Projection of arbitrary rotated circle on planeCenter of circle on a stereographic projectioncalculate out-of-plane and in-plane rotation from virtual camera position.Calculating rotated relative positions on 2D planeCalculating angle on ellipseGet the camera transformation matrix (Camera pose, not view matrix)Width of rotated planeComputing the properties of the 3D-projection of an ellipse.Section of cone through the rotated plane (with and without offset)What is equation of moved and rotated ellipse, parabola and hyperbola in XY plane?what is the equation of a rotated ellipsoid?

Print last inputted byte

Recursively updating the MLE as new observations stream in

Exit shell with shortcut (not typing exit) that closes session properly

Determine voltage drop over 10G resistors with cheap multimeter

Writing in a Christian voice

When did hardware antialiasing start being available?

Help with identifying unique aircraft over NE Pennsylvania

Why didn’t Eve recognize the little cockroach as a living organism?

Did Nintendo change its mind about 68000 SNES?

Why doesn't the fusion process of the sun speed up?

Does convergence of polynomials imply that of its coefficients?

Is this Pascal's Matrix?

Friend wants my recommendation but I don't want to

How do researchers send unsolicited emails asking for feedback on their works?

Pre-Employment Background Check With Consent For Future Checks

Gauss brackets with double vertical lines

What is the difference between something being completely legal and being completely decriminalized?

Hackerrank All Women's Codesprint 2019: Name the Product

Is xar preinstalled on macOS?

Is there any common country to visit for uk and schengen visa?

"Marked down as someone wanting to sell shares." What does that mean?

DisplayForm problem with pi in FractionBox

What is it called when someone votes for an option that's not their first choice?

Why is indicated airspeed rather than ground speed used during the takeoff roll?



Projection of arbitrary rotated circle on plane


Center of circle on a stereographic projectioncalculate out-of-plane and in-plane rotation from virtual camera position.Calculating rotated relative positions on 2D planeCalculating angle on ellipseGet the camera transformation matrix (Camera pose, not view matrix)Width of rotated planeComputing the properties of the 3D-projection of an ellipse.Section of cone through the rotated plane (with and without offset)What is equation of moved and rotated ellipse, parabola and hyperbola in XY plane?what is the equation of a rotated ellipsoid?













0












$begingroup$


I have a camera that is trying to work out the angle that a disc is rotated at.



Assuming this was an orthographic projection, how would I work out the angle that the circle is at from the ellipse that I can see?



The circle will have some 3D rotation applied to it and then it will be projected on to the plane that is the camera.



Below is an example of such a transform:



enter image description here










share|cite|improve this question









$endgroup$
















    0












    $begingroup$


    I have a camera that is trying to work out the angle that a disc is rotated at.



    Assuming this was an orthographic projection, how would I work out the angle that the circle is at from the ellipse that I can see?



    The circle will have some 3D rotation applied to it and then it will be projected on to the plane that is the camera.



    Below is an example of such a transform:



    enter image description here










    share|cite|improve this question









    $endgroup$














      0












      0








      0





      $begingroup$


      I have a camera that is trying to work out the angle that a disc is rotated at.



      Assuming this was an orthographic projection, how would I work out the angle that the circle is at from the ellipse that I can see?



      The circle will have some 3D rotation applied to it and then it will be projected on to the plane that is the camera.



      Below is an example of such a transform:



      enter image description here










      share|cite|improve this question









      $endgroup$




      I have a camera that is trying to work out the angle that a disc is rotated at.



      Assuming this was an orthographic projection, how would I work out the angle that the circle is at from the ellipse that I can see?



      The circle will have some 3D rotation applied to it and then it will be projected on to the plane that is the camera.



      Below is an example of such a transform:



      enter image description here







      geometry rotations






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Oct 20 '15 at 10:49









      MorgothMorgoth

      1088




      1088




















          1 Answer
          1






          active

          oldest

          votes


















          0












          $begingroup$

          Orthogonal projection has the property that a line segment which is parallel to the plane of projection gets mapped onto a segment of the same length. All other segments will become shorter. The more so the farther they are from being parallel.



          So the original diameter of the circle corresponds to the length of the major axis of the ellipse. Along that axis, the angle between original and projected segment is zero. Perpendicular to that is the minor axis of the ellipse. There the angle between original and projection is maximal, i.e. equal to the angle between original and projected plane.



