Default direction for rotate, gumball rotate, etc

It seems like most if not all rotation in rhino defaults to counterclockwise. In top view, entering 90 in _rotate or the gumball rotation handle both create a 90 degree counterclockwise rotation. Grasshopper is similar.

This seems very counterintuitive to me. Is there a reason it’s done this way?

Hello - that is pretty much standard - the circle ‘starts’ at 3 o’clock, 90 is at 12, etc.



If your career path had required you to take all the pure math/scientific math courses that the geeks who wrote all the Rhino routines did you’d think the way Rhino does it was the usual way. Coming from a different background does make it seem unnatural. It’s possible for us ordinary people to get used to it though, just like driving on the left side of the road in England.



So, basically the same reason grasshopper components’ angle inputs default to radians.

It’s just a convention. The x axis being the first axis, this is the starting point. The first quadrant is the positive X and Y, the second is then -X, Y etc. This makes a counter clockwise movement.

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I think this is because Grasshopper is programming based on 3D math after all. So internally it has to work with radians. If we feed it degrees the component will have to change back to radians for further calculation. So it makes sense then to keep radians as default. I have to admit though that I mostly change a component’s angle input to degrees for convenience.

Right, if we’re actually trying to build something, we use degrees.

And if I was to create a shapediver that gives a consumer audience the ability to rotate something, I’d stick a negative before the input I set at “degrees”.

Seems like there should be options in Grasshopper and Rhino to choose mathy or lay language as the default.