Parsing values to children
It is nice that we have the ability to override the built-in modules on
OpenSCAD, however it seems to elude me how to parse any values the the
children of a module as is the case with the built-in for() loop where for
instance the variable i is available for the children of for(i=[1:5])
One way to come around this is to specify the iterator as a global variable
like in children($angle=angle) as I have done in the code snippet below
below, but this is not how for() loops work.
The reason I came about this is that I need the iterator of the
rotate_extrude() angle parameter to be exposed within its child matrix.
Consider the code below
//prototype for alternative rotate_extrude() exposing $angle as iterator
variable - segments are not joined
module alt_rotate_extrude(angle=360, convexity=2){
$fn=($fn==undef||$fn==0)?10:$fn;
echo($fn, angle)
for(angle=[0:360/$fn:angle]){
rotate([0, 0, angle])
rotate_extrude(angle=360/$fn, convexity = convexity)
children($angle=angle);
}
}
// snail shell (approximated seashell surface)
snail_shell();
module snail_shell(){
let(phi=(sqrt(5)+1)/2)
alt_rotate_extrude(angle=900, convexity=2, $fn=50)
let(v=pow(phi,$angle/200))
translate([v, 2.2v])
difference(){
circle(r=v, $fn=$fn);
circle(r=v0.9, $fn=$fn);
}
}
If one were to write their own for() module that is compatible with
existing code how would this be done/what would the code be like?
If this is indeed possible it would be really nice to have such reference
code snippets in the documentation along the built-ins.
Kharar
If I understand what you're trying to do (which is not at all certain) then
you just need to change
children($angle=angle);
into
$angle=angle;
children();
On Wed, Sep 20, 2023 at 12:05 PM Martin Axelsen kharar@gmail.com wrote:
It is nice that we have the ability to override the built-in modules on
OpenSCAD, however it seems to elude me how to parse any values the the
children of a module as is the case with the built-in for() loop where for
instance the variable i is available for the children of for(i=[1:5])
One way to come around this is to specify the iterator as a global
variable like in children($angle=angle) as I have done in the code snippet
below below, but this is not how for() loops work.
The reason I came about this is that I need the iterator of the
rotate_extrude() angle parameter to be exposed within its child matrix.
Consider the code below
//prototype for alternative rotate_extrude() exposing $angle as iterator
variable - segments are not joined
module alt_rotate_extrude(angle=360, convexity=2){
$fn=($fn==undef||$fn==0)?10:$fn;
echo($fn, angle)
for(angle=[0:360/$fn:angle]){
rotate([0, 0, angle])
rotate_extrude(angle=360/$fn, convexity = convexity)
children($angle=angle);
}
}
// snail shell (approximated seashell surface)
snail_shell();
module snail_shell(){
let(phi=(sqrt(5)+1)/2)
alt_rotate_extrude(angle=900, convexity=2, $fn=50)
let(v=pow(phi,$angle/200))
translate([v, 2.2v])
difference(){
circle(r=v, $fn=$fn);
circle(r=v0.9, $fn=$fn);
}
}
If one were to write their own for() module that is compatible with
existing code how would this be done/what would the code be like?
If this is indeed possible it would be really nice to have such reference
code snippets in the documentation along the built-ins.
Kharar
OpenSCAD mailing list
To unsubscribe send an email to discuss-leave@lists.openscad.org
Not so much, I guess I just want to avoid using global variables because
that is considered good practice in most programming languages.
I believe
children($angle=angle);
and
$angle=angle;
children();
is going to have the same effect in my case.
On Wed, 20 Sept 2023 at 22:37, Adrian Mariano avm4@cornell.edu wrote:
If I understand what you're trying to do (which is not at all certain)
then you just need to change
children($angle=angle);
into
$angle=angle;
children();
On Wed, Sep 20, 2023 at 12:05 PM Martin Axelsen kharar@gmail.com wrote:
It is nice that we have the ability to override the built-in modules on
OpenSCAD, however it seems to elude me how to parse any values the the
children of a module as is the case with the built-in for() loop where for
instance the variable i is available for the children of for(i=[1:5])
One way to come around this is to specify the iterator as a global
variable like in children($angle=angle) as I have done in the code snippet
below below, but this is not how for() loops work.
