Transition from oval to round?

Alan Fraser

Transitioning from a true oval (not a lozenge) to a circle couldn't be easier. Simply draw a circle, extrude it, then scale to top face in one direction while holding down Ctrl.

Gaieus

Ah yes, Alan, but according to the image in the first post, it's indeed a lozenge... (Otherwise Fredoscale could be used to "scale" it to a lozenge, too)

Alan Fraser

Yes, I noticed that. I also noticed that it's a negative shape...unlike your's, mine or anybody else's examples.
Not that that would make any difference if you were merely going to stitch the nodes together.

Gaieus

Well, often simply stitching is the fastest and easiest way actually.

Dave R

One more way. No plugins needed.

circ toloz.png

Draw a circle. Drag radius out on axis.
Rotate circle so edges are on axis. If you use a default 24-sided circle, rotate the circle 7.5 degrees.
Use Push/Pull to create cylinder.
Select top edge, right click, choose Explode Curve.
Use a left to right selection box to select half of circle*.
Use Move tool to move the selection the required distance.
Repeat for the other side.

It's not really half of the circle. It's half minus the two edges that will be the long edges of the lozenge.

Jean Lemire

Hi folks.

See this SU file for ideas.

Circle to rounded rectangle transition.skp

derei

@tig said:

What was originally show isn't an 'oval', it's a 'lozenge' - a rectangle with rounded ends.
This means that the suggested method of scaling a circular top of a cylinder into an 'oval' [ellipse] won't work.

The lozenge has at least two extra segments around its perimeter compared to the simple circle [4 as drawn!], that is assuming that the two semi-circular ends have the same number of segments as half of the full-circle.

Sorry for off-topic, as I'm not a native english speaker, I'm always interested in learning.

I always thought that "lozenge" is something else, and Wikipedia says the same http://en.wikipedia.org/wiki/Lozenge

Also, there seems to be a slight difference between oval and ellipse as they show it here http://en.wikipedia.org/wiki/Oval

So, what's the name of this shape formed by two half of circle joined by segments?
Thanks

TIG

An ellipse is a geometrical figure - a circle is a special case of an ellipse, where both axes are the same length.
An oval is a more general term meaning 'egg-shaped'; so it could refer to an ellipse OR to a non-elliptical egg form.
A lozenge can indeed be a 'diamond-shape' - this comes from 'heraldry' [many rhomboid shapes with two axes of symmetry [that are not 'oblongs'] can be thought of as 'lozenges']... but today most English speakers will hear the word 'lozenge' and think of something that is a rectangular shape with rounded [rather than pointed] ends - like a throat-lozenge candy/sweet made that shape so it is easier to suck/swallow - this kind of 'lozenge' usually has two ends that are are semi-circular, although four rounded corners can also make a 'lozenge-like' shape... See here http://www.google.co.uk/search?q=lozenge+shape&hl=en&prmd=imvns&source=lnms&tbm=isch&ei=dy89T4idC8Sg8QOgxLmnCA&sa=X&oi=mode_link&ct=mode&cd=2&ved=0CBEQ_AUoAQ&biw=1440&bih=779#hl=en&tbm=isch&sa=1&q=lozenge+shaped&pbx=1&oq=lozenge+shaped&aq=f&aqi=&aql=&gs_sm=3&gs_upl=6128l6128l0l6339l1l1l0l0l0l0l0l0ll0l0&bav=on.2,or.r_gc.r_pw.r_qf.,cf.osb&fp=d35ae3f6e2e6993b&biw=1440&bih=779

derei

@ TIG
Thank you very much! I always cherished your help and explanations.

mitcorb

I am glad that TIG was able to help you.

Gaieus

This is what our beloved SU (pro) companion, LayOut draws as a lozenge.