[Plugin] Voronoi - Convex Hull

a4chitect

see attached jpg for instructions

thanks:
to the creators of the Qhull program (calculates voronoi, convex hull,...) http://www.qhull.org/
to this community and all people involved in sketchup/ruby/forums
licence: your only duty is to share any improvements and/or upgrades of this code under this same condition

notes:

All file locations are inside your Sketchup\Plugins\Qhull directory
All plugins can be found in sketchup under toolbar menu Plugins\Qhull

Points were created with the qhull\pointify plugin
-it converts all vertices of the selection into construction points

to construct Voronoi (or convex Hull) select the points (you don't have to worry about
different geometry in the selection set, the plugin filters out points only)
-all points are selected, you have to write them to a file for the qhull engine to process them
this can be done by pressing qhull\export cpoints

once exported, you can start the Voronoi buildup by running
qhull\voronoi
-please note that this always takes your your most recently exported cpoints
-nothing has to be selected for the construction to start

debugging:
-one error can occur while exporting points, to check this process just delete points.txt file in the qhull directory and run the qhull\export cpoints plugin
then open the newly created points.txt file and if it is not blank, all went ok
-second possible problem is that the qhull engine is unable to process your geometry (out of mathematical reasons) just check if a results file gets generated in the
qhull directory: qvoronoi.txt (of course delete any previous qvoronoi.txt before)
-the third possibility is that the constructing script cannot process the results into geometry, this is the place to let me know

when you keep getting a previous result instead of the current one, try to delete the qhull\qvoronoi.txt file manually

PLUGIN SPECIFIC
Voronoi: -sometimes result is easier for qhull to compute when you export the bounding box along with the cpoints
-i couldn't get the engine to export lines reaching infinity, so you will not get these right now
Convex hull: -when you don't want to get a simple 'box', don't export the bounding box along with cpoints

windows only
but is very easily portable for a mac - feel free to do so, you can find the mac version of qhull here: http://qhull.darwinports.com/

extract to your Sketchup\Plugins directory (folder)

tolieolson

Hi. I love the concept of the plugin. Problem is that it won't work even after I've tried deleting the old point file and creating a new one.

The details of what I'm doing:
I create a box.
Draw lines connecting sides in a random fashion, about 9 lines.
Pointify.
Export cpoints.
Click on voronoi, and all that happens is a flash of a dialog box in the corner of my screen that looks like DOS. No shape emerges.

Perhaps there is a bug that I ran into. Any tips?

AcesHigh

I must be sincere about my dumbness. I dont understand what exactly this plugin does and what uses could it have.

Any example of what type of modelling is made easier by the plugin?

kwistenbiebel

I have the same issue as AcesHigh.

It seems to be a very useful thing for a lot of people but I never understood what it does and how to get the preliminary geometry (curved 3Dlines ?) in place before using the plugin.

The lingo used (Voronoi?) sounds like chinese to me.

pav_3j

ditto

pav

remus

Well i'll add my bit here. My understanding of vornoir (or convex hull) is that its the sort of shape youd get if you draped a cloth over a shape. Apparently its useful for physics simulations, i tihnk sketchyphysics uses them for some shapes.

Im sure if you do a google search on it youll get lots of info.

a4chitect

I can't help further at the moment, but please check the link mentioned in the first post (directing to the original thread) for pictures and explanations

voronoi is a system of subdividing space - in a special way, so that each element gets enclosed in a cell while each wall is equally far from both points

convex hull is like remus said a little like wrapping your points in a stiff cloth (because it covers all concave inserts) hence the name: convex hull

script is not a normal ruby script because the whole calculation is done outside of sketchup (the already mentioned dos command prompt) in a program called qhull. I managed to tweak the script to run almost always at my pc, it is far from clean and reliable. I have posted all the possible steps to make it run, and can only wish you luck at the moment.

a4chitect

this is a little modified version, it has probably the same bugs and unreliable performance, but maybe it will work for you

replace your current 'voronoi.rb' make a bckp if possible

halroach

@tolieolson said:

Hi. I love the concept of the plugin. Problem is that it won't work even after I've tried deleting the old point file and creating a new one.

The details of what I'm doing:
I create a box.
Draw lines connecting sides in a random fashion, about 9 lines.
Pointify.
Export cpoints.
Click on voronoi, and all that happens is a flash of a dialog box in the corner of my screen that looks like DOS. No shape emerges.

