Skip navigation
Currently Being Moderated

Ellipse inside a circle with no overlapping paths?

Jul 25, 2012 6:05 PM

Tags: #circle #subscribe #ellipse #tangent #snap_to #non_tangent #astute_graphics

I'm trying to draw a circle and an ellipse so that the ellipse shares exactly two points of contact between the two paths (not centered).

 

This is seemingly impossible with the tools provided since, if you draw an ellipse normally, with the anchor points of the ellipse on the circlular path, there are four points of contact, which means the two paths overlap.

 

I've tried revolving a line segment that goes from the edge of the circle to the middle of the circle (not center) with similar results.

 

Drawing the ellipse first doesn't help either.

 

Astute Graphics has a plug-in, Subscribe that would almost work, except it only draws circles, not ellipses.

 

Am I overlooking someting extremely obvious, or am I correct to say that illustrator can't do this? I'm using CS5. Maybe this is something that is fixed in CS6 with a snap to path option?

https://sphotos-a.xx.fbcdn.net/hphotos-ash4/376190_10151056719927332_39329461_n.jpg

 
Replies
  • Currently Being Moderated
    Jul 25, 2012 7:42 PM   in reply to Fobioid

    From theView Meenu turn off the Snap to Grid and Snap to Point. Now try it.

     

    Screen Shot 2012-07-25 at 10.38.40 PM.png

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 25, 2012 8:32 PM   in reply to Fobioid

    You say it is impossible and I had no problem so either it is a question of skill or some other unknown factor effecting your install of Illustrator.

     

    Perhaps it is a conflict with a plug in. Look for yourself.

     

     

    Screen Shot 2012-07-25 at 11.25.07 PM.png

     

    Screen Shot 2012-07-25 at 11.25.52 PM.png

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 25, 2012 8:56 PM   in reply to Fobioid

    In the example I posted your were correct but if you turn off smart guides as well and go into outline mode you can align it properly notice the I have the sahpe builder tool active on the upper segment between the outer circle and inner ellipse. I hope this is helpful.

     

    Screen Shot 2012-07-25 at 11.53.15 PM.png

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 25, 2012 9:09 PM   in reply to Fobioid

    Is this what you are trying to achieve? Can't be done just by using the Ellipse tool while creating an ellipse but after that it is relatively easy if you use the Smart Guides to transform and snap it. The zoomed in details at the snapping points are shown at the maximum zoom level in Outlined view.

    Untitled-1.gif

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 25, 2012 9:37 PM   in reply to Fobioid

    Do you have align to pixel grid truned on anywhere?

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 25, 2012 9:48 PM   in reply to Fobioid

    You have to hold the Ctrl button on your keyboard when dragging an object with the selection tools in order to show the snapping labels on all parts of a path.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 25, 2012 10:08 PM   in reply to Wade_Zimmerman

    It just takes a little work sometimes you get it quickly and some times it is an effort the last time I did it I was slightly shy of the measuremet and simply use the width input field in the control panel to slowly increase the size by very small amounts until I achieved the goal. It's not automatic!

     

    Screen Shot 2012-07-26 at 1.06.57 AM.png

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 25, 2012 10:43 PM   in reply to Fobioid

    I am glad to see you are able to accomplish what you have to accomplish.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 26, 2012 8:34 AM   in reply to Fobioid

    john wyffels wrote:

     

    This is what it looks like when I try to do it. ...

    I guess you are looking for maximum precision
    Then try the following, I haven't tried it myself but on theory it should work. First, to mark the snapping point on the ellipse, with the Line Tool, create a short line that crosses the ellipse and send the line to back (Ctrl + [ ). Select the ellipse and the circle, copy them (Ctrl + C), hide them (Ctrl +3), and paste the copies in front (Ctrl + F). Select the ellipse and with the Direct Selection Tool drag from the point of intersection with the short line and drop  on the path of the circle where it snaps and you see no overlap at maximum zoom. Now use the Shape Builder tool the way you did in your video but do not scale the little segment that remains. If the segment contains 2 edges, delete the edge formed from the ellipse and keep the edge formed from the circle. With this remaining edge selected, choose Object > Path > Add Anchor Points and this will add an anchor point in the middle of the edge. You can delete the anchor points at the ends and keep the one in the middle. Apply Show All (Alt+Ctrl+3). Now drag the ellipse from the intersection point with the short line and drop it on the anchor point you just made.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 26, 2012 8:56 AM   in reply to Fobioid

    Just to make sure is this box checked or not in your AI preferences?

     

    Screen shot 2012-07-26 at 8.54.56 AM.png

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 26, 2012 9:11 AM   in reply to Fobioid

    I just tried several times what I suggested  in my previous post doing it at maximum zoom but I can't get on overlap as you showed on your video. On a couple of tries I got a short single edge and on one try I managed to get a single point. I guess within the precision limits of Illustrator and depending on the shape and position of the paths the overlap could be a short edge instead of a point. How about sharing your file with the shapes you are trying? Just put a short line intersecting the ellipse at the point you want to snap and share the file so, we can try.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 26, 2012 9:34 AM   in reply to emil emil

    You misunderstood my post ou accomplishe what you wanted to but don't realize it.

