use the rest of the points, which should be placed inside the “inner” area to find the outline
  Most probably this will take too much time.

• start from a point, manually placed inside the “inner” area
• find the closest segment
• use this segment to find the next one, it may be on the same rectangle or on another rectangle
• loop until the first closest point is reached again
  Most probably this will take much time than my first idea, because here I have to calculate segments intersections, where the intersection point is located, etc.

I know about it. Did you managed to use it inside 3ds Max with mesh/spline objects?

my usage

Thank you.
If you want to share the secret, feel free to do it.

post, posted after 8 attempts.

if you want pure mxs solution look at this one as well. Not really fast even with simple cases and also splines must intersect in order it to produce correct resulting polygon
http://www.scriptspot.com/3ds-max/scripts/zoa-spline-2-poly

@AEI Do you have any idea why could it be so imprecise at low point count?

I just wrote a very rudimentary algorithm that extracts the inner shapes or outer shape without the need of converting to mesh or attaching the shapes.

It seems to work with a test model I build based on your draws, but I don’t know if it would work with any scene you may have.

inner_shapes_01.gif742×414 26 KB

What I don’t understand is what you mean when you say:

I also have to somehow tell the algorithm which are the rectangles, otherwise where is it supposed to look for?