Perhaps there is a bug that I ran into. Any tips?

Hi, I'm running into the same problem. Have you found a solution?

halroach

I'm getting the same problem as tolieolson's

"I create a box.
Draw lines connecting sides in a random fashion, about 9 lines.
Pointify.
Export cpoints.
Click on voronoi, and all that happens is a flash of a dialog box in the corner of my screen that looks like DOS. No shape emerges."

In the Ruby Console I get the folloing error:

Error; #<Errno;;ENOENT; No such file or directory - C;/Program Files/Google/Google SketchUp 6/Plugins\qhull\qvoronoi.txt>
C;/Program Files/Google/Google SketchUp 6/Plugins/voronoi.rb;14;in `initialize'
C;/Program Files/Google/Google SketchUp 6/Plugins/voronoi.rb;14;in `new'
C;/Program Files/Google/Google SketchUp 6/Plugins/voronoi.rb;14;in `mesh'
C;/Program Files/Google/Google SketchUp 6/Plugins/tooling/voronoi.rb;138
C;/Program Files/Google/Google SketchUp 6/Plugins/tooling/voronoi.rb;138;in `call'

suggestions?
Thanks!

sawamura

I have the same problem of Halroach.

this plugin works on sketchup 6?

i can make the points.txt file by using the extract Cpoints tool, but when i click in voronoi, nothing happends.

zhuangsuph

this is a little modified version, it has probably the same bugs and unreliable performance, but maybe it will work for you

Z_stern

I have exactly same problem with this plugin. Points are exported correctly, but "voronoi" command brings no result (and I see same errors in ruby console as user harloch had).
Sketchup Pro 6.4.112, Win XP HE.

cyin6

I have some problems with export_points.rb
Error: #<NoMethodError: undefined method `triangulate' for Qexport:Class>
where is the triangulate def called on line 89?

mcdermottadrian

Hi,

I'm having the same issues with this plugin; can generate a points file, but neither the convex hull nor voronoi does anything (just a flash of the command prompt window).

Amazing potential... if it worked. Has anyone figured this one out?

Color_Man

There are a large number of significant errors in the command structures in these scripts. the cpoints script hangs most of the time and never gets past writing the first line, unless you respond YES to adding the bounding box.

andrew1184

Anyone figured out what the deal is with these scripts? I've been trying to figure out how to write a voronoi script for Sketchup for quite a while now and every time I start looking for information the only information I find is this thread with a link to a script that doesn't work at all.

craigbic

I can get Convex Hull to work using this procedure:

Create points based on whatever geometry using Plugins>Qhull>Pointify
Export points (to points.txt file) using Plugins>Qhull>Export CPoints
Use a Windows Command Prompt to run the command "qhull.exe TI points.txt o TO qhull.txt" inside the Plugins\Qhull directory which generates the required qhull.txt file.
Back in SU, run Plugins>Qhull>Convex Hull, which does generate the convex hull - at least for me at work using SU6

However, even when I create the required qvoronoi.txt file from exported points (have tried with and without bounding box included) via the command prompt command "qhull.exe TI points.txt v Qbb o TO qvoronoi.txt" and I go back into SU and run Plugins>Qhull>Voronoi - nothing happens except a quick flash of the command prompt window. This is really frustrating since I really have a need to create voronoi-based architecture for a project and i don't want to have to go to Rhino.

Has ANYONE had any luck with this at all?

harnstein

following craig's footprints i came to the same result. no a very usable way to create qhull, but works.

how did you get to the information, that you can write "qhull.exe TI points.txt v Qbb o TO qvoronoi.txt" ?

this is real research...like going around in the woods eating everything just to find something tasty...

craigbic

@harnstein said:

how did you get to the information, that you can write "qhull.exe TI points.txt v Qbb o TO qvoronoi.txt" ?

I got that from the qhull.exe documentation from qhull.org. If you open up a command window to the qhull directory in the plugins folder of SU and type "qhull" it will bring up a list of all the little options you can add such as "Qbb" etc... Qhull is working and that's nice but what I really wanted was voronoi to work. I really hope someone takes up the mantle and get this working. I tried for hours, modifying the script and couldn't get it to function (not that I know much about Ruby mind you).

Perhaps what we'll need to do is to export the c-points and then run voronoi.exe to qvoronoi.txt and then run THATfile through MatLab or Mathematica to spit out a model.