     

    Thee is  a time when yoiu have gone far enough.

     

    You are making artwork there is nothing in this world that needs more percsion than what you were able to accomplish.

     

    It's art work. If you continue on your quest eventually you get do to the molecular level and that will make it obvious how unrealistic the quest for perfection is, you can acomplish what you need to do at the level of percissio you need so let it go at that.

     

    Even in Rocket science theere are tolerance factors. There are mathematical equations we know are true but we cannot resolve but it still works for us when doing percsion work like pi.

     

    It's artwork you have it, move on you do not have a need to be more percise.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 26, 2012 9:39 AM   in reply to Fobioid

    John,

     

    Presuming you wish to (be able to) do it with an arbitrary set of one circle and one smaller ellipse and using the Illy tools, this may be done with patience.

     

    You may nudge it (to the best possible fit), with Smart Guides on, and using the symmetry:

     

    1) Create the circle and the ellipse,

    2) Align them horizontally to centre and vertically to the top,

    3) Drag the ellipse vertically down to close fit,

    4) Zoom all the way in on either target area,

     

    You may repeat some of the following steps,

     

    5) Use the Up/Down arrow to get closer,

    6) Hover over the area of near contact so both spines show,

     

    When you are really close, go back and forth between the following, using one hand for each task:

     

    7) Either

    7a) Object>Transform>Move and set the vertical move to (decreasing values down to) 0.001 or 0.0001, after the first move, use Ctrl/Cmd+D to repeat, or

    7b) Edit>Preferences>General>Keyboard Increment to the same value,

     

    8) Move the cursor along the ellipse and see what Smart Guides say: if they just say path the ellipse is too low, if it says intersect more than once the ellipse is too high and you can see the length of the overlap, if it says intersect once you are there.

     

    In 7) and 8) you may end up having to decide between two intersections with a small overlap or a tiny gap between the paths.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 27, 2012 2:35 AM   in reply to Fobioid

    Thank you for sharing your solution, John.

     

    Being a bit slow in the upgrade (if not something else), I had never even heard of the Small Gap.

     

    And for my part you are welcome.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 27, 2012 8:39 AM   in reply to Jacob Bugge

    If the OP had pointed out what it was they were trying to accomplish we might have been able to point him in the right direction but he only gave us half the of the problem.

     

    They should have mention what they want to accomplish was to use the shape builder tool to make two shapes and not leave even a very, very, very, small gap. True they showed us that using the shape builder tool shoed that it was not in contact but they never mentioned they want to make two new shapes using the shape builder tool.

     

    I am not certain how the shape builder tool accomplishes what it does but I would think it has to alter the geometry in order to resolve such a problem of course it is so small an alteration that it is virtually non existent. As was the overlap.

     

    But for Jacob to see here is the optons for the shape builder tool.

     

    Screen Shot 2012-07-27 at 11.27.31 AM.png

     

    Screen Shot 2012-07-27 at 11.27.43 AM.png

     

    So these are how the shape builder tool can work and clearly they have these options realizing this is artwork and the level of percission is simply not that great.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 27, 2012 9:15 AM   in reply to Wade_Zimmerman

    Wade_Zimmerman wrote:

     

    If the OP had pointed out what it was they were trying to accomplish we might have been able to point him in the right direction...

    Yeah, I thought that with the video demonstration, the OP wanted to make a point that Illustrator is not very precise, and I didn't realize at all that the goal is to avoid the small segments when using the Shape builder tool.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 27, 2012 11:17 AM   in reply to emil emil

    When I grab the path, it will snap to that point on the path which I am holding it, but not the point in which it will only bring it to the circle without overlapping it.

     

    same here, I was following this and I thought the request was to make the ellipse to snap to the circle anywhere they touched.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 27, 2012 2:06 PM   in reply to Fobioid

    Thank you for sharing, Wade. Quite impressive.

     

    Wade, Emil, Carlos, I believe that John had higher hopes than you, including a truly accurate alignment even in a difficult case like this, thereby avoiding approximation and cheatery, sorry new smart features.

     
    |
    Mark as:
  • Currently Being Moderated
    Jul 27, 2012 2:55 PM   in reply to Jacob Bugge

    It does matter what his high hopes were he did not obtain! it is still an approximation. He might be under the impression that the smal gap thing some how fixes the geomery but i say it alters the original path to fit a certain criteria, in other words an approximation.

     

    But I agree wwith you he was trying to avoid facing the facts that he was not going to achieve this task.

     
    |
    Mark as:
  • Currently Being Moderated
    Aug 1, 2012 10:11 AM   in reply to Fobioid

    Hi John

    Here is how I made it. Providing you can start with a line at 90 degrees to the artboard it is possible to use the align tool. I just tested with pathfinders divide - and the result was no small segments

     

    no_overlap.png

     
    |
    Mark as:

More Like This

  • Retrieving data ...

Bookmarked By (0)

Answers + Points = Status

  • 10 points awarded for Correct Answers
  • 5 points awarded for Helpful Answers
  • 10,000+ points
  • 1,001-10,000 points
  • 501-1,000 points
  • 5-500 points