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Beyond the Basics Duplicating complex shapes to create inside lines
  1. #1
    LostLibrarian LostLibrarian @LostLibrarian

    I'm not sure if I'm phrasing this correctly, but here goes.

    I purchased a pattern that was supposed to be used to cut a laser project, but the lines cut the piece into the individual shape pieces rather than a single shape with the interiors of each individual piece cut away. (ill1)

    I fooled around with duplicating sections and reducing them to create the interior lines. (ill2)

    But those were the easy ones, and now I've got many more complex shapes I'd like to duplicate and reduce, but those shapes are grouped in a way that I can't make and reduce a copy (ill3)

    Following the guidance I've seen in other places, I tried using the Path > Effects > Offset and found that didn't work either. I've also tried using both the Linked and Dynamic Offset with no luck.

    Is what I'm looking to do possible? Is there a way to do it more simply than trying to edit the nodes? Should I give up and start looking for other patterns?

    Thanks for any help anyone can give. 

     

     

     

    Ill3
    Ill2
    Ill1
  2. #2
    COD COD @COD
    *

    Can you use the Shape Builder tool  in 1.4.2 to recreate the profiles? If not, another possibility is the Paint Bucket tool. From there, maybe offset will work.

    Attach the SVG and I am sure a few others will make great suggestions. 
     

    Edit: Usually on something like this, once I get the profiles cleaned up; I will do a path>combine.  Then set the stroke to 1mm (or more). Then path>flatten. I will end up with 2 objects. Delete the top object. 

    Edit 2: With the supplied PNG (that was chopped). Because it was chopped, wasn't able to recreate the surrounding scroll pattern. Red is what is cut out. 
     

  3. #3
    LostLibrarian LostLibrarian @LostLibrarian

    Here's the SVG. Thanks for the tips - I'll try working with them and see what happens. With my skill it'll probably turn into an aerial photo of Brooklyn. 🙄

    Design 8
  4. #4
    COD COD @COD
    *

    Ok - I was going to tell you to simply to:
    Path>Combine
    Stoke = 1 mm
    Set fill color to red (so path>flatten will work correctly)
    path>flatten
    delete the top object

    That does work, however, I noticed some issues with it that would require some node editing. Yuck!
     



    Since I hate node editing - I may try use the Paint Bucket tool with a 1mm stroke. 

     

  5. #5
    COD COD @COD
    *

    You still have to add your bridging (otherwise the center "gonna" fall out 🤣). Be best to redesign that scroll. Maybe 4  pieces rotated around the center. 
    Good video on scroll patterns (2 parts): https://youtu.be/ZMzysbUAXw8?si=imEjasFM1QIoPtI4
    Really, I tried the shape builder method, tried my method (flatten) and it seems the best method was the paint bucket tool. 

  6. #6
    David248 David248 @David248
    *

    I'm not sure what you are looking for : you want to achieve this ? Here, paths have a style "oultine mode like" : no fill, thin black stroke. One path for the center rosace, a two additional paths for outer leaves. 

    • Rosace was done, except for ring by setting an appropriate stroke width* (remember it), then doing path > stroke to path and path > union. Let's call the result inner rosace.
    • Then ring was duplicated and selected with inner rosace and I did path > intersection, to trim inner rosace to ring. 
    • I duplicated one more time the ring and applied it an offset LPE** with a minus stroke width* Offset, I flattened the LPE (path > object to path) then reversed path direction (path > reverse).***
    • I selected original ring and it's insetted copy and did path > combine. Then selected it with inner rosace and did path > union
    • Outer parts where done with the path > stroke to path method. 

     

    ** I did an inner offset to avoid thinning the space between rosace and outer parts. 

    *** When combining two circles with same path orientation, the visual result isn't the one expected (except if you change fill rule, another discussion). To get the right visual aspect, paths need to have a different path orientation. 

