## [Plugin] Cyma Curve Tool

### [Plugin] Cyma Curve Tool

This Tool makes a classical 'Cyma' curve - see below for details...

THIS SOFTWARE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES,INCLUDING,WITHOUT LIMITATION,THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
###
CymaCurveTool.rb
###
Usage:
Choose 'Cyma Curve Tool' from the Plugins Menu;
or type 'cyma' in the Ruby Console...
###
Select parameters in the dialog, on OK the specified Cyma Curve
appears on the end of your cursor - place it where you wish...
The parameters are:
Overall Size X: The Horizontal size of the enclosing square -
default 100mm or 4" depending on model's units,
the last entered value is remembered with the model.
Overall Size Y: The Vertical size of the enclosing square -
default 100mm or 4" depending on model's units,
the last entered value is remembered with the model.
Chord Proportion:
The proportion of the Curve's Arc's Chord to its Radius.
There are two possibilities...
1: assuming a 'square form' [X==Y]...
For a basic Cyma it's sqrt(2) [1.4142136]
giving tangential springing points [90 degree].
For a "Palladian" Cyma it's 7/6 [1.1666666]
giving flattened arcs to the curve [the default].
The smaller the value the flatter the arcs, so 1 gives
equilateral arcs which can look too flat when viewed
from below; values <0.1 will given arcs so flat you
could have used straight lines! so 0.1 is the minimum.
You can enter values in decimal format [1.2345],
fractional format [7/6] or as 'sqrt' [sqrt(2)]
[note format with (nn) etc]
2: assuming a 'rectangular' form [X!=Y] the 90 degree
'tangential' form can be set by giving the
Chord to Radius proportion based on the formula
2*Y/sqrt(X*X+Y*Y)
so you can calculate this beforehand and enter it as
a decimal value, e.g. it's 0.8944 when X=200 & Y=100,
OR as it's also shown in the VCB prompt once the X & Y
values are set: to get it calculated for you, you make
a rectangular Cyma using the default value and then
immediately undo it, then rerun the tool - all of the
dialog's values are remembered, but the VCB prompt now
also shows the value that would give a tangential
90 degree form - so you can type that value into the
dialog and get 90 degree tangential springing points
for rectangular forms too.
Otherwise you can use the 7/6 or other values as
desired...
Curve Type: The two types of curve available are:
'Cyma Recta' - also called 'Gola'
[starts convex, ends concave] - it is the default type.
and
'Cyma Reversa' - also called 'Ogee'
[starts concave, ends convex]
Curve Format: You choose from the following:
'As Curve' - just the two arcs welded as a curve.
'As Curve with Face' - the two arcs welded as a curve
and their internal edges with a face -
useful for extrusions.
'As Curve with Guides' - the two arcs welded as a curve
with guide-lines and -points added to show the
arcs' centers etc.
Segments: Default is 36 - enter new value, must be 3 or more -
more segments give smoother curves BUT more geometry !
The geometry is in a Component named 'CymaCurve#1' or "CymaCurve#2"
etc for multiple versions...
Its description reflects its settings...
It is attached to your cursor by its bottom left corner
springing-point and it snaps to faces.
You can mirror it by using Scale -1 or Move/Copy it as desired,
or Explode as required...
###
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Wow TIG, I feel dumb just reading the descriptions of your plugins -- I know it muct be usefull, probably very usefull but I for the life of me could not figure it out.

Best,
Jason.
0
I create video tutorial series about several 2D & 3D graphics programs.

jason_maranto

### Re: [Plugin] Cyma Curve Tool

For stones carvers
0
Frenchy Pilou
Is beautiful that please without concept!
Speedy Galerie

pilou
Top SketchUcator

### Re: [Plugin] Cyma Curve Tool

From wikipedia:
"...The ogee curve is an analogue of a "cyma curve", the difference being that a cyma has horizontal rather than vertical ends..."

Not sure what is meant by horizontal v.s. vertical ends.
0
John | Illustrator | Beaverton, Oregon

JClements

### Re: [Plugin] Cyma Curve Tool

This is an ogee(the leftmost part of the image):

So I imagine a cyma curve is rotated 90 degrees.

Also useful for woodworkers...thanks TIG!

@JClements: I was going to post that exact same sentence from Wikipedia
0
3D Printing with SketchUp Book
http://goo.gl/f7ooYh

d12dozr
Top SketchUcator

### Re: [Plugin] Cyma Curve Tool

If you use the option to produce faces, the face extrudes with one "seam" along the cyma surface where the two arcs touch one another (can there be an option to "auto-weld" the two arcs?).

============================================
Peculiar arcs are drawn.

?? BUG: If you click on the "lower" arc, it is a polyline. However, if you click on any portion of the "upper" arc, only a segment is selected (of a the 36 defining the arc), yet it can extrude a smoothed surface. How can this be?
0
John | Illustrator | Beaverton, Oregon

JClements

### Re: [Plugin] Cyma Curve Tool

JClements wrote:?? BUG:... However, if you click on any portion of the "upper" arc, only a segment is selected (of a the 36 defining the arc), yet it can extrude a smoothed surface. How can this be?

