What is the easiest way to calculate a 2v goedome node coordinates

[Gavin Armstrong]

Hello,

I am looking for a easy way of generating coordinates for a 2 frequency geodome. I would to use the coordinates to import into a cad package.

So far I have tried Pydome (Linux/python) and Rick Bones Dome software. Pydome will output data but I can get a good dome out of it the dome looks scewed and "Dome" will not run on my machine and im not sure it does coordinate anyhow. Any suggestions welcomed.

Many thanks
Gav

[TaffGoch]

Gav,

There are several geodesic software links, all on one page, at Domerama:

 http://www.domerama.com/software/geodesic-software/

Give a try, and come back, if you need further assistance.

-Taff

[Adrian Rossiter]

Hi Gav

On Sat, 15 Mar 2014, Gavin Armstrong wrote:
> I am looking for a easy way of generating coordinates for a 2 frequency
> geodome. I would to use the coordinates to import into a cad package.
>
> So far I have tried Pydome (Linux/python) and Rick Bones Dome software.
> Pydome will output data but I can get a good dome out of it the dome looks
> scewed

I just tried Pydome, and made an F2 sphere. The VRML model looked
fine. The coordinates are obvious in the .wrl file, and can be
copied if you open the file in a text editor.

> and "Dome" will not run on my machine and im not sure it does
> coordinate anyhow.

I updated Dome to build on modern systems that have a unix-like
build environment available. If you are running a linux based OS
this package should hopefully build on it (install the package you
need to build programs first). The easiest way to get coordinates
is from the OFF output, which I added as an extra format, which has
the coordinate list from line 3

http://www.antiprism.com/other/dome/


Another Python solution is an old geodesic program I wrote, which
just outputs coordinates (download link at bottom of second page)

http://packinon.sourceforge.net/py_progs/pg_geo.html
http://packinon.sourceforge.net/download/index.html#other


You could also use Antiprism, which hopefully builds on your system

http://www.antiprism.com/examples/150_named_models/570_geodesic
http://www.antiprism.com/examples/200_programs/650_geodesic/imagelist.html

Adrian.
--
Adrian Rossiter
adr...@antiprism.com
http://antiprism.com/adrian

[Gavin Armstrong]

Thanks guys,

Adrian I have anti prism working on windows, so far I can see a 3d model of the sphere on screen. I will have a play to see if I can adjust the radius and output some coordinates.

Cheers
Gavin

[Adrian Rossiter]

Hi Gav

On Sun, 16 Mar 2014, Gavin Armstrong wrote:
> Adrian I have anti prism working on windows, so far I can see a 3d model
> of the sphere on screen. I will have a play to see if I can adjust the
> radius and output some coordinates.

Just to get you started. The geodesic sphere models have radius 1.
Say you wanted radius 2 and coordinate output then the command is

off_trans -S 2 geo_2 | off2crds > coords.txt

[Gavin Armstrong]

Thanks Adrian,

 

I started with the "geodesic" command and wondered what "std_ico" and "ico" do?

 

I managed to get the coordinates into my cad program and everything looks pretty good so far.

 

Do geodesic coordinates scale, so if I have coords for a 1mm diameter geosphere can I multiply them by 1000 to get the cords for a 1M dome? 

 

Thanks again

Gavin

[Adrian Rossiter]

Hi Gavin

On Sun, 16 Mar 2014, Gavin Armstrong wrote:
> I started with the "geodesic" command and wondered what "std_ico" and "ico"
> do?

The geodesic program only processes models. To make a typical
geodesic icosahedron you would pass an icosahedron model to the
program for it to process.

Models are typically held in files, and the Antiprism programs
are passed the file name as an argument. However, Antiprism
includes a lot of models that are automatically created as
requested, and the names of these models can be used anywhere
that a model file name would be given.

For the models you asked about, "ico" is a coloured unit edged
icosahedron. However, many models have a second form that is made
by prefixing the name with "std_", which gives an uncoloured
model, with usual or nice coordinates, if these exist. The
"std_ico" model is an uncoloured icosahedron, and has coordinates
whose values are 0, +/-1 and +/-phi.

There is help for all the model names under this help section

off_util -H models

> Do geodesic coordinates scale, so if I have coords for a 1mm
> diameter geosphere can I multiply them by 1000 to get the cords for a 1M
> dome?

Yes, scaling is fine.