Thread: Math Problem

  1. #1
    Registered User
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    Math Problem

    Hi all,

    I have a little problem.

    Say I have a image at x=100 y=100.
    When I press 't' the image moves around in a circle with radius 20 (the circle is invisible)

    So this image moves around the circumference of the circle in a clockwise direction.
    When I click T again it stops and move back in a anticlockwise direction.

    Any help with the maths behind this would be much appreciated.

    Thanks

  2. #2
    Ethernal Noob
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    read about the sin and cos functions. They are able to plot points given their radius on a unit circle. With some simple multiplication you can plot it at any multiple of that unit circle.

  3. #3
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    ahh yes that seems to be the way forward. Much appreciated

  4. #4
    Ethernal Noob
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    you also need to convert the degrees to radians

  5. #5
    Frequently Quite Prolix dwks's Avatar
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    That's only if you actually want to use the sin() and cos() functions in the C standard math library. If you just want to understand the concept of how the images rotates in a circle, you don't need to.

    And if you use sin() and cos(), you'd likely need to go the other way as well.
    dwk

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