hello!
Once again something that looked fairly simple in the start got to a huge
headache....

i hope the attachment goes through, there you can see my actual tries to
get this working....
it started by wanting to remix a nice fountain found on thingieverse, but
where the sizes were just so wrong for me that my available pump didn't fit
into it....

So I needed some slanted outer walls, and pierced inner walls, since the
theme was hexagons, I did everything in hexagons.....

I started by using cubes, but the slanting didn't go too well.... so I
started with a polygon, but the need for a splash guard on certain walls
arose .... so  I went polyhedron.....

i noticed that my polyhedron had some funny features depending on the
angle looking onto it, but on compiling it didn't complain AFAIK.....

for the hole i still tried to go 2D first, with a lot of pain to my old
brain, i finally managed to get a centered and working hex grid....
extruded it and diffed it with the polyhedron, and now it looks frankly
weird..... nearly all of the polyhedron is gone and compiling well i get
the dreaded mesh is not closed.....

integrating the hexes directly into the polyhedron will be a major pain
considering my incompetence...  So if someone might be kind enough to point
out what I did wrong?

--
ciao
Bruno

---==========
http://nohkumado.eu/, http://bboett.free.frhttp://aikido.nohkumado.eu/,
http://bboett.free.fr
http://aikido.zorn.free.fr

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hello!
Once again something that looked fairly simple in the start got to a
huge headache....

i hope the attachment goes through, there you can see my actual tries
to get this working....
it started by wanting to remix a nice fountain found on thingieverse,
but where the sizes were just so wrong for me that my available pump
didn't fit into it....

So I needed some slanted outer walls, and pierced inner walls, since
the theme was hexagons, I did everything in hexagons.....

I started by using cubes, but the slanting didn't go too well.... so
I started with a polygon, but the need for a splash guard on certain
walls arose .... so  I went polyhedron.....

i noticed that my polyhedron had some funny features depending on the
angle looking onto it, but on compiling it didn't complain AFAIK.....

for the hole i still tried to go 2D first, with a lot of pain to my
old brain, i finally managed to get a centered and working hex
grid.... extruded it and diffed it with the polyhedron, and now it
looks frankly weird..... nearly all of the polyhedron is gone and
compiling well i get the dreaded mesh is not closed.....

integrating the hexes directly into the polyhedron will be a major
pain considering my incompetence...  So if someone might be kind
enough to point out what I did wrong?

--
ciao
Bruno

---==========
http://nohkumado.eu/, http://aikido.nohkumado.eu/,
http://aikido.zorn.free.fr

OpenSCAD mailing list
To unsubscribe send an email to discuss-leave@lists.openscad.org

On Sun, 2023-12-17 at 23:04 +0100, Bruno Boettcher via Discuss wrote:
So is it a cube with slanted walls, perforated with hexagons?
If so, try something like this.

difference() {
hull() {
cube ([30,200,0.1], center=true);
translate ([0,0,200]) cube([26,190,0.1],center=true);
}
translate ([0,75,20])hexagon();
}

module hexagon() {
rotate([0,0,0])rotate([90,0,90])
#cylinder(50,18,18,center=true,$fn=6);
}

Is this you are looking for?
Screenshot 2023-12-18 at 7.38.57 AM.png

python code for the same is in the left window

For those that don't want python extensions, the honeycomb pattern in 
pure OpenSCAD.

// Parameters
blockX = 300;
blockY = 500;
blockZ = 50;
WallThickness = 2;
cellSize = 50;                           // cell diameter measured from vertex to opposite vertex (when wall has zero thickness).

// Derived values used for construction
dHex = cellSize * sin(60);               // distance between cell centres
tileX = 2 * dHex * sin(60);              // honeycomb repetition distance in X
tileY = 2 * dHex;                         // honeycomb repetition distance in Y

// 2D honeycomb is made by repeating these 2D rectangular tiles
module tile() {
   difference() {
      square([tileX, tileY], center = true);
      for(i = [30 : 60 : 330]) translate([dHex * cos(i), dHex * sin(i)]) circle(d = cellSize - WallThickness, $fn = 6);
      circle(d = cellSize - WallThickness, $fn = 6);
   }
}

// lay out enough tiles for size of block then crop to exact size and extrude to desired block height
linear_extrude(blockZ) intersection() {
   rows = ceil(blockY / tileY);
   columns = ceil(blockX / tileX);
   for(a = [-columns / 2 : columns / 2]) for (b = [-rows / 2 : rows / 2]) translate([a * tileX, b * tileY]) tile();
   square([blockX - 2 * WallThickness, blockY - 2 * WallThickness], center = true);
}

// add block wall
linear_extrude(blockZ) difference() {
   square([blockX, blockY], center = true);
   square([blockX - 2 * WallThickness, blockY - 2 * WallThickness], center = true);
}

hello!
Once again something that looked fairly simple in the start got to a
huge headache....

i hope the attachment goes through, there you can see my actual tries
to get this working....
it started by wanting to remix a nice fountain found on thingieverse,
but where the sizes were just so wrong for me that my available pump
didn't fit into it....