The reason I came about this is that I need the iterator of the
rotate_extrude() angle parameter to be exposed within its child matrix.
Consider the code below
//prototype for alternative rotate_extrude() exposing $angle as iterator
variable - segments are not joined
module alt_rotate_extrude(angle=360, convexity=2){
$fn=($fn==undef||$fn==0)?10:$fn;
echo($fn, angle)
for(angle=[0:360/$fn:angle]){
rotate([0, 0, angle])
rotate_extrude(angle=360/$fn, convexity = convexity)
children($angle=angle);
}
}
// snail shell (approximated seashell surface)
snail_shell();
module snail_shell(){
let(phi=(sqrt(5)+1)/2)
alt_rotate_extrude(angle=900, convexity=2, $fn=50)
let(v=pow(phi,$angle/200))
translate([v, 2.2v])
difference(){
circle(r=v, $fn=$fn);
circle(r=v0.9, $fn=$fn);
}
}
If one were to write their own for() module that is compatible with
existing code how would this be done/what would the code be like?
If this is indeed possible it would be really nice to have such reference
code snippets in the documentation along the built-ins.
Kharar
OpenSCAD mailing list
To unsubscribe send an email to discuss-leave@lists.openscad.org
Ah, that turns out to be version dependent. In the stable version
(2021.01) passing it as an arg to children() gives a warning and doesn't
propagate the parameter. In the dev version they seem to be equivalent.
There is no other mechanism for passing information into children from the
parent other than $ variables.
On Wed, Sep 20, 2023 at 4:48 PM Martin Axelsen kharar@gmail.com wrote:
Not so much, I guess I just want to avoid using global variables because
that is considered good practice in most programming languages.
I believe
children($angle=angle);
and
$angle=angle;
children();
is going to have the same effect in my case.
On Wed, 20 Sept 2023 at 22:37, Adrian Mariano avm4@cornell.edu wrote:
If I understand what you're trying to do (which is not at all certain)
then you just need to change
children($angle=angle);
into
$angle=angle;
children();
On Wed, Sep 20, 2023 at 12:05 PM Martin Axelsen kharar@gmail.com wrote:
It is nice that we have the ability to override the built-in modules on
OpenSCAD, however it seems to elude me how to parse any values the the
children of a module as is the case with the built-in for() loop where for
instance the variable i is available for the children of for(i=[1:5])
One way to come around this is to specify the iterator as a global
variable like in children($angle=angle) as I have done in the code snippet
below below, but this is not how for() loops work.
The reason I came about this is that I need the iterator of the
rotate_extrude() angle parameter to be exposed within its child matrix.
Consider the code below
//prototype for alternative rotate_extrude() exposing $angle as iterator
variable - segments are not joined
module alt_rotate_extrude(angle=360, convexity=2){
$fn=($fn==undef||$fn==0)?10:$fn;
echo($fn, angle)
for(angle=[0:360/$fn:angle]){
rotate([0, 0, angle])
rotate_extrude(angle=360/$fn, convexity = convexity)
children($angle=angle);
}
}
// snail shell (approximated seashell surface)
snail_shell();
module snail_shell(){
let(phi=(sqrt(5)+1)/2)
alt_rotate_extrude(angle=900, convexity=2, $fn=50)
let(v=pow(phi,$angle/200))
translate([v, 2.2v])
difference(){
circle(r=v, $fn=$fn);
circle(r=v0.9, $fn=$fn);
}
}
If one were to write their own for() module that is compatible with
existing code how would this be done/what would the code be like?
If this is indeed possible it would be really nice to have such
reference code snippets in the documentation along the built-ins.
Kharar
OpenSCAD mailing list
To unsubscribe send an email to discuss-leave@lists.openscad.org