Hi, I'm sure there's a good technical reason for this (maybe something to do with floating point accuracy), but it seems a bit strange to me. I was drawing up a plan of a room. I started by drawing a line, clicking the first point, typing 4400 (mm) and holding shift and snapping it vertically down. When I open the details box, it correctly states that the line is 4400mm long, but the x,y,z points don't agree with this (see screenshot). It is about 0.02mm out at the end (which is outside my tolerance of 0.01). I'm drawing close to the origin, so it's not like the coordinate values are extremely high.

I thought this wouldn't matter, but then I drew a line perpendicular off the bottom of the first line and began offset it up along side (to draw a staircase in plan). By the time I got to the top, the error had be magnified and was noticeably off at the top of the stairs. Could someone please explain this to me? 

Thank you!

Steven

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Hi Steven - I cannot reproduce this so far- it should be exact as far as I know... can you export the line and send it to me?

thanks,

-Pascal

pascal@mcneel.com

Hi Pascal, I've attached the line and the details pane as it appears here.

Thanks,

Steven

Attachments:

Hi Steven- thanks, it looks like the bug is in how Details ('What' command) is rounding the 'true' coordinates of the ends of the line- there is something sloppy there. Using EvaluatePt gives the expected coordinates (At the command line- the label, if on, does some rounding as well) , as does List on the line. 

thanks for pointing this out, we'll fix it...

-Pascal

pascal@mcneel.com

Hi Steven- you can, for now, get better, more consistent reporting from the What command (but not from Details until we fix this) by setting What to report units. (Start What with no selection and set the command line option) It will then pay attention to the display precision set in DocumentProperties > Units.

-Pascal

pascal@mcneel.com

Thanks Pascal! I'm glad i'm not just going crazy!

Steven

This fix also seems to improve the repeatability of Analyze/Length when using object snaps.

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