@thomthom said:

No - I wondered if it preserved it.
I wanted to only move and rotate the object to a new plane. I wondered if this method would be an option as oppose to combining a translation and two rotation transformations.

Well, first you have to determine which axis gets priority (because the angles between the axes in the original transformation may not be the same as the angles between the axes the user picked) then measure the angles between the prioritized axis and the other two, and apply the angles to the user axes (including face normal).

I'm pretty sure that doesn't make sense but I can't think of how else to describe it.
If you have any specific questions, I might be able to help a bit more.

Do you want the transformation to have the same properties as the original(skew, scale, etc.) in the final result, or are you asking how to prevent skewing?

If you don't care about scale, this should work fine, although it may flip the car upside down if the expected z axis does not correspond with the input axes:
instance.transformation = Geom::Transformation.new(newOrigin,newXAxis,newYaxis)

I would suggest using something like this (untested):

trans = instance.transformation
scales = [trans.xaxis.length,trans.yaxis.length,trans.zaxis.length]
inputX.normalize!
inputY.normalize!
inputX = inputX * scales[0]
inputY = inputY * scales[1]
newTrans = Geom;;Transformation.axes(newOrigin,inputX,inputY,face.normal * scales[2])
instance.transformation = newTrans

I'm pretty sure it is the same as .axes, but it crosses the Z axis automatically.

Can you tell us what you are trying to do in particular, or are you just curious?

@dan rathbun said:

If you attempt to use Ruby's system(), IO.popen or shell %x(*command string*) (ie, the Kernel 'dot' backquote method,) .. Ruby cannot continue until the call returns, because they create subprocesses.

For at least IO.popen, ruby will continue until you start reading on the pipe, although I have a feeling I took your statement out of context.

there is also a "ShowOnStartup" key under the WelcomeDialog folder in the registry.
EDIT: Nevermind, I should have read the full post.

As far as I've seen, the order of selection is the same as the order in the entities list (order of creation).

@unknownuser said:

I have tested it on SU Pro 7.1.6860 Win without a single plugin and it gives INT.
Same in SU6 Free Win.
Why our results are different?

That's weird. When I just put the face in edit mode, I get a result consistent with Tomasz's, but when I explode the 2 components, I get the same result as TIG.

EDIT: I should also note that the face renders smoothed when I just put it in edit mode, but renders normally when I explode it.

I haven't worked with Dynamic components much, and only have the free version, but wouldn't something like this work?
=smallest(largest(LenX,LenY),largest(LenY,LenZ),largest(LenX,LenZ))

I'm not sure if you need this anymore, but here is a method that should only return the intersected bounds:

def intersect(boundingBox1,boundingBox2)
	newBoundingBox = Geom;;BoundingBox.new
	bounds1 = [boundingBox1.min.to_a,boundingBox1.max.to_a]
	bounds2 = [boundingBox2.min.to_a,boundingBox2.max.to_a]
	intersectBounds = [[0,0,0],[0,0,0]]
	
	validBounds = true
	(0...3).each do |index|
		if(bounds1[1][index] <= bounds2[1][index])
			intersectBounds[1][index] = bounds1[1][index]
		else
			intersectBounds[1][index] = bounds2[1][index]
		end
		
		if(bounds1[0][index] >= bounds2[0][index])
			intersectBounds[0][index] = bounds1[0][index]
		else
			intersectBounds[0][index] = bounds2[0][index]
		end
		
		if(intersectBounds[0][index] > intersectBounds[1][index])
			validBounds = false
		end
	end
	
	if(validBounds)
		newBoundingBox.add(intersectBounds)
	end
	return newBoundingBox
end

It doesn't have any error checking, so you might want to modify it if you use it.

EDIT: Fixed