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Working with primitives in Patterns - Daniel Goerner - 2012-05-25

I admit, I don't have any clue how primitives work.
Chris suggested that I should change some circles made of triangles with primitives in one of my patterns.

So I tried that. The first thing that confused me is that I can't adjust the width of rings. A ring with the radius of 1 is too big, 2 ist too small.

Then, how can I assure that the primitives don't overlap? I can't select the vertices to see their position, so I don't know if the ring I put in another ring has the right size.

Then I finally got the first primitives in the right position (a circle, a ring and a squarecirclethingy around it) connected these with triangles with the rest of the pattern and checked that with edger2. The pattern looks right, the primitives look right. Just the connection between both: unmatched edges around the squarecirclethingy. How do i avoid that?

Seriously, I hate primitives as much as condlines.


Re: Working with primitives in Patterns - Tim Gould - 2012-05-25

Hi Daniel,

Could you maybe show the part you're working on? Would make it easier to help by example.

TIm


Re: Working with primitives in Patterns - Daniel Goerner - 2012-05-25

See attached lpc file.

[Edit] I also attached the exported dat.


Re: Working with primitives in Patterns - Willy Tschager - 2012-05-26

Daniel Görner Wrote:The first thing that confused me is that I can't adjust the width of rings. A ring with the radius of 1 is too big, 2 ist too small.

I guess I know what you're asking for. Use the rotation matrix do stretch rings. Check out the code in:

[dat_part 973pwa]

and examine how I authored the buttons using a black 4-4ring3.dat.

w.


Re: Working with primitives in Patterns - Chris Dee - 2012-05-26

I assume this is in response to my comments here and here.


Re: Working with primitives in Patterns - Chris Dee - 2012-05-26

Daniel Görner Wrote:The first thing that confused me is that I can't adjust the width of rings. A ring with the radius of 1 is too big, 2 ist too small.

The numeric suffix in the filename (4-4ringN) indicates the inner radius of the ring - the outer radius is always 1LDu greater. For example the 4-4ring4 primitive creates a ring with an inner radius of 4LDu and an outer radius of 5LDu. But you can scale the primitive with the matrix, so scaling 4-4ring4 by 0.25 would give a ring with an inner radius of 1LDu and an outer radius of 1.25 LDu.

The Rings and Cones utility written by Niels Karsdorp at http://www.philohome.com/isecalc/rings.htm is useful for calculating how do do this.


Re: Working with primitives in Patterns - Daniel Goerner - 2012-05-27

Can we cut that for now and go directly to question 3? The unmatched edges?


Re: Working with primitives in Patterns - Chris Dee - 2012-05-27

If for the "squarecirclethingy" you mean the 4-4ndisc primitive, then its edges should perfectly match a ring or disc primitive centred on the same point.


Re: Working with primitives in Patterns - Daniel Goerner - 2012-05-27

Oh, it does. What I mean is that the surrounding triangles dont match. See my attached file above.


Re: Working with primitives in Patterns - Chris Dee - 2012-05-27

Sorry - I don't understand what you are asking. To avoid T-junctions when building around a 4-4ndis you need only treat the corners and mid-points of the sides as vertices. Could you post a file just showing this problem?