Transformation of single entities ???

artmusicstudio

hi,
again i cannot really find a solution in the api-description:

when i have a group of 100 entities (edges and faces) and i know, that entity(50) is always the one i have to transform (it is a face),

how can i MOVE this face (like with the mouse) , so that all connected edges and faces adapt automatically?

i have the distance, the vector and the number of the entity.

thanx for helping!
stan

slbaumgartner

@artmusicstudio said:

hi,
again i cannot really find a solution in the api-description:

when i have a group of 100 entities (edges and faces) and i know, that entity(50) is always the one i have to transform (it is a face),

how can i MOVE this face (like with the mouse) , so that all connected edges and faces adapt automatically?

i have the distance, the vector and the number of the entity.

thanx for helping!
stan

I can't give you a working code snippet, but I can advise you that this operation is a lot more complicated than it might seem on the surface. The API has transform methods only for Group and ComponentInstance because primitive objects don't have Transformations associated with them. The GUI engine knows how to move primitive Entities such as Faces and Edges around, but it does so by continuously revising the Point3d values in them. I believe there is no way to alter these values via the API; you have to delete the existing objects and redraw them. The GUI also knows how to find and maintain the connected Edges and Faces. Perhaps this capability would be a reasonable feature request for a future release of the API.

In pseudo-code, you want to:

get the Vertex positions of the Face you want to move
find all Edges and Faces connected to that Face
get the positions of the far end of each Edge emanating from a Vertex of your Face that is not one of the Face's own Edges
now delete your Face and all the Faces and Edges connected to it (!)
add your offset to the Vertex positions of your Face and redraw it.
redraw the Edges from each Vertex of your new Face to the corresponding original far end(s)
use the API to find the Faces associated with each Edge of your new Face

Not having coded it, I'm not 100% sure there aren't some flaws in that sequence, but it makes sense to me

Steve

jolran

You may also have to account for inner faceloops..

So I pass along a solution TIG gave me ages ago. The "face-clone". Don't know where it orginates from..
Anyway have worked perfect with faces with holes. It may serve as a startingpoint..

It does what slbaumgartner just mentioned more or less. Not deleting the original face though!

There are some recent threads as to why one have to rewrite the faceloops if having "holes", ~~but I can't relocate them..~~
http://sketchucation.com/forums/viewtopic.php?f=180%26amp;t=55238


# You will have to create and collect;
#gents = a new group which will be containing the face clone( group.entities )
#faces is a collection of original faces

faces2go=[]; 

faces.each{|face|
	face.loops.each{|loop|gents.add_face(loop.vertices)}   # make innerfaces and all faces
	oface = gents.add_face(face.outer_loop.vertices)       # make outer faces again to be sure
	gents.each{|face| 
		next if face.class!=Sketchup;;Face     
			face.edges.each{|e|
			if not e.faces[1]
			   break
			end
		faces2go << face
		}
	}
}

gents.erase_entities(faces2go)   #erase inner faces

BUT! Rereading the topic I wonder if you are not just wondering how to translate entities ?

The danger in that is that the original face & Id might get altered, and your reference to the original selection then get's lost.

Translating the face vertices "en masse" I'd think you should look into [highlight=#ff0000:wcl7fvpm]transform_by_vectors[/highlight:wcl7fvpm]
http://www.sketchup.com/intl/en/developer/docs/ourdoc/entities.php?hl=sv-SE#transform_by_vectors

TIG

Try something like this...
vector.length = distance tr = Geom::Transformation.translation(vector) face.parent.entities.transform_entities(tr, [face])
The 'face' [and its connecting edges/vertices] will be transformed by the 'vector', having set its length to 'distance'...
You can get the 'entities' context in several ways - this gets it from the 'face' container...

"entities.transform_by_vectors" needs matching arrays of vectors and objects [often vertices] - because all of the translations are the same in your case the "transform_entities" using a single 'translation-transformation' and a lone 'face' will suffice...

jolran

Ah, yeah it's only one face..
Then TIG's solution is more accurate.
Was wondering though, is the "output" the same between those 2 methods ?

Why I ask, is that I somehow was under impression that to avoid referencing to deleted or nil faces, since sometimes when translating faces the reference to a face in an Array may become deleted due to just that translation, cause some translations creates new faces etc. And to avoid that one use transform_by_vector.
(may not be relevant here since were only dealing with 1 face, but curious while at it )

edit: reffered to vertices when meant faces..

Or am I misslead ?

slbaumgartner

@tig said:

Try something like this...
vector.length = distance tr = Geom::Transformation.translation(vector) face.parent.entities.transform_entities(tr, [face])
The 'face' [and its connecting edges/vertices] will be transformed by the 'vector', having set its length to 'distance'...
You can get the 'entities' context in several ways - this gets it from the 'face' container...

"entities.transform_by_vectors" needs matching arrays of vectors and objects [often vertices] - because all of the translations are the same in your case the "transform_entities" using a single 'translation-transformation' and a lone 'face' will suffice...

I stand corrected and educated Never noticed that method on Entities. Thanks TIG.

Steve

artmusicstudio

hi everybody,
thanx for this interesting discussion,

and yes, tig's way worls perfectly, so it is possible to immitate the mouse movement of single entities in any angle and direction.
fantastic!



                new_line10 = entities31.add_line pts[1], pts[0]
		tr = Geom;;Transformation.rotation(pts_senkrecht1,@vector,@angle_m.degrees)
		group31.entities.transform_entities(tr, new_line10)

#MOVE 1 FACE  >>>> number
						
		distance_m_result = @carrier_w *@totaloffset_x_center/@run 
		vector2 = new_line10.line[1]
		vector2.length = distance_m_result.abs
		
		tr = Geom;;Transformation.translation(vector2)
		group31.entities.transform_entities(tr,group31.entities[number])

stan