Line command

Can the options of ; perp, tang, vert, etc. be active after beginning the line command? Thanks for a great software.

Yes. I added some of the most useful to my middle mouse button pop-up.


Thanks DanBayn, I was hoping it would be something built into the line command after invoking it. Doesnt it make sense to choose options once a point of a line is picked?
I will use your example and thanks

When using the line command, after you type “line” and hit enter you can then manually type “end, cen, tan, etc…” and it will snap to only that option. Not sure if this is what you’re after.

Hi Ra_mull, I will give it a try. Thank you

Hi Mark - the command line options are for the first pick - Line > Perp only makes sense if you choose a curve to be Perp from and a point (the start of the line) on that curve - the line is then constrained to be perp to the curve. If you start Line and place a point, you’d need to start over and find a curve to be Perp from. If you want to be start a line and have it end perp to a curve, then the Perp OSnap is the tool…

Does that make sense?


Hi Mr. pascal, thanks for the reply. I guess I got that idea from R14 and 2D drawing. 3D is a different creature. What you explained makes sense.
For the sake of arguement, my mind says " pick your command" then its options . Line seems to fall in those parameters.
You do amazing work here at this forum . Have a great holiday season!

Hi Mr. Pascal again, On the same subject of “line”, I am only 3 years into Rhino and I will probably stick with it as I dont want to go through another learning curve of a different software.
I usually draw when possible in perspective view. I need lots of visible space to see things develop .Also stay with the defaut cplane most all the time. I dont do scripts much ( but need to). I use it pretty much as it comes out of the box.
Sub-d ,I am hoping develops into a great solid tool in Rhino.
A question on the curvature graph. Is it mostly used to see what curves are doing and to help modify them? Why is it on the surface tool bar?
This week I am just going to look into the pop- up toolbar and how to take advantage of it.
Again, thanks for all your hard work. Mark

Hi Mark - CurvatureGraph works on both curves and surfaces (displays on the surface isocurves). The graph shows the amount of curvature - the more curved, the taller the graph, so it is very useful to help understand how, for example, a curve ‘accelerates’ in curvature, where it might have flat spots or sudden bits of high curvature. You can use it to help adjust a curve to approach G3 continuity to another (no hard corner in the graphs of two curves where they meet - continuous rate of change of curvature) etc, Generally, designing ‘cool stuff’ one is after getting curves that are not only smooth but progressive in shape, with a visual logic that is in keeping with the design intent - the graph helps in analyzing some of the characteristics.

By way of an example- I like the lower curve better - the upper one has a slight increase in curvature on the left end, and tails off a little on the right end. The lower one has a continuous smooth acceleration in curvature - lowest at the left, and highest at the right end . The shape of both curves implies this type of organization but the upper one misses. Dunno if that helps…


Very helpful. I’ve always heard. Great curves make great surfaces. That is why I see curve graph being linked to the curve sidebar. I thank you .