3D Designer
Modules
At some point, things are going to get complex. You are going to have objects twisted around other objects, modifying other objects that are used in combination with yet more objects.
It helps then that openSCAD supports modules to organize stuff. Modules are simply a bunch of instructions that go together.
To illustrate how they work, let's make a funnel as shown in Figure 7.
A funnel is made up by two parts: a hollow, cut-off conical object that I am going to call the hat (I couldn't find formal names for the parts of a funnel, so I am improvising here), and a hollow cylinder I am calling the pipe.
Turns out both the hat and the pipe can be made entirely from cylinders, since the hat, for openSCAD, is a cylinder with two different diameters at each end. As you need it to be hollow, you make another cylinder with a slightly smaller radius at both ends and subtract that from the bigger one. The module for that would look like Listing 3.
Listing 3
Hat Module
module hat () { difference () { cylinder (r1=8, r2=2, h=10, center=true, $fn=50); cylinder (r1=7.5, r2=1.5, h=10, center=true, $fn=50); } }
The pipe module is even simpler (Listing 4), but you do have to remember to translate the lower end of the pipe to the top of the hat (line 2).
Listing 4
Pipe Module
01 module pipe () { 02 translate ([0,0,10]) { 03 difference () { 04 cylinder (r=2, h=10, center=true, $fn=50); 05 cylinder (r=1.5, h=10, center=true, $fn=50); 06 } 07 } 08 }
With these two modules, you can create a funnel ()
module that calls the other two (Listing 5, lines 17 to 20). Then call the funnel ()
module to actually show something in the preview pane (Listing 5, line 22).
Listing 5
funnel.scad
01 module hat () { 02 difference () { 03 cylinder (r1=8, r2=2, h=10, center=true, $fn=50); 04 cylinder (r1=7.5, r2=1.5, h=10, center=true, $fn=50); 05 } 06 } 07 08 module pipe () { 09 translate ([0,0,10]) { 10 difference () { 11 cylinder (r=2, h=10, center=true, $fn=50); 12 cylinder (r=1.5, h=10, center=true, $fn=50); 13 } 14 } 15 } 16 17 module funnel () { 18 hat (); 19 pipe (); 20 } 21 22 funnel ();
You can take this modularity further and save a set of modules into a separate .scad file altogether. You can then import them back into other files using either the include
or the use
methods.
The include </path/to/file.scad>
method imports the whole thing, modules and commands that are not in modules, integrating the whole imported file into your current file. The use </path/to/file.scad>
method, on the other hand, only imports the modules so you can use them as library modules with the code in your current file.
This means that, to get a funnel with include
, all you have to do is:
include <funnel.scad>;
To do the same with use
, you would also have to call the funnel ()
method like this:
use <funnel.scad>; funnel ();
Conclusion
This article has covered the most essential bits and pieces of the OpenSCAD language. With this and the user manual's excellent documentation [5], you should be able to start creating your first 3D pieces.
That said, there is quite a lot more to learn regarding OpenSCAD. We'll be looking at more advanced things in next month's issue. We will also be creating a real piece to print and showing how you can go all the way from concept to real physical object.
Until then, have fun!
Infos
- Thingiverse: https://www.thingiverse.com/
- Atelier: https://atelier.kde.org/
- OpenSCAD: http://www.openscad.org
- FreeCAD: https://www.freecadweb.org/
- OpenSCAD User Manual: https://en.wikibooks.org/wiki/OpenSCAD_User_Manual
« Previous 1 2 3
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
TUXEDO Computers Unveils Linux Laptop Featuring AMD Ryzen CPU
This latest release is the first laptop to include the new CPU from Ryzen and Linux preinstalled.
-
XZ Gets the All-Clear
The back door xz vulnerability has been officially reverted for Fedora 40 and versions 38 and 39 were never affected.
-
Canonical Collaborates with Qualcomm on New Venture
This new joint effort is geared toward bringing Ubuntu and Ubuntu Core to Qualcomm-powered devices.
-
Kodi 21.0 Open-Source Entertainment Hub Released
After a year of development, the award-winning Kodi cross-platform, media center software is now available with many new additions and improvements.
-
Linux Usage Increases in Two Key Areas
If market share is your thing, you'll be happy to know that Linux is on the rise in two areas that, if they keep climbing, could have serious meaning for Linux's future.
-
Vulnerability Discovered in xz Libraries
An urgent alert for Fedora 40 has been posted and users should pay attention.
-
Canonical Bumps LTS Support to 12 years
If you're worried that your Ubuntu LTS release won't be supported long enough to last, Canonical has a surprise for you in the form of 12 years of security coverage.
-
Fedora 40 Beta Released Soon
With the official release of Fedora 40 coming in April, it's almost time to download the beta and see what's new.
-
New Pentesting Distribution to Compete with Kali Linux
SnoopGod is now available for your testing needs
-
Juno Computers Launches Another Linux Laptop
If you're looking for a powerhouse laptop that runs Ubuntu, the Juno Computers Neptune 17 v6 should be on your radar.