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  1. #1
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    Question Construct an Ellipse from it Focal Points and Height

    To understand this Challenge, you need to be aware of http://www.xara.com/templates/: the triangle made between the centre, the minor axis (top) apex and a focal point has its longest side the same length as from the centre to a major axis (side) apex.

    Given a focal length and a height of both 400px, re-construct the ellipse.

    Click image for larger version. 

Name:	Ellipse.png 
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ID:	122810

    Acorn
    Acorn - My currently active Xara software: occasionally serviced XDPX, purposely unserviced XDPX12 & XDPX11 (32/64-bit), unserviced XWD Premium 15 & 12, XPGD10, X3D7 and lots of 'permanently-owned' licences back through time (to CC's Artworks)

  2. #2
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    Default Re: Construct an Ellipse from it Focal Points and Height

    I'll wait a bit...

  3. #3
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    Default Re: Construct an Ellipse from it Focal Points and Height

    I can feel the tension building.

    Acorn
    Acorn - My currently active Xara software: occasionally serviced XDPX, purposely unserviced XDPX12 & XDPX11 (32/64-bit), unserviced XWD Premium 15 & 12, XPGD10, X3D7 and lots of 'permanently-owned' licences back through time (to CC's Artworks)

  4. #4
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    Default Re: Construct an Ellipse from it Focal Points and Height

    Quote Originally Posted by Acorn View Post
    I can feel the tension building.

    Acorn
    ok, here is mine...

    Click image for larger version. 

Name:	ellipse_FPH.png 
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ID:	122822

    Of course you can use the same triangle. You rotate it first then create the circle and than stretch it horizontally while pressing the SHIFT key to get the ellipse.
    Last edited by Marco D; 05 December 2018 at 05:19 PM.

  5. #5
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    Info Re: Construct an Ellipse from it Focal Points and Height

    Quote Originally Posted by Marco D View Post
    ok, here is mine...

    Click image for larger version. 

Name:	ellipse_FPH.png 
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ID:	122822
    Marco, i like the elegance of your solution. Thank you.
    There is no need to delete the Node, just use the square and rotate it 45 around the circle's centre.

    I used the square's diagonal to become the circle's radius right off.
    I just then Shift-flattened the circle into the height of the square.

    Click image for larger version. 

Name:	Ellipse construction.png 
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    Both solutions will work for any focal length and minor axis.

    Acorn
    Acorn - My currently active Xara software: occasionally serviced XDPX, purposely unserviced XDPX12 & XDPX11 (32/64-bit), unserviced XWD Premium 15 & 12, XPGD10, X3D7 and lots of 'permanently-owned' licences back through time (to CC's Artworks)

  6. #6
    Join Date
    Nov 2018
    Location
    Italy
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    Default Re: Construct an Ellipse from it Focal Points and Height

    Yes, of course, I made it triangular because of the image you posted.
    As you said there is no need to cancel the node.
    But your solution is even faster.
    Marco.

 

 

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