Possible error in the documentation of RotateText command

Download0091 shared this question 5 years ago
Answered

Hello,


The documentation for the RotateText command found at http://www.geogebra.org/wiki/en/RotateText_Command states


The text is rotated around the top left corner (also known as corner 4) of the box containing the text.


It seems that the text is not rotated around the top left corner (corner 4) but the bottom left corner (corner 1). The attached worksheet shows the angle of rotation relative to corner 1.


John.


https://ggbm.at/2363503

Comments (4)

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Hello Noel,


I am not sure what to say.... I think the sample I uploaded makes it quite obvious that the rotation is taking place around corner 1. The angle specified in the RotateText command matches the angle measured from corner 1 not corner 4.


John.

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I tried your suggestion which you can see in the attached worksheet. Doing the rotation you suggested makes it even clearer that the text is not rotating about Corner 4. Corner 4 is perpendicular to the axis of rotation, it isn't even on the axis of rotation.


This can readily be seen when the rotation is 180 degrees. If the rotation were happening about Corner 4, at 180 degrees the text would be vertical instead of horizontal (look at the angle at Corner 4 when the angle is 180 degrees.)


https://ggbm.at/2364147

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Have a good day too Noel :-)

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Hello,


Depending upon how one chooses to measure the angle of rotation, it is not incorrect to state that the rotation takes place about Corner 4 as the documentation does. That said, it is also correct, not to mention consistent with the way angles are usually measured, to state that the rotation takes place about Corner 1 which is the point of origin of the text.


The attached worksheet shows how the rotation point can be considered to take place about Corner 4 or Corner 1.


John.


https://ggbm.at/2364883

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