solidboredom / constructive

Extends OpenScad Language for complex and complementary mechanical parts with less mathematical code. Offers a "Stamping" approach to quickly create mechanical parts fitting and complementing one another. This is used as a replacement for Constraints known form other CAD systems

License

This work is dual-licensed under GPL 2.0 or CERN-OHL-W .

You can choose between one of them if you use this work.

SPDX-License-Identifier: GPL-2.0 OR CERN-OHL-W

Constructive Library:

Extends OpenScad Language for complex and complementary mechanical parts with less mathematical code. Offers a "Stamping" approach to quickly create mechanical parts fitting and complementing one another. This is used as a replacement for Constraints known form other CAD systems Easily create holes from modules and overcome many Openscad's limitiations for complex models using the library's own syntax.

Compiles directly by OpenScad. No other tools needed. Just include the: constructive-compiled.scad in your .scad file, that is all.

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Constructive Library (about 1900 lines of Code) introduces a different approach to OpenScad Syntax: you rarely need difference(), for(),intersection() or their one-to-one equivalents, In the library's own dialect a for() block might look like:

pieces(4) X(every(35)) turnXY (vals(10,25,-15,40)) cube(10);

It is all valid OpenScad, you do not need any additional programs, just the OpenScad and the constructive-compiled.scad file.

The Constuctive-Syntax tries to align more with mechanical construction of parts and less with mathematical concepts like arrays, vectors and functions. (but they are heavily used behind the scenes). So it aims to be more concise and fluent for mechanical parts than vanilla OpenScad. It allows you to make holes from Modules and really good deal more.

NOTE: if you use a development version openscad, please make sure the experimental option "lazy Unions" is tuned off under Settings. This experiment breaks Openscads compatibility and you might encounter problems with this library also.

For a basic introduction (specially if you are new to Openscad ) see the beginners tutorial it explains Constructive Syntax for main Building blocks, like tube(), box() or bentStrip() and their placement and alignment in space like stack() , align(), X(),Y(),Z() or turnXZ()

Part II tutorial shows somee basic object modification like reflectX(), cScale() ,or colors and then goes on to explain, how to work with sets of similar objects without for(), with: pieces(), span(), vals(), selectPieces(), etc..

Part III tutorial shows more advanced Features like grouping commands into a g() group, working with Parts, and combinig them into Assembly

if you have questions you can ask me on the Openscad mailing list: https://lists.openscad.org/list/discuss.lists.openscad.org . Just add: constructive-lib to your subject to make sure i will see it

For a more advanced use also look at the explanations inside the example below

https://github.com/solidboredom/constructive/blob/main/examples/mount-demo.scad

there is also another Example at:

https://github.com/solidboredom/constructive/blob/main/examples/pulley-demo.scad

Note: Here A Gallery where some shiny constructive examples will be added, to show what can be acheived

https://github.com/solidboredom/constructive/blob/main/gallery/

Note: see here the source code ofthe Gallery pieces here: https://github.com/solidboredom/constructive/blob/main/gallery/sources/

how little code is actually needed for this, the code is in part not commented nor cleaned up, but it still can be used for reference

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The easiest way to try out the Library is to download the kickstart.zip

Still uncovered are inverse transformations like in:

g(X(10),Y(15),turnXY(45),X(30))

g(backwards([X(10),Y(15),turnXY(45),X(30)])

    box(10);

also part inheritance, part selector prefixes, internal type Ssystem and some more features

Try it! i hope you will find it as useful as i do.

Peter

constructive's Issues

`chamfer()` changes box dimensions?

box(2) gives a 2x2x2 box as expected (https://rjp.is/stls/nochambox2.stl)

chamfer(0,0,0) box(2) gives a 2x2x2.06 box (https://rjp.is/stls/cham0box2.stl)

chamfer(0, -0.1, -0.1) box(2) gives a 2x2x2.03 box
(https://rjp.is/stls/cham0101box2.stl).

Seems to stabilise at 2.03 as you increase those two values.

Oddly chamfer(-0.1, -0.3, -0.3) box(2) gives an exact 2x2x2 box (https://rjp.is/stls/cham010303.stl) - it seems that if the first value is not 0, you'll get the height you requested (even with a skirt chamfer.)

I can work around this by making my chamfered boxes a little taller than required and clipping them down but is there a way to get a chamfered top-and-sides box with an exact height?

(All measurements via stl_bbox from https://github.com/AllwineDesigns/stl_cmd.git )

Possible to license as GPL2.0+ for OpenSCAD playground?

Hi, I'd like to ship this cool library in the OpenSCAD playground but currently can't as GPL2 can't be shipped as GPL3 (as to why we ship as GPL3, see its LICENSE)

Switching your dual licensing to GPL2 "or later" + CERN-OHL-W would fix this and make your project more easily accessible :-)

( @t-paul FYI)

Consider dual licencing under CERN-OHL-S?

Hi,

This looks like a really cool project. I get that it is GPL licensed to make it strongly reciprocal. It does make it unclear if it can be used in open hardware projects that are also strongly reciprocal. The main strongly reciprocal open hardware license is the CERN OHL-S (v2).

Would you consider dual licensing for open hardware use?