Ticket #5995 - Show spiral length in the property editor (was: Length of a spiral)

[bzb.dev001]

Using the Part wb. I've created a spiral. Is there a quick way of finding the length of the spiral.

0.png (30.59 KiB) Viewed 1704 times

[vocx]

Using the Part wb. I've created a spiral. Is there a quick way of finding the length of the spiral.

I'm surprised that the length of the spiral object is not shown in the property editor. I think it should be.

All topological shapes have certain properties. You can inspect them from the Python terminal.

Use the selection view to get the Python object in the terminal, then inspect the Shape.

Code: Select all

obj.Shape.Length
# or
App.ActiveDocument.Spiral.Shape.Length

You can also inspect other properties like

Code: Select all

obj.Shape.Area # for faces
obj.Shape.Volume # for solids
obj.Shape.Vertexes # points in the shape
obj.Shape.Edges # lines that make the shape
# and others

[pl7i92LCNC]

there shoudt be a general inspection tool in the workbenches

[thschrader]

there shoudt be a general inspection tool in the workbenches

It is...
arch-wb, survey-tool

spiral_survey_tool.JPG (81.29 KiB) Viewed 1662 times

[Kunda1]

issue #4159 was opened regarding this issue.

[chennes]

I'm surprised that the length of the spiral object is not shown in the property editor. I think it should be.

issue #4159 was opened regarding this issue.

Is there precedent for this feature elsewhere in FreeCAD? I was looking into implementing it, but actually none of the primitives in Part display any sort of Read-Only calculated geometrical information in the property editor, as far as I can see. If Length makes sense for Spiral, it probably makes sense for Line, too (for example). I ask in part because I was hoping to borrow the code from someplace else: it's easy enough to add an Output property to the list, but I don't actually know how to get OCCT to tell me the length of the spiral.

[Kunda1]

Ticket migrated to issue #5995

[adrianinsaval]

@chennes what's your take on the matter now? IMO if it's gonna be implemented here it should be implemented everywhere including other shape properties like area and volume for surfaces and solids respectively, otherwise just close the issue and keep this as a property obtained trough python.

It could potentially be shown in the property view as children of the shape property of every object that has it, showing Length (sum of all edges), Area (sum of all faces) and Volume (sum of all solids). Not sure how to manage compounds.

[chennes]

Well, I personally would love an easy, GUI-based way to get basic stats about selected entities like this -- but my original question stands, about whether there is any precedent for this in FreeCAD. Of course we have read-only properties, but what about displaying calculated properties like this?

[adrianinsaval]

At the very least I know there are properties calculated from other properties in an object in PD Helix (and which property is calculated changes depending on the Mode), don't know if there is any calculated from shapes.