          Imagine cutting the scene along a plane which is perpendicular to the plane of projection, and passes through the minor axis. The projection there appears as a right triangle: one leg is the direction of the projection, one leg is the projected segment (i.e. the minor axis of the ellipse) and the hypothenuse is the original diameter of the circle (i.e. the major axis of the ellipse). Do you know how to work out the angles of a right triangle if you know the hypothenuse and one of the legs?






          share|cite|improve this answer









          $endgroup$












            Your Answer





            StackExchange.ifUsing("editor", function ()
            return StackExchange.using("mathjaxEditing", function ()
            StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
            StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
            );
            );
            , "mathjax-editing");

            StackExchange.ready(function()
            var channelOptions =
            tags: "".split(" "),
            id: "69"
            ;
            initTagRenderer("".split(" "), "".split(" "), channelOptions);

            StackExchange.using("externalEditor", function()
            // Have to fire editor after snippets, if snippets enabled
            if (StackExchange.settings.snippets.snippetsEnabled)
            StackExchange.using("snippets", function()
            createEditor();
            );

            else
            createEditor();

            );

            function createEditor()
            StackExchange.prepareEditor(
            heartbeatType: 'answer',
            autoActivateHeartbeat: false,
            convertImagesToLinks: true,
            noModals: true,
            showLowRepImageUploadWarning: true,
            reputationToPostImages: 10,
            bindNavPrevention: true,
            postfix: "",
            imageUploader:
            brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
            contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
            allowUrls: true
            ,
            noCode: true, onDemand: true,
            discardSelector: ".discard-answer"
            ,immediatelyShowMarkdownHelp:true
            );



            );













            draft saved

            draft discarded


















            StackExchange.ready(
            function ()
            StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f1488959%2fprojection-of-arbitrary-rotated-circle-on-plane%23new-answer', 'question_page');

            );

            Post as a guest















            Required, but never shown

























            1 Answer
            1






            active

            oldest

            votes








            1 Answer
            1






            active

            oldest

            votes









            active

            oldest

            votes






            active

            oldest

            votes









            0












            $begingroup$

            Orthogonal projection has the property that a line segment which is parallel to the plane of projection gets mapped onto a segment of the same length. All other segments will become shorter. The more so the farther they are from being parallel.



            So the original diameter of the circle corresponds to the length of the major axis of the ellipse. Along that axis, the angle between original and projected segment is zero. Perpendicular to that is the minor axis of the ellipse. There the angle between original and projection is maximal, i.e. equal to the angle between original and projected plane.



            Imagine cutting the scene along a plane which is perpendicular to the plane of projection, and passes through the minor axis. The projection there appears as a right triangle: one leg is the direction of the projection, one leg is the projected segment (i.e. the minor axis of the ellipse) and the hypothenuse is the original diameter of the circle (i.e. the major axis of the ellipse). Do you know how to work out the angles of a right triangle if you know the hypothenuse and one of the legs?






            share|cite|improve this answer









            $endgroup$

















              0












              $begingroup$

              Orthogonal projection has the property that a line segment which is parallel to the plane of projection gets mapped onto a segment of the same length. All other segments will become shorter. The more so the farther they are from being parallel.



              So the original diameter of the circle corresponds to the length of the major axis of the ellipse. Along that axis, the angle between original and projected segment is zero. Perpendicular to that is the minor axis of the ellipse. There the angle between original and projection is maximal, i.e. equal to the angle between original and projected plane.



              Imagine cutting the scene along a plane which is perpendicular to the plane of projection, and passes through the minor axis. The projection there appears as a right triangle: one leg is the direction of the projection, one leg is the projected segment (i.e. the minor axis of the ellipse) and the hypothenuse is the original diameter of the circle (i.e. the major axis of the ellipse). Do you know how to work out the angles of a right triangle if you know the hypothenuse and one of the legs?






              share|cite|improve this answer









              $endgroup$















                0












                0








                0





                $begingroup$

                Orthogonal projection has the property that a line segment which is parallel to the plane of projection gets mapped onto a segment of the same length. All other segments will become shorter. The more so the farther they are from being parallel.



