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!