Talk:Profile Based Shapes

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The Profile Based Shapes page is intended to categorise profile based shapes systematically, not to match certain tool names but to describe them in a descriptive geometry/mathematical/technical sense.

Who is the target audience? I suppose beginners to average users of FreeCAD. I don't think they are interested in example "1.2.3.2.5", that is the stuff that belong in a scientific dissertation or a Wikipedia article, not in the FreeCAD Wiki. --Roy 043 (talk) 10:05, 10 December 2023 (UTC)
The terms Extrude, Revolve, Sweep and Loft are standard in the CAD industry. For example AutoCAD has a Rotate command (similar to Draft_Rotate) and a Revolve command. If you use "Rotate" instead of "Revolve" you are creating confusion where you should strive for the opposite. --Roy 043 (talk) 10:05, 10 December 2023 (UTC)
Since CAD modelling is recreating/simulating real world parts - existing or to be existing in the future - we should be able to name the geometrical parts that we use to create our models; and they differ from the tool names. So this is rather a bridge from technically correct expressions to the tool (and objects) names used in FreeCAD. This is far from being scientific. It is for any user who wonders why they have to use Pad or Extrude to crate prismatic parts or Sweep to simulate extruded and then bent parts. That is confusing!
The example below is to show that some sets of specialised object are just a subset of a more generic set. There should be a better way to express this relation than by this numbering but that is a task for the real page/TOC.
I doubt that there is something like a CAD industry even though it is quite often referred to in the forum. It is just a few companies providing applications for several industries, initially aiming at workflows that dinos like me were used to before the aid of computers. RD terminology was still matching with work shop terminology, but that is history since modellers speech uses the names of CAD objects and tools rather than geometric figures or "old fashioned" technical terms. I thought it would be a good idea to re-establish the relations between geometric figures, real world parts, workshop terminology, and finally linking to tool names.
If you feel this is too scientific for the average user of this wiki spare my time and delete this page immediately without further note. I'll concentat on other topics then. --FBXL5 (talk) 16:56, 10 December 2023 (UTC)


An object tree from general down to special could look like this:

1. Objects made of several various profiles
1.1. Objects made of several various profiles without a spine: Loft objects
1.1.1. Loft objects made of several various profiles
1.1.1.1. Loft objects made of exactly two different profiles
1.1.2. Loft objects made of several invariable profiles
1.1.2.1. Loft objects made of exactly two identical profiles
1.2. Objects made of one primary profile and a spine
1.2.1. Objects made of one primary profile and a spine with variable cross-section
1.2.1.1. Objects made of one primary profile and a spine using guide curves to control the variable cross-section
1.2.1.2. Objects made of one primary profile and a spine using several secondary profiles to control the variable cross-section
Trumpet pipes, pyramids
1.2.2. Objects made of one primary profile and a spine with invariable cross-section: Sweep objects
1.2.2.1. Sweep objects having a 3D curved spine using a 3D guide curve to control the alignment of the cross-section
Sealing profiles, (railway) rails
1.2.2.2. Sweep objects having a 2D curved spine using implicit rules to control the alignment of the cross-section
Hoses, pipes, air ducts
1.2.2.2.1 Sweep objects having a circle or an arc as spine using implicit rules to control the alignment of the cross-section: Rotated objects
Toroids, cones, rims, rings
1.2.2.2.2 Sweep objects having a straight line as spine using implicit rules to control the alignment of the cross-section: Prismatic objects
Cylinder, cuboids


Still a question: Are sweep object, and rotated object proper terms regarding descriptive geometry? (Or are swept object, turned/revolved object better choices?)