Getting Component Size with Ruby

[Aibonewt]

Okay,

I've been lurking here a while, but now it's time to raise my head above the parapet!

Been an AutoCAD user for about 25 years and coded various widgets in AutoLISP, Visual Basic (and a bit of C/Arduino), and I'd really like to get started with Ruby.

I've already built a few DCs from the GUI, quite happy with building parametric components and even building simple models from Ruby, but here's the problem...

Is there any way to get dimensions (lenx/y/z) values without setting attributes?

If I make a box, and convert it into a component called 'Box', about the only thing I can get from Ruby is it's name. Lenx for example, returns zero until I go to the GUI and add the attribute manually. Is there any way to set attributes to their default so they can be read by Ruby?

If I use an attribute explorer, I can see real dimensions in _last_lenx/y/z so theymust be readable somehow?

Many thanks in advance!

[kaas]

Getting the size of an element with Ruby can be done with the boundingbox method.
http://www.sketchup.com/intl/en/developer/docs/ourdoc/boundingbox

Just get your box definition into a variable (for instance box_def) and use the methods
box_def = Sketchup.active_model.definitions["Box"] bbox = box_def.bounds w = bbox.width (same for depth and height)

[Aibonewt]

@kaas said:

Getting the size of an element with Ruby can be done with the boundingbox method.
http://www.sketchup.com/intl/en/developer/docs/ourdoc/boundingbox

Just get your box definition into a variable (for instance box_def) and use the methods
box_def = Sketchup.active_model.definitions["Box"] bbox = box_def.bounds w = bbox.width (same for depth and height)

Oh wow!

That works brilliantly, thank you!

The naming convention of width, depth and height seem the wrong way round but I can live with that. The code snippet below outputs the dimensions in the format 'name x y z'

# this lists component name and bounding box dimensions

model = Sketchup.active_model
entities = model.entities
entities.each { |entity|
  if entity.class == Sketchup;;ComponentInstance
    name = entity.definition.name
    defn = entity.definition
    bbox = defn.bounds
    w = bbox.width.to_l.to_s
    h = bbox.height.to_l.to_s
    d = bbox.depth.to_l.to_s
    puts name + " " + w + " " + h + " " + d
  end
}

P.S. Sorry about the thumbs down, I hit it by mistake and it wouldn't let me change it

[TIG]

You spotted the longstanding weirdness.

SketchUp, like many newer 3d modeling tools, uses the convention that you are looking through the screen at the 3d object, and the X/Red/width is left>right, Y/Green/depth is front>back and Z/Blue/height is down>up.

Some older 3d applications went down an alternative route.
These assume that you are looking down onto the object from above - since they evolved from simpler 2d applications where there was only X and Y to worry about - and Z was never considered at all.
Their convention is therefore that X/width is parallel to the screen's horizontal, Y/height is parallel to the screen's vertical, and Z/depth is out of the screen !
And that's why some import/export options in SketchUp ask if you want to flip Y and Z axes.
For example an OBJ file uses the alternative non-SketchUp convention.

For some reason [never explained] the guys who wrote the Bounds API code [years ago] followed the non-SketchUp regime, while the rest of the team followed the SketchUp schema... and so for evermore we have the confusion - the bb.width is X [as expected], BUT perversely the bb.height is Y and the bb.depth is Z. Authors have asked for aliases of the methods to be added to the API, but without success - if they were, bb.width ===> bb.x[_size], bb.height ===> bb.y[_size] and bb.depth ===> bb.z[_size] - then matching the other API usage...

But for now you'll just have to get used to the weirdness

[kaas]

@aibonewt said:

...That works brilliantly, thank you!...P.S. Sorry about the thumbs down, I hit it by mistake and it wouldn't let me change it

Glad to be of help. Np about the thumbs...
Also, nice TIG for your clarification. Already wondered.

[TBoy]

@aibonewt said:

@kaas said:

Getting the size of an element with Ruby can be done with the boundingbox method.
http://www.sketchup.com/intl/en/developer/docs/ourdoc/boundingbox

Just get your box definition into a variable (for instance box_def) and use the methods
box_def = Sketchup.active_model.definitions["Box"] bbox = box_def.bounds w = bbox.width (same for depth and height)

This Bounding Box includes rotation, so X, Y , Z sizes are not object sizes.

Is there a way to get exact sizes of objects (or groups,entities.. any kind of selection)according to local ("objects") or world coordinate system? (Sorry if my terminology is wrong).

[Lê Việt Trường]

@unknownuser said:

This Bounding Box includes rotation, so X, Y , Z sizes are not object sizes.

Is there a way to get exact sizes of objects (or groups,entities.. any kind of selection)according to local ("objects") or world coordinate system? (Sorry if my terminology is wrong).

Here is my solution:

b = instance.definition.bounds
t = instance.transformation
x = ((b.max.x-b.min.x) * t.xscale)
y = ((b.max.y-b.min.y) * t.yscale)
z = ((b.max.z-b.min.z) * t.zscale)

Hope it helps
Have fun!