Rhino 6 documentation bugs


(Kelvin Cheng) #153

RH-13288 is fixed in 6.11 to preview mesh wireframe in all display modes except Rendered and Raytraced.


Please mention this fact in documentation. What do you think about replacing “the mesh settings” with “render mesh settings” in documentation?

(Kelvin Cheng) #155

I will.

(Kelvin Cheng) #156


How about now?
…documentproperties/mesh.htm had some information out of date. It said render meshes are not editable. The fact is they can be edited/modified by Displacement, Edge Softening, Shutlining or Thickness in object properties.



These edits look perfect to me. (You write better documentation than I do.) Don’t forget to include RH-13288 fix in the documentation when Rino 6.11 is released.


Accurate modeling documentation is here: http://docs.mcneel.com.s3.amazonaws.com/rhino/6/help/en-us/user_interface/accurate_modeling.htm?tocpath=Quick%20Tour|Accurate%20modeling|_____0

I would mention absolute tolerance in this document because rookie Rhino users do not understand how important it is.

Lots of info about tolerances is here: https://wiki.mcneel.com/rhino/faqtolerances

It says: Use a tolerance setting equal to or one order of magnitude tighter than (1/10 of) the best tolerance you can hold through your manufacturing process – or one order of magnitude tighter than your smallest modeled detail, whichever is smaller.

This is good rule for 3D printed objects. The tolerances can be relaxed for objects having dimension entities - if it looks good, it is good. Swedish firm Arcam makes electron beam machines which print variety of strong alloys with +/– 0.4 mm accuracy. Other metal/alloy printing machines have lower accuracy. Parts made of polymers (plastics) are elastic, so 0.5% accuracy is generally enough to ensure that they fit. If you design all fitting parts, give them extra space - better to make the fit too loose than too tight. Typical mold shrinkage of polymers is 2% - the polymers shrink when they solidify. Shapeways service business 3D prints polymers with about 0.2% accuracy. It 3D prints steel with 5% accuracy. It casts silver with about 2.5% accuracy.

The same document mentions Command-line calculator, but it does not mention its default angle unit. The default angle unit is radian.

The most common mistakes of rookie Rhino users:

  1. Boolean operations fail because absolute tolerance is too big.

  2. Boolean operations or fillets fail because one edge of NURBS surface has been shrunk to a point, called singularity. Sometimes singularity cannot be avoided. For example, the apex of a cone is always a singularity. If fillets fail, trim away bad parts of the fillets and blend the good parts. (The only way to eliminate this problem is replacing NURBS with better geometric modeling kernel.)

  3. Renditions, zebra stripes, and environment maps look jagged because render meshes have low density.

Old info about failing fillets is here: https://wiki.mcneel.com/rhino/advancedfilleting


Basic info about solid objects is in this document: http://docs.mcneel.com.s3.amazonaws.com/rhino/6/help/en-us/seealso/sak_solid.htm?tocpath=Quick%20Tour|Solids|_____0

I would mention the fact that Rhino cannot make models of simple, real-world objects having enclosed voids. For example, Rhino cannot make a model of a tennis ball because tennis ball encloses empty space filled with air. Rhino solids (except non-manifold solids) cannot enclose voids because Rhino is a surface program rather than solid program (like Solidworks, PTC Creo, Catia, Siemens NX, and Solid Edge).


And you know this statistically how? You teach Rhino to “rookies”?

Boolean operations failing is a common complaint, both for rookies and experienced users alike. In general it is not

but rather because Rhino cannot find a complete intersection between the objects, caused by overlaps, open edges, etc… https://wiki.mcneel.com/rhino/booleanfaq

I would also say that one of the most common causes of the above for beginners and intermediate level people is a lack of understanding of how Boolean operations actually work and how to do the operations they involve manually.


No and no. You have much more experience than I do, so your opinion in this matter is much more reliable. (Unlike most people, I welcome criticism.)

(Kelvin Cheng) #161

Why do you think radian is the default angle unit? Can you provide an example that shows radian is the default angle?


Copy any line from 0 to 0,tan(pi/4) or to 0,tan(0.785398163397448). Measure (vertical) distance between the lines. The distance is exactly 1, which means that the tan function used radians.

By the way, the command-line calculator chapter is duplicated here: https://docs.mcneel.com/rhino/6/help/en-us/user_interface/command-line_calculator.htm


“When prompted for any angle value, append any angle unit name makes sense any of the languages Rhino supports”.

Point to copy to: 0,tan(45d) --> copies 1mm in Y…

(Kelvin Cheng) #164

Everything this topic talks about is absolutely accurate. What you enter for distance or angle constraints is what you get. For examples, when Absolute tolerance is 0.1, you are able to create a line with a length of 0.001. When Angle tolerance is 1.0, you are able to rotate an object with 0.01 degree. They are not affected by tolerance settings.

I added a link in the Units topic to open https://wiki.mcneel.com/rhino/faqtolerances.

“Rhino is a surface modeler. It’s not possible to subtract a sphere inside another sphere to create a tennis ball-like object that has a solid wall enclosing a void.”

I added this note to the BooleanDifference command topic.

I think users use tan know what it is.


Yes, they know that value returned by the tan function depends on the units used by the tan function. If tan(0.785398163397448) returns 1, it means that its angular input is measured in radians. If tan(0.785398163397448) returns 0.013708642534394, it means that its angular input is measured in degrees.


Rhino documentation file ( https://docs.mcneel.com/rhino/6/help/en-us/seealso/sak_extrude.htm ) confuses SelExtrusion command with SelID command twice:

Select object by its object ID number.
The SelExtrusion command will not select polysurface or surface objects. Use this command if you want to see which objects are extrusion objects.

Select object by its object ID number.

(Kelvin Cheng) #167

Fixed, thanks.


RemoveMultiKnot command link in: https://docs.mcneel.com/rhino/6/help/en-us/commandlist/command_list.htm
points to diferent command: https://docs.mcneel.com/rhino/6/help/en-us/commands/insertcontrolpoint.htm#InsertKnot

(Kelvin Cheng) #169

Fixed. Now it opens https://docs.mcneel.com/rhino/6/help/en-us/commands/insertcontrolpoint.htm#RemoveMultiKnot



Guides (guide lines) are visible in perspective views at some view angles and invisible at other angles. It seems to be a bug, but Pascal Golay believes that this bug probably cannot be fixed, so it is a limitation, rather than a bug. If it is a limitation, it would be good idea to mention it in documentation. more info is here: Rhino 6.10 - Guide display bug

Another AddGuide bug: Undo does not undo/remove AddGuide.

TiltView documentation file is posted here: https://docs.mcneel.com/rhino/6/help/en-us/commands/tiltview.htm

It says: The view rotation snaps in five-degree increments. The keyboard shortcut, Shift + Alt + Right mouse button displays an “s” to indicate the snap mode is on.

In reality, Rhino displays digit 5 rather than letter s. Windows 10 cannot take a screenshot of this digit, but I looked at it through magnifying glass and I have seen digit 5 with great clarity.


ambiguous documentation:

(Kelvin Cheng) #172

I added a note about this in https://docs.mcneel.com/rhino/6/help/en-us/commands/addguide.htm
“Guides may not always display in perspective views when the view is rotated.”

Are we going to have undo working for smart points too? I think that’s too much for smart points and guides.

Corrected in the paragraph and the illustration.