BOSL2’s turtle is my tool of choice for any time I need a path of connected lines and arcs. It’s much easier than math. On Sat, Mar 8, 2025 at 8:06 AM Adrian Mariano via Discuss < discuss@lists.openscad.org> wrote: > I had the impression that the poster wanted the math, not an answer....but > BOSL2's turtle command also has lines and arcs in one command. You can > pass the result to path_sweep with the profile of your choice. > > include<BOSL2/std.scad> > r=15; > stem=25; > angle=45; > path = turtle(["right", 90, > "arcright", r, 180+angle, > "untilx", 0, > "left", angle, > // "arcleft", 9, angle, > "move", stem], [r,0]); > stroke(path,width=2); > > It's easy to eliminate the sharp corner, though it does misalign the stem > with the center of the hook circle. > > [image: image.png] > [image: image.png] > > > On Sat, Mar 8, 2025 at 8:40 AM Guenther Sohler via Discuss < > discuss@lists.openscad.org> wrote: > >> Pythonscad path Extrude would be best Match. It has Lines and arcs in one >> command and you can even define the Cross section. >> >> Raymond West via Discuss <discuss@lists.openscad.org> schrieb am Sa., 8. >> März 2025, 14:34: >> >>> I've ignored what has gone before, and have this, pretty well >>> parametric. Wrt a practical hook, then this design fails, it is merely an >>> example of stringing together a list of points to get a solid shape, with >>> some variation. >>> >>> >>> >>> // Function to generate points on a circle's circumference >>> function pointcircle(d, a1, a2, s) = let( >>> radius = d / 2, >>> // Calculate the angular step and handle direction >>> angle_diff = (a2 - a1 + (a2 >= a1 ? 0 : 360)), >>> num_points = ceil(abs(angle_diff) / (360 / s)) >>> ) [for (i = [0 : num_points - 1]) >>> let(angle = a1 + i * angle_diff / (num_points - 1)) >>> [radius * cos(angle), radius * sin(angle), 0] >>> ]; >>> >>> module pointshull(list){ >>> for(k=[0:1:len(list)-2]){ >>> hull(){ >>> translate(list[k])sphere(w/2); >>> translate(list[k+1])sphere(w/2); >>> } >>> } >>> } >>> >>> module shape(){ >>> round=pointcircle(diam,sa,ea,res); >>> straight= [[0,es],[0,ss]]; >>> all= concat(straight,round); >>> pointshull(all); >>> } >>> >>> shape(); >>> >>> diam = 50; // diam of 'hook' >>> sa = 135; // start angle >>> ea = 0; // end angle >>> res = 200; // resolution for circle >>> ss = 35; // start of straight >>> w = 8; // diameter of 'wire' >>> >>> es = ss+40; // end of straight >>> $fn = res/8;// smaller = quicker >>> >>> >>> >>> If you want a square cross section, so you can easily fdm print, then do >>> it as 2d, and linear extrude. Using a $fn=4 or similar distorts the cross >>> section around the curve, since 'the cube' does not rotate as it follows >>> the path, so to speak. >>> >>> >>> On 07/03/2025 21:03, Raymond West via Discuss wrote: >>> >>> Probably best to work with points, and generate the polygon for the mid >>> section. You know the rh point at bottom of top piece ((3/2, 18.25) you can >>> use trig (sin & cos) to get the inner point of the 45 degree cut. You can >>> calculate the length of the middle section, (Pythagoras?) and the width >>> will be 3. You can generate the four points for the middle rectangle (or a >>> square based on the calculated length and 3) and calculate its position. ( >>> you have already found the two points needed. (atan2 and translate). You do >>> not need the lh, bottom point of the upper piece, (-3/2,18.25) since if you >>> use that you will get a tapered middle section, unless you do another >>> calculation to get one of the corners of the middle piece. >>> >>> You could write a generic script, where you enter the width and radius >>> and length of straight section, and produce the shape in whatever size you >>> want, merely by adjusting those three values. (or set the width and length >>> as a function of the radius, and then you only need to enter the radius) >>> On 07/03/2025 20:06, Mark Harrison via Discuss wrote: >>> >>> Here is a hook with a lower curved part and an upper straight part. How >>> can I calculate the proper dimension/position of the middle connecting >>> part? In this sample I visually positioned it by trial and error, but I >>> would like to learn how to calculate this. >>> >>> Pure SCAD, or a pointer to other