  7. #7
    David248 David248 @David248
    *

    Once cut : it should look like these three parts, if you dont add bridges 

  8. #8
    COD COD @COD

    The geometry is complete in the original SVG. I am also assuming it is the red fill (negative space cut) is what is to be laser cut out. 

    To me , the easiest way is just to set the stroke to 1mm (or more for a rigid design) and do a path>flatten. May have to do some node editing afterwards to eliminate such paths like this. I got lazy and simply did a quick and dirty Bucket Fill. 

     

  9. #9
    Tyler Durden Tyler Durden @TylerDurden

    Looks like a seasonal ornament or window hanger.  I might go this way:

  10. #10
    COD COD @COD
    *

    Tyler: Oh - That worked great for the Fusion 360. Only had to select a single profile!  

    Edit: Tyler had to combine two nodes of the circle that were sitting on top of each other using the node editor. If you don't do that, you will end up with a deformation when you do a stroke to path. 

  11. #11
    COD COD @COD

    Tyler - you just solved an unrelated issue I have had for the past 18 months. I guess I really need to learn and understand booleans better. 

  12. #12
    Tyler Durden Tyler Durden @TylerDurden

    Even after removing the extra node, the file was wonky when I tried to use the shape builder tool, so I used the stock booleans to get the result. 🤷

  13. #13
    COD COD @COD

    Yeah - I noticed that when I attempted using Shape Builder on the OP's original SVG. Sort of disappointed in that. I use Shape Builder quite a bit as "training wheels" because my lack of experience with booleans. 

    There is a bug report on this: https://gitlab.com/inkscape/inkscape/-/issues/4477

    Something about not being able to detect interior regions correctly. If you will notice in this example - the dark profile does not work. Either you can't select it or it automatically gets merged with other profiles. 

     

     

  14. #14
    COD COD @COD

     

  15. #15
    Tyler Durden Tyler Durden @TylerDurden

    Yeah, that's frustrating.

     

    @ LostLibrarian, we should note that The artwork could also be used to engrave the interior details and only cut the outer features.

  16. #16
    LostLibrarian LostLibrarian @LostLibrarian

    Thank you all for your suggestions. Tyler, I'm following your instructions even though I don't understand the reasoning behind some of them 😁, although COD did tell me why the circle nodes had to be edited. Just out of curiosity, are there any visual hints of extra nodes that I can look for on other files that I need to convert? 

    I'm glad this answered other people's questions as well, but I really appreciate the time and effort you gave to me. Cheers!

  17. #17
    COD COD @COD

    There is a new extension in 1.4. Extension>Modify Path> Clean Up Path . Really saves me a ton of time trying to find those tiny boogers! 
    Not 100% certain if it would have cleaned up that extra node in that circle. The instruction says "END NODES". 

    I use these settings just for particular use. Haven't played with the other settings.

     



    With your question, Tyler not only solved your problem but led me to clues on solving an issue that has drove me insane for a year are more. 
    TIP: I suggest saving his videos! I do all the time as reference. 

  18. #18
    LostLibrarian LostLibrarian @LostLibrarian

    That was the very first thing I did. I can practically follow it with my eyes closed! Although I still don't know why he does some things, but I'm trying to simplify my life and follow his simple instructions. Understanding will come with time and practice, I tells myself.

  19. #19
    Aero Aero @Aero◻️
    *

    I would expect some issues in Inkscape when using 1 inch per user unit in document properties.

    A higher drawing precision like 1:100 converts stroke to path without any node editing up front. Press the small dot after Scale: before typing in the new value.
     

    Document Properties Precision
  20. #20
    COD COD @COD

     I have problems wrapping my head around booleans that is why I started using the Shape Builder tool. Now, with the issues with it - guess who is going to have to learn booleans? 🤣

  21. #21
    Lazur Lazur @Lazur

    Side note. The original file is too small and has a bit extreme scale factor. Changing that to 1 will decrease some of the wonkyness. 

    Combining paths and converting stroke to path "should" work -do the necessary editing before the converting. You have less nodes to adjust.

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