Dan Shriver tabbydan at gmail.com
Sun Oct 9 13:00:09 EDT 2016

```I want to make sure I understand your response.

When you say "tori" you don't mean each is a torus, but each is a slice of
a torus, right?

I'm trying to make a torus of 360 slices, the goal being that if I can do
that I can change each slice a little bit so the torus "morphs".

I have been doing this kind of thing with linear_extrude() and am just
doing a test here to make sure my approach with rotate_extrude() is correct.

You are indicating that  it will be slow and painful the way I'm doing it.
Is there any way inside of OpenSCAD for me to make it faster (like
rotate_extrude() does if it does the entire 360 itself) without decreasing
the number of slices?

On Sun, Oct 9, 2016 at 12:32 PM, nop head <nop.head at gmail.com> wrote:

> The only thing you are asking CGAL to do is union 360 overlapping tori, so
> that is what it will be trying to do. That will take a time approaching
> infinity as union is very slow especially with overlapping shapes with lots
> of vertices.
>
> On 9 October 2016 at 17:05, Dan Shriver <tabbydan at gmail.com> wrote:
>
>> I know this is is somewhat of a bad question (because CGAL is a black
>> box...) but, even if the progress bar is a complete lie (which it usually
>> is for me) is there some way that I can tell that openSCAD is still doing
>> something and hasn't stopped?
>>
>> I ask because I have some simple test code:
>>
>> module testTorus() {
>>   for (i = [0:360]) {
>>     translate([(20*cos(i)),(20*sin(i)),0]) {
>>       rotate_extrude(angle=1, convexity=10){
>>         translate([20,20,0]) {
>>           circle(r=10,\$fn=5);
>>         }
>>       }
>>     }
>>   }
>> }
>>
>> I ask it to run and I get "Rendering Polygon Mesh using CGAL..." and no
>> other indication that things are progressing and just want to be sure it is
>> still working.
>>
>> Why am I doing things this very painful way when I could just
>> rotate_extrude through 360 degrees?  This is just a simple test case to see
>> if what I am doing will work.  When I actually implement things I will have
>> the different slices each be slightly different.
>>
>> _______________________________________________
>>
>>
>
> _______________________________________________