code that might solve the geometry >>> appreciated. I am as interested in learning the general solution/principle >>> as I am in the practical solution to the problem. >>> >>> // looped lower portion of hook >>> difference() { >>> circle(d=30); >>> circle(d=24); >>> square(30); >>> rotate(45) square(30); >>> } >>> // visually drawn mid-portion of hook >>> #rotate(45) translate([0,12]) square([14,3]); >>> // straight upper portion of hook >>> translate([-3/2,18.25]) square([3,16]); >>> >>> [image: image.png] >>> >>> -- >>> Mark Harrison >>> marhar@gmail.com >>> >>> _______________________________________________ >>> 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 >>> >>> _______________________________________________ >>> 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 >> > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

Does Bosl2 Turtle also Support Moving in 3d Space ? Am Samstag, 8. März 2025 schrieb Father Horton via Discuss < discuss@lists.openscad.org>: > BOSL2’s turtle is my tool of choice for any time I need a path of > connected lines and arcs. It’s much easier than math. > > On Sat, Mar 8, 2025 at 8:06 AM Adrian Mariano via Discuss < > discuss@lists.openscad.org> wrote: > >> I had the impression that the poster wanted the math, not an >> answer....but BOSL2's turtle command also has lines and arcs in one >> command. You can pass the result to path_sweep with the profile of your >> choice. >> >> include<BOSL2/std.scad> >> r=15; >> stem=25; >> angle=45; >> path = turtle(["right", 90, >> "arcright", r, 180+angle, >> "untilx", 0, >> "left", angle, >> // "arcleft", 9, angle, >> "move", stem], [r,0]); >> stroke(path,width=2); >> >> It's easy to eliminate the sharp corner, though it does misalign the stem >> with the center of the hook circle. >> >> [image: image.png] >> [image: image.png] >> >> >> On Sat, Mar 8, 2025 at 8:40 AM Guenther Sohler via Discuss < >> discuss@lists.openscad.org> wrote: >> >>> Pythonscad path Extrude would be best Match. It has Lines and arcs in >>> one command and you can even define the Cross section. >>> >>> Raymond West via Discuss <discuss@lists.openscad.org> schrieb am Sa., >>> 8. März 2025, 14:34: >>> >>>> I've ignored what has gone before, and have this, pretty well >>>> parametric. Wrt a practical hook, then this design fails, it is merely an >>>> example of stringing together a list of points to get a solid shape, with >>>> some variation. >>>> >>>> >>>> >>>> // Function to generate points on a circle's circumference >>>> function pointcircle(d, a1, a2, s) = let( >>>> radius = d / 2, >>>> // Calculate the angular step and handle direction >>>> angle_diff = (a2 - a1 + (a2 >= a1 ? 0 : 360)), >>>> num_points = ceil(abs(angle_diff) / (360 / s)) >>>> ) [for (i = [0 : num_points - 1]) >>>> let(angle = a1 + i * angle_diff / (num_points - 1)) >>>> [radius * cos(angle), radius * sin(angle), 0] >>>> ]; >>>> >>>> module pointshull(list){ >>>> for(k=[0:1:len(list)-2]){ >>>> hull(){ >>>> translate(list[k])sphere(w/2); >>>> translate(list[k+1])sphere(w/2); >>>> } >>>> } >>>> } >>>> >>>> module shape(){ >>>> round=pointcircle(diam,sa,ea,res); >>>> straight= [[0,es],[0,ss]]; >>>> all= concat(straight,round); >>>> pointshull(all); >>>> } >>>> >>>> shape(); >>>> >>>> diam = 50; // diam of 'hook' >>>> sa = 135; // start angle >>>> ea = 0; // end angle >>>> res = 200; // resolution for circle >>>> ss = 35; // start of straight >>>> w = 8; // diameter of 'wire' >>>> >>>> es = ss+40; // end of straight >>>> $fn = res/8;// smaller = quicker >>>> >>>> >>>> >>>> If you want a square cross section, so you can easily fdm print, then >>>> do it as 2d, and linear extrude. Using a $fn=4 or similar distorts the >>>> cross section around the curve, since 'the cube' does not rotate as it >>>> follows the path, so to speak. >>>> >>>> >>>> On 07/03/2025 21:03, Raymond West via Discuss wrote: >>>> >>>> Probably best to work with points, and generate the polygon for the mid >>>> section. You know the rh point at bottom of top piece ((3/2, 18.25) you can >>>> use trig (sin & cos) to get the inner point of the 45 degree cut. You can >>>> calculate the length of the middle section, (Pythagoras?) and the width >>>> will be 3. You can generate the four