Forum

Equally distanced point in bezier curves


#1

(apart from going b-spline) how can i get equally distanced points along the bezier curves using the VL Bezier nodes as showed in the patch? Is it even possible? I also need to set a given number of points for each curve. (for LED mapping)

Bezier_test.zip (6.3 KB)

EDIT: another way to look at it is: is it possible to have multiples not connected bezier curves?


#2

There should be some examples, you need a node called PathLength, iirc.


#3

I think you mean Arc Lenght but still how to get an arbitrary number of sampled points for each curve? That is, each led strip has a different length so that each has a different number of LEDs, or even LED resolution per meter.


#4

yes, ArcLength was the name.
since you can sample the curve with a parameter from 0-1 you only need to provide a spread with the right sample parameters, a linear spread for example.
also, the nodes are fully spreadable, so just load save multiple curves.


#5

Yes this is ok, what I don t get is how to treat each curve a individual curve and assign a sampling number to each, if I input a linear spread to Arch Lenght it will apply it along all the curves, there is a Position Bin Size input pin, but it is not behaving as I would expect. See the attached patch.


#6

you need multiple curves (spread), not multiple segments in one curve…


#7

Yes, that s the point, but the bezier editor does not allow that (?)


#8

not sure, need to ask @robotanton how to handle that. maybe just use multiple editors…


#9

Hello @io,

yes, at the moment BezierEditor can work only with one curve. Unfortunately.
So you need two or many BezierEditors, like in the example attached. You can also turn them on/off,

Best,
Anton

Bezier-MultipleCurves.zip (4.0 KB)


#10

@robotanton I have a similar issue to solve. I was thinking since all the nodes are VL nodes, why not build the whole thing in VL, where you could easily use foreach. I have any number of curves I want to sample at certain points, so using multiple editors in vvvv is not an option.

So BezierEditor can not be used in foreach it seems. Weirdly the Reader(BezierSpline) remains greyed out when connecting a path to it.

Is there any existing VL nodes that can do what B-Spline and PathVectors could do in vvvv?


#11

just to share my piece of the bezier cake:

I tried to use the vl modules about 1.5 years back to create a camera path. my intention was it to follow a series of stationary points where the camera would break into and come to a stop, stay for a while, then switch focus, and eventually continue at my will at the spline in a smooth fashion.

it failed me basically along the same lines as it did for seltzdesign and io: it did not spread well, in a way where bezier slices literally make ends meet, and stay put.

i frankensteined something together from the old vvvv and the new vl ones, however, it turned out to be a binsizing nightmare, because the vvvv nodes count the count different somehow afair.

long story short, since then I kept away from bezier camera paths. which is a shame, because it would certainly be a nice tool for storytelling23