-1.#IND00 - rotate by amount problem

[Tiles]

And again i am beaten by MMF floats calculations. I need floats. But this time i cannot find a workaround.

What i want to do is to rotate given points by a given amount. Green dot is center. Yellow dot my sourcedot. Bluedot is the dot i want to set to yellow dot plus 90 degrees. I need distance and angle of yellow dot for that. Distance works. I have the distance. But fail at the angle because the calculation fails.

The calculation for the angle is: ACos(Y( "dot" )/value( "distance" )) . A simple calculation. But all i get as a result is -1.#IND00 instead a useful value most of the times.



I need a working angle. With floats because i need it as precise as possible. Any ideas?

[Werbad]

Use an extension to retrieve the angle. If you use aCos/aTan/aSin you have to add extra checks since they only return values from -90 to 90, or even invalid values like in your example.

[Tiles]

Thanks for the tip. Any clue which extension and how to achieve? I tried Advanced Math, Advanced Direction Object, and Direction Calculator so far. Without success.

[Benicle]

Advanced Direction object has direction between two points doesn't it?

[DanielRehn]

Indeed it does, I think the expressions looks like this...

Direction("Advanced Direction Object", X1, Y1, X2, Y2)

[Tiles]

I need the angle, oh wait, you mean i get the angle back here? Trying ... indeed. Thanks

Now i just need to get it to work ...

[Werbad]

Note that the Directions work reversed from angles. Use:
Direction("Advanced Direction Object", X1, Y2, X2, Y1)
to retrieve a correct angle.

[Tiles]

I get mad with this. The advanced direction object works. And this example sets at least the blue dot in the same distance. Unfortunately it doesn't care about the new angle. It sets itself at the sourcepoint, using the old angle. And i cannot find out why. Could somebody please point me to the error here?

[Tiles]

Ah, that's indeed it. I have to reverse as you told me. Then it works. Many thanks

But it still has a mayor flaw. The angle is not correct. This is definitely not 90 degrees:

[SEELE]

hmm try.. ATAN2((y2-y1)/(x2-x1))