                So the original diameter of the circle corresponds to the length of the major axis of the ellipse. Along that axis, the angle between original and projected segment is zero. Perpendicular to that is the minor axis of the ellipse. There the angle between original and projection is maximal, i.e. equal to the angle between original and projected plane.



                Imagine cutting the scene along a plane which is perpendicular to the plane of projection, and passes through the minor axis. The projection there appears as a right triangle: one leg is the direction of the projection, one leg is the projected segment (i.e. the minor axis of the ellipse) and the hypothenuse is the original diameter of the circle (i.e. the major axis of the ellipse). Do you know how to work out the angles of a right triangle if you know the hypothenuse and one of the legs?






                share|cite|improve this answer









                $endgroup$



                Orthogonal projection has the property that a line segment which is parallel to the plane of projection gets mapped onto a segment of the same length. All other segments will become shorter. The more so the farther they are from being parallel.



                So the original diameter of the circle corresponds to the length of the major axis of the ellipse. Along that axis, the angle between original and projected segment is zero. Perpendicular to that is the minor axis of the ellipse. There the angle between original and projection is maximal, i.e. equal to the angle between original and projected plane.



                Imagine cutting the scene along a plane which is perpendicular to the plane of projection, and passes through the minor axis. The projection there appears as a right triangle: one leg is the direction of the projection, one leg is the projected segment (i.e. the minor axis of the ellipse) and the hypothenuse is the original diameter of the circle (i.e. the major axis of the ellipse). Do you know how to work out the angles of a right triangle if you know the hypothenuse and one of the legs?







                share|cite|improve this answer












                share|cite|improve this answer



                share|cite|improve this answer










                answered Oct 20 '15 at 12:45









                MvGMvG

                31k450105




                31k450105



























                    draft saved

                    draft discarded
















































                    Thanks for contributing an answer to Mathematics Stack Exchange!


                    • Please be sure to answer the question. Provide details and share your research!

                    But avoid


                    • Asking for help, clarification, or responding to other answers.

                    • Making statements based on opinion; back them up with references or personal experience.

                    Use MathJax to format equations. MathJax reference.


                    To learn more, see our tips on writing great answers.




                    draft saved


                    draft discarded














                    StackExchange.ready(
                    function ()
                    StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f1488959%2fprojection-of-arbitrary-rotated-circle-on-plane%23new-answer', 'question_page');

                    );

                    Post as a guest















                    Required, but never shown





















































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown

































                    Required, but never shown














                    Required, but never shown












                    Required, but never shown







                    Required, but never shown







                    Popular posts from this blog

                    Lowndes Grove History Architecture References Navigation menu32°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661132°48′6″N 79°57′58″W / 32.80167°N 79.96611°W / 32.80167; -79.9661178002500"National Register Information System"Historic houses of South Carolina"Lowndes Grove""+32° 48' 6.00", −79° 57' 58.00""Lowndes Grove, Charleston County (260 St. Margaret St., Charleston)""Lowndes Grove"The Charleston ExpositionIt Happened in South Carolina"Lowndes Grove (House), Saint Margaret Street & Sixth Avenue, Charleston, Charleston County, SC(Photographs)"Plantations of the Carolina Low Countrye

                    random experiment with two different functions on unit interval Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern)Random variable and probability space notionsRandom Walk with EdgesFinding functions where the increase over a random interval is Poisson distributedNumber of days until dayCan an observed event in fact be of zero probability?Unit random processmodels of coins and uniform distributionHow to get the number of successes given $n$ trials , probability $P$ and a random variable $X$Absorbing Markov chain in a computer. Is “almost every” turned into always convergence in computer executions?Stopped random walk is not uniformly integrable

                    How should I support this large drywall patch? Planned maintenance scheduled April 23, 2019 at 00:00UTC (8:00pm US/Eastern) Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?How do I cover large gaps in drywall?How do I keep drywall around a patch from crumbling?Can I glue a second layer of drywall?How to patch long strip on drywall?Large drywall patch: how to avoid bulging seams?Drywall Mesh Patch vs. Bulge? To remove or not to remove?How to fix this drywall job?Prep drywall before backsplashWhat's the best way to fix this horrible drywall patch job?Drywall patching using 3M Patch Plus Primer