MOving objects and sticky connections between them-can it be done with Ruby?

[DanRathbun]

@MiniMe

I am quite good with python.

Okay, you’re a programmer with OOP experience, so you should pick up Ruby quite quickly, as long long as you don’t expect Ruby to share some of Python’s quirks, … (ie, forced indentation blocks, … no end keywords, automatic modules having the filename’s name, etc.)

@MiniMe

I think it [ Sketchup level ] is good enough for what I need

Okay then … but … keep in mind …

SketchUp does not have true geometric layers (so deal with that.)
Does not have “lines”, it has 0 width edges (so you’d need to use edge style likely to give substance to the “connectors”.)
Does not have “sticky” connections (you’d have to fake it by assigning an attribute to an edge object that holds the persistent id of a component instance that it terminates to.)

@MiniMe

All I need is a routine to read the position of my objects and redraw the lines as needed.

It can be reactionary using observer(s). It is likely that moving any component instance will trigger the #onChangeEntity observer callback. In this, you can start a timer (allowing the current callback queue to finish,) then popup a messagebox asking to redraw the “connections”.

@MiniMe

It does not even need to be realtime, I can run it manually.

Doesn’t matter much as the “redraw” code would be in a common method called in both scenarios.
The drawing will need to leverage some factory methods of the Sketchup::Entities class.
To find objects you’ll need to learn to iterate this collection class using it’s iterator methods, and/or those mixed in from Ruby core’s Enumerable module (most especially the grep method.)
Also have posted examples here …

Selecting Specific Entity, Group or Component (By Name)

Very similar for groups, because groups are disguised components. That means they have definitions. And their definitions have a separate name attribute, than the group instances. But there are a few quirks. The group.description method is an wrapper for group.definition.description. (So like a component instance, they share their definition’s description attribute.) So to find groups through the definition list, we need to filter out the definitions for images and normal components. dlist …

To get center points you’ll need to use the Geom::BoundingBox class, returned by Drawingelement#bounds.

To move things around geometrically you’ll need to understand transformations.

To “tag” objects with data, you’ll attach and use an AttributeDictionary. Dictionaries are shared space objects, so they need to be uniquely named. I suggest the same qualification as the extension’s module nesting, but with the :: scope operator replaced with underscore …

dictname = Module::nesting[0].name.gsub(/(::)/,'_')

From within a module nested as … CompanyX::NiftyWidget
the dictionary name string would be "CompanyX_NiftyWidget"

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There is no magic wand I can wave and grant you the knowledge and ability.
You’ll just have to spend a week or two reading and studying extension examples.

I compiled a list of Ruby Learning links here in this forum …

• Ruby Learning Resources [WikiLists]

There are several examples of tools by the SketchUp Team in the Extension Warehouse.

This one is a must read:

• Extension | SketchUp Extension Warehouse

There are also others … Window Maker, Bezier Curve Tool, Rotate Rectangle Tool, etc.

Check out their extensions listing: Page Not Found | SketchUp Extension Warehouse