So I needed some slanted outer walls, and pierced inner walls, since
the theme was hexagons, I did everything in hexagons.....

I started by using cubes, but the slanting didn't go too well.... so I
started with a polygon, but the need for a splash guard on certain
walls arose .... so  I went polyhedron.....

i noticed that my polyhedron had some funny features depending on the
angle looking onto it, but on compiling it didn't complain AFAIK.....

for the hole i still tried to go 2D first, with a lot of pain to my
old brain, i finally managed to get a centered and working hex
grid.... extruded it and diffed it with the polyhedron, and now it
looks frankly weird..... nearly all of the polyhedron is gone and
compiling well i get the dreaded mesh is not closed.....

integrating the hexes directly into the polyhedron will be a major
pain considering my incompetence...  So if someone might be kind
enough to point out what I did wrong?

--
ciao
Bruno

---==========
http://nohkumado.eu/,
http://bboett.free.frhttp://aikido.nohkumado.eu/,
http://bboett.free.fr
http://aikido.zorn.free.fr

OpenSCAD mailing list
To unsubscribe send an email todiscuss-leave@lists.openscad.org

Today, Ray and I both posted code to make a honeycomb / hex grid. Ray's
approach is to simply subtract a load of hexagons from the required area.
Somehow my thought process took me down the route of defining a module that
creates a rectangular tile represents the basic repeat pattern, and then I
Iay down a bunch of my tiles.

It turns out that Ray's code renders much faster than mine. I suspect the
difference is that my version is repeatedly using a module, and perhaps the
module calculations are being repeated over and over, each time producing
an identical object That would certainly slow things down.

I have very little understanding of how OpenSCAD works internally but I
visualize it as using some kind of a hierarchic tree of objects. I did not
realize my module was going to be evaluated repeatedly. I realize that a
module with parameters likely needs to be recalculated, but I somehow
imagined that if there are no parameters involved there would be some kind
of copying of one branch of the tree to make another, thus avoiding
recalculation.

Okay, so now it seems to me that I was wrong in my assumption that a
modules would not always be recalculated. That's fine, but the mistake that
got me thinking ... would it be helpful to have a way to indicate to
OpenSCAD that a module only needs to be evaluated one time, and the
resulting object can simply be cloned on each subsequent use? (I guess I
could save the object generated by the module as an STL and then import the
STL for use over and over, but I'm asking about something I could do within
OpenSCAD.)

And, if there's no current way to do what I'm asking about, could it be
added in the future? Perhaps a special keyword to indicate that the object
generated on the first invocation can be cloned for all all other
invocations?

For today's example, it's easy enough to change how my program works to be
more like Ray's version, but I can image cases where a module is useful for
creating a complicated object but recalculating it for each instance is to
be avoided.

Steve

On 2023-12-18 8:30 a.m., Raymond West via Discuss wrote:

Hi,

Here's  my attempt, code attached below. .

Best wishes,

Ray
On 17/12/2023 22:04, Bruno Boettcher via Discuss wrote:

hello!
Once again something that looked fairly simple in the start got to a huge
headache....

i hope the attachment goes through, there you can see my actual tries to
get this working....
it started by wanting to remix a nice fountain found on thingieverse, but
where the sizes were just so wrong for me that my available pump didn't fit
into it....

So I needed some slanted outer walls, and pierced inner walls, since the
theme was hexagons, I did everything in hexagons.....

I started by using cubes, but the slanting didn't go too well.... so I
started with a polygon, but the need for a splash guard on certain walls
arose .... so  I went polyhedron.....

i noticed that my polyhedron had some funny features depending on the
angle looking onto it, but on compiling it didn't complain AFAIK.....

for the hole i still tried to go 2D first, with a lot of pain to my old
brain, i finally managed to get a centered and working hex grid....
extruded it and diffed it with the polyhedron, and now it looks frankly
weird..... nearly all of the polyhedron is gone and compiling well i get
the dreaded mesh is not closed.....

integrating the hexes directly into the polyhedron will be a major pain
considering my incompetence...  So if someone might be kind enough to point
out what I did wrong?

--
ciao
Bruno

---==========
http://nohkumado.eu/, http://bboett.free.frhttp://aikido.nohkumado.eu/,
http://bboett.free.fr
http://aikido.zorn.free.fr

OpenSCAD mailing list
To unsubscribe send an email to discuss-leave@lists.openscad.org

OpenSCAD mailing list
To unsubscribe send an email to discuss-leave@lists.openscad.org

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To unsubscribe send an email to discuss-leave@lists.openscad.org