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Hi I'm trying to figure out how to calculate the coordinates of a dot at a certain percentage point on an arc. Let's say the dot starts at (800, 300), the half-way points is (400, 0) and the end point is (0, 300). Let's say I want to calculate where the dot will be after traveling 25% of the arc. I'm really clueless where to start on this, thanks for your help.

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    Is this an arc of a circle?2012-09-29
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    Well its shape would fit the edge of a circle, but how big that circle would be I have no idea. Imagine the sun rises at (800, 300), the highest point it reaches is (400, 0), and it sets at (0, 300). How would I calculate its coordinates when it's risen 50% (half-way between (800, 300) and (400, 0))2012-09-29
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    There are infinitely many parabolic arcs that go through those three points. Do you have any more information about the function for the arc?2012-09-29
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    Oh yes I see now >_<. Stupid me, well I will just make a giant circle and chop the top off and use that as my arc then. I can calculate that then since I know the radius, thanks lol. :)2012-09-29

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