Cplane Origin offset

[davidcockey]

https://wiki.mcneel.com/rhino/farfromorigin

How accurate is Rhino?

@Matt3

Does it matter what the modeling units are (in Settings)?

Yes it matters. Rhino stores geometry in the units used for modeling. Change the units in Options > Units > Model units, select the rescale option, and the numbers used to calculations and storage for the geometry change. Calculations and storage use coordinates in the world coordinate system, not in local Cplane systems.

@Matt3

Will the display get corrupted, especially in render mode?

Possibly. Display problems caused by too far from the origin are a recurring topic in posts here… Display calculations in the GPU use lower precision than geometry calculations in the CPU.

Bug? Rhino isn't accurate far from origin

I expect that many graphic cards will use single precision for rendering. That means that even though your render mesh may be defined in double precision, it will still look jagged on screen.

Wish: far from origin

Single precision were used in meshes early on. And graphics cards use single precision natively. But in Rhino, it has more to do with using doubles. Double has 15 decimal digits of precision. Some operations like square root cannit return completely accurate results within 15 digits, so you end up with rounding. Which makes the 15 digits less reliable, say half of them. So we use tolerance to handle that. And this is where the trouble begins. Set tolerance down to 0.001 inches for NURBS calcul…

@Matt3

Will booleans have any additional trouble?

That depends on the size of the details in the geometry.