I see that too...if you select one of the segments, actually 2 segments are selected - the one you chose as well as the segment at the end of the arc.
0
3D Printing with SketchUp Book
http://goo.gl/f7ooYh

d12dozr
Top SketchUcator

### Re: [Plugin] Cyma Curve Tool

Here's v1.1 viewtopic.php?p=230584#p230584
- FR lingvo by Pilou added.
- Faced option curves now welded as one so smooth extrusion without a mid-point join.
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

I'm looking at this 'BUG' where one of the arcs is in bits but still an arc ???
Update soonest...
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Here's v1.2 viewtopic.php?p=230584#p230584
The buggy second arc formation has been fixed - I simply made it a different way that now works - I think the problem had something to do with the curves being drawn the opposite directions but whatever it was it's now sorted ?
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Here's an explanation of the the 2 types of Cyma Curve...
cymas.png
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Here's v1.3 viewtopic.php?p=230584#p230584
Fixed a potential glitch from a missing 'require deB...'
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Thx TIG

You've done a pretty good Job. I'm sure you enjoy coding

MALAISE
0
La Connaissance n'a de valeur que partagée

MALAISE

### Re: [Plugin] Cyma Curve Tool

Thatnks TIG - again!

This will definitely be very handy for my ogee arches (which I would probably use more often than cymas)
0

Gaieus

### Re: [Plugin] Cyma Curve Tool

Here's an update viewtopic.php?p=230584#p230584

v1.4 20100311
Non-square forms now possible and sizes entered, X & Y.
VCB prompt now shows the chord-proportion value needed to get tangential ends - useful if it's a non-square form.
The arcs' segments can now be set.
'Gola' and 'Ogee' added to type descriptions.
Notes and lingvo files updated to match changes.
0
TIG

TIG
Global Moderator

Clipboard-1.jpg
0

dedmin

### Re: [Plugin] Cyma Curve Tool

I assume you refer to the 'broken curve' ?
It's down to how the arcs are drawn - I'll fix it
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Here's an update viewtopic.php?p=230584#p230584
v1.5 The 'broken' curve/arc glitch is fixed and the form is now a welded curve made from the two arcs...
0
TIG

TIG
Global Moderator

0

dedmin

Thanks TIG!
0

lapx

### Re: [Plugin] Cyma Curve Tool

i updated and now i get an error when starting su:
undefined method `deBabelizer' for main:Object

i'm on a mac
0
IOviz.com
SU Pro 2017 PC
Thea: latest
vray4SU latest

troyhome

### Re: [Plugin] Cyma Curve Tool

There is a file in the zip file called 'deBabelizer.rb' - this goes into the Plugins folder ???
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Three cheers! You've saved me loads of time, this is a much needed tool! My (paypal) check's in the mail!
0

youemailme

### Re: [Plugin] Cyma Curve Tool

Thank, I have it already [£]... watch out for some other tools that are in the pipeline...
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

TIG: Here's the Chinese lingvo file
0

hebeijianke

### Re: [Plugin] Cyma Curve Tool

Thanks. I'll add it to a future update - in the meanwhile any users wanting Chinese locale lingvo can extract this and put it into their ../Plugins/TIGtools/ folder...
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

I had used a different deBabelizer version instead of the one included with this plug, so simply replacing that with the one included... well, that fixed it! thanks
0
IOviz.com
SU Pro 2017 PC
Thea: latest
vray4SU latest

troyhome

### Re: [Plugin] Cyma Curve Tool

All current versions of deBabelizer.rb are identical so it shouldn't cause problems, as long as you have one - I distribute a copy of it with each tool that will use it in case you haven't already got a copy in Plugins...
It's the tool needed to translate the wording of prompts and dialogs etc to your 'locale' language, if there's a 'lingvo' file found to match it - most commonly these are EN-US [English - the base default], and FR[ench] and ES[panish], and sometimes ZH-CN [Chinese] or other 'locale' codes - but any 'locale' that's returned by the system is supported if you copy/rename a lingvo file and translate the phrases in it... If you are picky you could even 'translate' the base EN-US lingvo version so it says different things - e.g. 'colour' vs 'color' if you are not American but you have a EN-US locale - or even into 'Esperanto' phrases etc where that is not an official 'locale' !
0
TIG

TIG
Global Moderator

### Re: [Plugin] Cyma Curve Tool

Hi TIG - thanks for the great tool : I'm experiencing this glitch in 8 using 1.5 -
0

function

### Re: [Plugin] Cyma Curve Tool

I tested it with exactly the same dialog and Units settings and it works fine for me - the only difference is I have Vista rather than XP, but that shouldn't make any difference
At first I thought it might be because you had units displayed and accuracy set to no dp's - 4" versus 4.000 BUT that makes no difference to me either...
Can you get it to work with other permutations of settings or Units ?
0
TIG

TIG
Global Moderator