points for the middle rectangle (or a >>>> square based on the calculated length and 3) and calculate its position. ( >>>> you have already found the two points needed. (atan2 and translate). You do >>>> not need the lh, bottom point of the upper piece, (-3/2,18.25) since if you >>>> use that you will get a tapered middle section, unless you do another >>>> calculation to get one of the corners of the middle piece. >>>> >>>> You could write a generic script, where you enter the width and radius >>>> and length of straight section, and produce the shape in whatever size you >>>> want, merely by adjusting those three values. (or set the width and length >>>> as a function of the radius, and then you only need to enter the radius) >>>> On 07/03/2025 20:06, Mark Harrison via Discuss wrote: >>>> >>>> Here is a hook with a lower curved part and an upper straight part. >>>> How can I calculate the proper dimension/position of the middle connecting >>>> part? In this sample I visually positioned it by trial and error, but I >>>> would like to learn how to calculate this. >>>> >>>> Pure SCAD, or a pointer to other code that might solve the geometry >>>> appreciated. I am as interested in learning the general solution/principle >>>> as I am in the practical solution to the problem. >>>> >>>> // looped lower portion of hook >>>> difference() { >>>> circle(d=30); >>>> circle(d=24); >>>> square(30); >>>> rotate(45) square(30); >>>> } >>>> // visually drawn mid-portion of hook >>>> #rotate(45) translate([0,12]) square([14,3]); >>>> // straight upper portion of hook >>>> translate([-3/2,18.25]) square([3,16]); >>>> >>>> [image: image.png] >>>> >>>> -- >>>> Mark Harrison >>>> marhar@gmail.com >>>> >>>> _______________________________________________ >>>> 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 >>>> >>>> _______________________________________________ >>>> 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 >>> >> _______________________________________________ >> OpenSCAD mailing list >> To unsubscribe send an email to discuss-leave@lists.openscad.org >> > -- Null

Moving in 3D is substantially more complicated because you need to track not just position and direction but also roll, so a completely separate turtle3d() command exists for this purpose, which is able to return a list of transformation matrices instead of just a path. https://github.com/BelfrySCAD/BOSL2/wiki/turtle3d.scad On Sat, Mar 8, 2025 at 11:19 AM Guenther Sohler via Discuss < discuss@lists.openscad.org> wrote: > Does Bosl2 Turtle also Support Moving in 3d Space ? > > Am Samstag, 8. März 2025 schrieb Father Horton via Discuss < > discuss@lists.openscad.org>: > >> BOSL2’s turtle is my tool of choice for any time I need a path of >> connected lines and arcs. It’s much easier than math. >> >> On Sat, Mar 8, 2025 at 8:06 AM Adrian Mariano via Discuss < >> discuss@lists.openscad.org> wrote: >> >>> I had the impression that the poster wanted the math, not an >>> answer....but BOSL2's turtle command also has lines and arcs in one >>> command. You can pass the result to path_sweep with the profile of your >>> choice. >>> >>> include<BOSL2/std.scad> >>> r=15; >>> stem=25; >>> angle=45; >>> path = turtle(["right", 90, >>> "arcright", r, 180+angle, >>> "untilx", 0, >>> "left", angle, >>> // "arcleft", 9, angle, >>> "move", stem], [r,0]); >>> stroke(path,width=2); >>> >>> It's easy to eliminate the sharp corner, though it does misalign the >>> stem with the center of the hook circle. >>> >>> [image: image.png] >>> [image: image.png] >>> >>> >>> On Sat, Mar 8, 2025 at 8:40 AM Guenther Sohler via Discuss < >>> discuss@lists.openscad.org> wrote: >>> >>>> Pythonscad path Extrude would be best Match. It has Lines and arcs in >>>> one command and you can even define the Cross section. >>>> >>>> Raymond West via Discuss <discuss@lists.openscad.org> schrieb am Sa., >>>> 8. März 2025, 14:34: >>>> >>>>> I've ignored what has gone before, and have this, pretty well >>>>> parametric. Wrt a practical hook, then this design fails, it is merely an >>>>> example of stringing together a list of points to get a solid shape, with >>>>> some variation. >>>>> >>>>> >>>>> >>>>> // Function to generate points on a circle's circumference >>>>> function pointcircle(d, a1, a2, s) = let( >>>>> radius = d / 2, >>>>> // Calculate the angular step and handle direction >>>>> angle_diff = (a2 - a1 + (a2 >= a1 ? 