Lengthening a series of lines in equal increments

jeff hammond

a rough go at doing this with a dynamic component…

select the line at the origin then Window -> Component Options…. change the "# of vertical lines per turn" option for immediate results..

i plotted the lines using this..
x = a(t) cos(t), y = a(t) sin(t)

which looks like this: (archimedean spiral)

jeff hammond

•

another method…

click pic -> bigger

curvishear is part of FredoTools..
http://forums.sketchucation.com/viewtopic.php?t=42089

curviLoft is here:
http://forums.sketchucation.com/viewtopic.php?t=28586

pilou

@Jeff
Shadowline on the ground of the Curvishear is very elegant! (middle drawing image)

Not possible to make a curve with it ? (maybe a script is yet existing ? )

jeff hammond

@unknownuser said:

@Jeff
Shadowline on the ground of the Curvyshear is very elegant! (middle drawing image)

Not possible to make a curve with it ?

hmm.. not that i know of.. would be neat if you could though..

(actually, you could probably project the geometry somehow?? i think there might even be a plugin that could do it?)

jeff hammond

[off:aznqnqp7]
@unknownuser said:

@unknownuser said:

@Jeff
Shadowline on the ground of the Curvyshear is very elegant! (middle drawing image)

Not possible to make a curve with it ?

hmm.. not that i know of.. would be neat if you could though..

(actually, you could probably project the geometry somehow?? i think there might even be a plugin that could do it?)

set sun directly overhead to be used as a preview..
orient the helix to your liking using the shadow as a guide..
sandbox-> drape…

[/off:aznqnqp7]

pilou

So that was simple!
I will try that because seems too simple for to be true!

About the first problem
I am waiting the Sdmitch autorization
for calculate a serie of lines not in equal increment

pilou

@Jeff
I'm very bored for testing your genious trick!

Very Curious I can't have the open of the all menu of a Shadow settings box dialog!
I don't have the same Shadow settings
From your Shadows settings image

And this don't open something more! (V6 or V7)
Shadow tool is enable on the Toolsbar list menu!

Seems i had this box dialog in the past

No more in Style / Edges

The button Activate Shadow dialog seems makes nothing!
No more in selecting curve right click
No more Entity Info, Model info... Cast Shadows, Receive Shadows are enable

Maybe I miss something or a plug squize this function ?

pilou

So for the lines in not equal alignement

make each lines as component (see follow how do make that)
(there are the Target)

redraw the same number of lines in equal alignement
use any method above for modify them
make each these new lines as a components (there are the Source)
(see follow how do make that)

use this tricky new plugin of Sdmitch who permit now replace components Source--> Target
Randomly or Not ! So choose No

See this post for precision of the normal use of the Replace Components

And maybe a plug(s) for make each (original lines / new lines) a component
Select a familly of lines
Loose geometry to groups by Chris Fullmer
Then Groups to components TT by Thomthom

That all!

ComponentReplacement.rb

jeff hammond

hmm.. i don't know what to tell you.. it's not a plugin.. just standard sketchup settings.

does someone with windows know about this?

once you get that part figure out, you'll also want to go Model Info -> Geo Location -> Set Manual Location
then set the latitude to 0º
this will make it possible to have the sun directly over head.. then adjust the time of day settings to fine tune it..
(use Top View when lining it up)

pilou

@unknownuser said:

it's not a plugin.

Of course that is not a plugin, it's just a dialog box

But I have tested that is not a plugin who blocks this Menu function!
Maybe a file has desapeared

Or maybe that is a "Pro version" function ?

Docs
From the Doc

@unknownuser said:

Activate the Shadow Settings dialog box from the Window menu.

Made but no Box dialog appears!
I will try on V8 tomorrow

jeff hammond

`

another approach:

click pic -> bigger

(Jim) DrawHelix:
http://forums.sketchucation.com/viewtopic.php?t=33139

(TIG) Extrude Edges by Object to Vector to Object:
http://forums.sketchucation.com/viewtopic.php?t=37515

download the ExtrudeEdges suite here:
http://forums.sketchucation.com/viewtopic.php?p=217663#p217663

pilou

@Jeff
on an other computer with V 6,7,8 free your tricky tip works like a charm!

So I believe problem should maybe about open "Shadows dialog box" for mysterious reasons!

sdmitch

@davecon said:

Thanks for the help so far everyone

I have got the hang of doing this on a straight line, now the complex bit is trying to do it on a spiral. Currently I am trying to turn the model on the left (spiral with even length lines) in the model on the right (spiral with lines increasing by XX per length)
[attachment=1:2ramdbm4]spiral lines.jpg[/attachment:2ramdbm4]

Ideally what I would like to be able to do is select the first line (red) and then the last line (green) and be able to input something like "starting the with the first line make all the others increase in XXmm increments"

Here is the file itself so far.
[attachment=0:2ramdbm4]spiral lines.skp[/attachment:2ramdbm4]

Instead of going to the trouble of creating the equal length lines then extending them incrementally, I would make the "baseline", be it a flat spiral or a straight line divided into the desired number of segments, into a curve using weld and then you can create the lines originating from the curve's vertices.

The code to do this is as simple as this

mod = Sketchup.active_model
ent = mod.entities
sel = mod.selection
if !sel.empty? && sel.first.curve
 vers=sel.first.curve.vertices
# d is initial length, i is the increment, and a is the direction vector
 d=875.0.mm;i=87.5.mm;a=[0,0,-1]
 for v in vers
  p=v.position;pp=p.offset(a,d)
  ent.add_line(p,pp)
  d += i
 end
else
 UI.messagebox "select a curve"
end

It would be a monumental task to try to figure out the order of the equal length lines. When you select a group of anything, there is no guaranty that Sketchup will add them to the selection in the proper order. At least that has been my experience.