Hi,

I just checked out your transfer code and saved it as a file. Thanks.

Questions:

How to use these macros? Do I have to convert each shape piece by piece?

Do you have a version of code, where the name and path of that file that
is to be converted could be typed into a variable, and then your code
would open that POV-Ray scene and convert it?

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And can it convert blobs and boxes and torus, too? And other shapes?

And how would I use these macros, can you give an example?

Thanks a lot. :-)

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Hm, that's odd, the original post seems to have vanished. I can see your most
recent two replies, but not the original thread...

Sven Littkowski <jam### [at] yahoocom> wrote:
> And can it convert blobs and boxes and torus, too? And other shapes?
>
> And how would I use these macros, can you give an example?
>
> Thanks a lot. :-)

The two macros in that post simply create a sphere and a cylinder in the
OpenSCAD language. That's all I have, because that's all I needed for what I was
making at the time. I think I included a couple of example calls at the end of
the post. I never wrote anything for converting pre-existing POV-Ray SDL,
because the data I was converting was already in the form of POV-Ray point
arrays.

In principle, it should be possible to extend this idea to convert certain
POV-Ray primitives by parsing the SDL - according to the documentation, OpenSCAD
supports spheres, boxes, cylinders, cones, arbitrary polyhedra, and extruded
shapes like disks and prisms. But I would think it would be easier to do this in
an external language with better string parsing abilities to be honest, and it
could be quite a lengthy task...

Bill

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Yes, it is a task. But here we have already the begin of something, that
could be very useful for every POV-Ray user who wants to 3D print
his/her scenes. I hope, some software developers among us will pick up
this task. Maybe even the next version of POV-Ray has a built-in
converter, based on OpenSCAD conversion and shape tesselation...

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On 26/01/2016 10:03, Sven Littkowski wrote:
> Yes, it is a task. But here we have already the begin of something, that
> could be very useful for every POV-Ray user who wants to 3D print
> his/her scenes. I hope, some software developers among us will pick up
> this task. Maybe even the next version of POV-Ray has a built-in
> converter, based on OpenSCAD conversion and shape tesselation...
> 

It is something I have actively considered.

I have a 3D printer and was pretty unhappy with the available freeware
parametric tools for creating models.

I also think POV-Ray has a leg up in this area, too, for the future
time when full-color 3D printing becomes more common: since we model
solids, our native textures go right through the object and scale
properly with it, and will appear in the right places no matter how
it's sliced or diced.

While STL doesn't currently support color information I can see a time
when this starts to matter more.

-- Chris

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Yes, I too have a 3D printer, I just purchased it and am still on my
(long) way to assemble it. There are already some layer-printing 3D
printers, that can use two or up to four different colors of the raw
filament. And there are also those 3D printers, that have full support
of colors if it comes to the print-out item. And there are those new
liquid 3D printers, they allow still only one color.

I think, a new version of STL would address the different colors. Maybe
by requesting a feed from the 2nd or 3rd or 4th filament spool (if it is
a layer-printer). Or even mixing colors fully, like with these
true-color 3D printers. At print begin, the STL language simply has to
check, what type of printer it is, and then make decisions what colors
to define, and in which way.

If POV-Ray could export to STL or at least to OpenSCAD, it would open
entire new worlds! And yes, it's time.

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Le 26/01/2016 00:13, Chris Cason a écrit :
> While STL doesn't currently support color information I can see a time
> when this starts to matter more.

The problem is not that there is no color in STL, it is that the *smart* 
*** have forked the specification for the colours in two variants, 
without being able to identify in the file which format was use. (at 
least for binary STL). And they are not compatible at all.

Figure: both format have 16 bits, in "atttribute byte count", one format 
uses it as B5G5R5V+, and the other formats uses it as R5G5B5V-
(V for validity, in contrast to a default colour or anything else)

Blue-Green-Red vs Red-Green-Blue. It's even worst than little vs big 
endian. (Yellow can be badly printed as Cyan and so on)

And as stated in the english wikipedia for stl file format, there is no 
transparency... 15 bits colours is probably too much, that's 32768 colours.

Notice that Shapeways have colour for the sandstone material. I do not 
know which of the two formats they use. But at least for sandstone, 
there is no hope of transparency.

and to finish it: rgb color system... without any gamma specification... 
for printer that are more likely to use cmyk. Pure colours are fine (at 
least the 8 of the cube: red, blue, black...), but beware of 
intermediate ones, your print might not be identical to the preview.

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"Bill Pragnell" <bil### [at] hotmailcom> wrote:
> Hm, that's odd, the original post seems to have vanished. I can see your most
> recent two replies, but not the original thread...

Is this the original post?

http://news.povray.org/povray.general/thread/%3Cweb.567c12ae9ac2ad15295a0fac0%40news.povray.org%3E/?mtop=403769&moff=10

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"Kenneth" <kdw### [at] gmailcom> wrote:
> "Bill Pragnell" <bil### [at] hotmailcom> wrote:
> > Hm, that's odd, the original post seems to have vanished. I can see your most
> > recent two replies, but not the original thread...
>
> Is this the original post?
>
>
http://news.povray.org/povray.general/thread/%3Cweb.567c12ae9ac2ad15295a0fac0%40news.povray.org%3E/?mtop=403769&moff=
10

Well that thread contains the answer I was talking about. I meant that Sven
asked the question again, and I replied, but then both posts disappeared.
Subsequent replies showed up as this thread.

I'm using the web view mostly, this might not have happened on a news client.

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