0 : 360)), >>>>> num_points = ceil(abs(angle_diff) / (360 / s)) >>>>> ) [for (i = [0 : num_points - 1]) >>>>> let(angle = a1 + i * angle_diff / (num_points - 1)) >>>>> [radius * cos(angle), radius * sin(angle), 0] >>>>> ]; >>>>> >>>>> module pointshull(list){ >>>>> for(k=[0:1:len(list)-2]){ >>>>> hull(){ >>>>> translate(list[k])sphere(w/2); >>>>> translate(list[k+1])sphere(w/2); >>>>> } >>>>> } >>>>> } >>>>> >>>>> module shape(){ >>>>> round=pointcircle(diam,sa,ea,res); >>>>> straight= [[0,es],[0,ss]]; >>>>> all= concat(straight,round); >>>>> pointshull(all); >>>>> } >>>>> >>>>> shape(); >>>>> >>>>> diam = 50; // diam of 'hook' >>>>> sa = 135; // start angle >>>>> ea = 0; // end angle >>>>> res = 200; // resolution for circle >>>>> ss = 35; // start of straight >>>>> w = 8; // diameter of 'wire' >>>>> >>>>> es = ss+40; // end of straight >>>>> $fn = res/8;// smaller = quicker >>>>> >>>>> >>>>> >>>>> If you want a square cross section, so you can easily fdm print, then >>>>> do it as 2d, and linear extrude. Using a $fn=4 or similar distorts the >>>>> cross section around the curve, since 'the cube' does not rotate as it >>>>> follows the path, so to speak. >>>>> >>>>> >>>>> On 07/03/2025 21:03, Raymond West via Discuss wrote: >>>>> >>>>> Probably best to work with points, and generate the polygon for the >>>>> mid section. You know the rh point at bottom of top piece ((3/2, 18.25) you >>>>> can use trig (sin & cos) to get the inner point of the 45 degree cut. You >>>>> can calculate the length of the middle section, (Pythagoras?) and the width >>>>> will be 3. You can generate the four points for the middle rectangle (or a >>>>> square based on the calculated length and 3) and calculate its position. ( >>>>> you have already found the two points needed. (atan2 and translate). You do >>>>> not need the lh, bottom point of the upper piece, (-3/2,18.25) since if you >>>>> use that you will get a tapered middle section, unless you do another >>>>> calculation to get one of the corners of the middle piece. >>>>> >>>>> You could write a generic script, where you enter the width and radius >>>>> and length of straight section, and produce the shape in whatever size you >>>>> want, merely by adjusting those three values. (or set the width and length >>>>> as a function of the radius, and then you only need to enter the radius) >>>>> On 07/03/2025 20:06, Mark Harrison via Discuss wrote: >>>>> >>>>> Here is a hook with a lower curved part and an upper straight part. >>>>> How can I calculate the proper dimension/position of the middle connecting >>>>> part? In this sample I visually positioned it by trial and error, but I >>>>> would like to learn how to calculate this. >>>>> >>>>> Pure SCAD, or a pointer to other code that might solve the geometry >>>>> appreciated. I am as interested in learning the general solution/principle >>>>> as I am in the practical solution to the problem. >>>>> >>>>> // looped lower portion of hook >>>>> difference() { >>>>> circle(d=30); >>>>> circle(d=24); >>>>> square(30); >>>>> rotate(45) square(30); >>>>> } >>>>> // visually drawn mid-portion of hook >>>>> #rotate(45) translate([0,12]) square([14,3]); >>>>> // straight upper portion of hook >>>>> translate([-3/2,18.25]) square([3,16]); >>>>> >>>>> [image: image.png] >>>>> >>>>> -- >>>>> Mark Harrison >>>>> marhar@gmail.com >>>>> >>>>> _______________________________________________ >>>>> 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 >>>>> >>>>> _______________________________________________ >>>>> 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 >>>> >>> _______________________________________________ >>> OpenSCAD mailing list >>> To unsubscribe send an email to discuss-leave@lists.openscad.org >>> >> > > -- > Null > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

Yes https://github.com/BelfrySCAD/BOSL2/wiki/turtle3d.scad On 3/8/2025 11:19 AM, Guenther Sohler via Discuss wrote: > Does Bosl2 Turtle also Support Moving in 3d Space ? > -- This email has been checked for viruses by AVG antivirus software. www.avg.com