question about the transformation structure

Replies to This Discussion

Permalink Reply by David Rutten on June 23, 2012 at 10:43pm

Hi Wendong,

see attached. Hope it makes sense.

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David Rutten

david@mcneel.com

Poprad, Slovakia

Attachments:

• recursion.gh, 2 KB

Permalink Reply by David Rutten on June 23, 2012 at 10:44pm

Oh yes, you might want to put a test in there to make sure that minimumLength is never equal to or less than zero, otherwise you'll crash hard.

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David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Wendong Wang on June 23, 2012 at 11:09pm

Thanks for the file! It works, but I am still a bit puzzled by how you use Transform and Vector3d without declaring variables. It seems that they are the names for structures (according to RhinoCommon SDK), but you use them independently.

By the way, where can I get more information on basic concepts such as structure, constructor, operators, and other terms used in the RhinoCommon? I guess that the explanations of these concepts in the Grasshopper Primer are outdated? 

Permalink Reply by David Rutten on June 23, 2012 at 11:17pm

That is correct. The methods I call are Shared methods and they must therefore be called on the typename rather than any specific instance of that type.

Words like Class, Structure, Constructor, Operator etc. are not RhinoCommon specific. They are the same throughout .NET programming. Any introduction/reference that targets VB.NET should be sufficient to explain these concepts.

The Grasshopper primer is a little bit outdated, but when it comes to fundamental stuff like classes vs. structures, it will stay relevant for a very long time to come.

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David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Wendong Wang on June 23, 2012 at 11:21pm

Thanks for the info! 

Permalink Reply by David Rutten on June 24, 2012 at 6:55am

I wrote a blog post about Reference-Types vs. Value-Types. It's not really to my liking yet, I think it's still far more confusing than it could be, but maybe it will clarify a few things. I'll write another post soon that explains the different between Instance methods and Shared methods.

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David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Andy Payne on June 24, 2012 at 7:48am

Very well written post.  Thanks for sharing.

Permalink Reply by Wendong Wang on June 24, 2012 at 9:57am

Thanks for the post. The analogy you used at the end of the post makes things easier to understand. Look forward to your next post.