Creating 3rd point of a triangle from 2 points with 2 measurements

cath — 2017-01-15T11:51:36-05:00 — #1

Hello everybody,

I'm a recent user of PatternMaker and MacroGen and I don't understand everything at this point !

I have an issue and can't find how to solve it.

I have to place a point, let's say point T, distant from point R according to a certain measurement (distance from chest to shoulder), AND from point P according to another measurement (shoulder length).

By hand, I'd make two arcs from points R and P with my compass, and the point T would be at the intersection of the 2 arcs.

One solution is perhaps to create the 2 arcs with MacroGen and then use the 2 arcs intersect function, but it seems to me a little complicate.

Is it possible to use code or a logic function for this work ?

Have a good day !

Catherine

eugenienaber — 2017-01-17T09:37:03-05:00 — #2

Catherine,
you are exactly right.
you only get that point through an intersection of two arcs. This means adding 3 points for every arc .
You have to make two times a quarter of a circle and which quarter you want is important for your points (upper left, upper right, down left or down right). For instance the upper right quarter circle:
point 1 x=0, y=measure
point 2 x=measure, y=0
point 3 (curvepoint0 x=measure, y=measure
The intersection point has to be at the inside of the curves. It can not be outside the curve.
If you are not quite sure which quarter you should make it is also possible to rotate the quarter 45 degrees for having a better intersection. When you want i can give you the values of the points for that.

I have added on the wishlist for MG already a new point command where automatically the 3 points for a quarter of an circle are added. I am using the quarter of a circle arcs a lot of times in my macros.

greetings
Eugenie

cath — 2017-01-17T11:46:05-05:00 — #3

Hello Eugenie,

Thank you for your efficient reply.
That's what I thought.
I'm gonna try your method, if I succeed in drafting it ! I'll post the result.

Great thanks.

Catherine

cath — 2017-01-17T12:18:51-05:00 — #4

Hello again Eugenie,

It works!
I've verified with the compass in PatternMaker testing the macro and the distance of point T is perfect.
Thank you very much, I had had the same idea of drafting a quarter of a circle, but I did not understand how to place the arc corner.

Regards

Catherine