# Software suitable for drawing knots **URL:** \ **Category:** Factual Questions\ **Created:** [June 20, 2007, 10:26am UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699 "2007-06-20T10:26:41Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 20, 2007, 10:26am UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/1 "2007-06-20T10:26:41Z")
I’m looking for a program that will make it easier for me to draw knots - at the moment, I’m doing it in Powerpoint (yes, I know), and it’s a real PITA because it isn’t possible to have part of an object lay over the top of another part of the same object (at least not in the sense I need). [Here](http://www.gurman.co.uk/stuff/knot.png) is a picture of a typical knot - I had to draw this one as follows: -Draw the knot with a thick black line -Copy it, thin it down, make it red and place it over the black line (makes a red line with black edges) -Draw in the edges of crossings by hand - otherwise it looks like [this](http://www.gurman.co.uk/stuff/knot2.png) - and it’s completely ambiguous as to which thread is laying over the top of which. With a simple knot like this one, drawing in the six edges of the crossings isn’t a big deal, but I want to draw some configurations that are very much more complex (the reader won’t have to work it all out from a single picture - it will be step-by-step, but I want the program to manage the crossings for me without me having to worry about manually maintaining the Z order) So… is there a graphics program out there that can make this all a bit simpler for me? ---
**Author:** ![si\_blakely](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@si\_blakely](https://boards.straightdope.com/u/si_blakely)\ **Post date:** [June 20, 2007, 11:08am UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/2 "2007-06-20T11:08:56Z")
[QUOTE=Mangetout] I’m looking for a program that will make it easier for me to draw knots - at the moment, I’m doing it in Powerpoint (yes, I know), and it’s a real PITA because it isn’t possible to have part of an object lay over the top of another part of the same object (at least not in the sense I need). [Here](http://www.gurman.co.uk/stuff/knot.png) is a picture of a typical knot - I had to draw this one as follows: -Draw the knot with a thick black line -Copy it, thin it down, make it red and place it over the black line (makes a red line with black edges) -Draw in the edges of crossings by hand - otherwise it looks like [this](http://www.gurman.co.uk/stuff/knot2.png) - and it’s completely ambiguous as to which thread is laying over the top of which. With a simple knot like this one, drawing in the six edges of the crossings isn’t a big deal, but I want to draw some configurations that are very much more complex (the reader won’t have to work it all out from a single picture - it will be step-by-step, but I want the program to manage the crossings for me without me having to worry about manually maintaining the Z order) So… is there a graphics program out there that can make this all a bit simpler for me? [/QUOTE] MS Visio can do this (guessing you have Office installed) - just with a heavy bezier line style and a shadow. Or assemble it out of bits (linked at the end points) and use the Z-Order to get it all correct. I did the same with Xara Xtreme on Linux, too. Si ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 20, 2007, 12:17pm UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/3 "2007-06-20T12:17:24Z")
Thanks for that - I’m going to install Xara Xtreme now and try it. I wonder if Inkscape will do what I want… ---
**Author:** ![stolichnaya](https://avatars.discourse-cdn.com/v4/letter/s/bcef8e/32.png) [@stolichnaya](https://boards.straightdope.com/u/stolichnaya)\ **Post date:** [June 20, 2007, 12:25pm UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/4 "2007-06-20T12:25:44Z")
Everything that I know will require you to split the “rope” into elements. But you can still simplify things - if I had to do this I’d probably draw the knot with intersections and then slice the shape at the appropriate points to create the proper overlap. I would use Illustrator and the knife tool for this. 3D is an excellent option but I am none too skilled with it and knots seem like a difficult problem to solve, and I would guess that the output wouldn’t be as attractive. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 20, 2007, 12:53pm UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/5 "2007-06-20T12:53:38Z")
Xara Xtreme looks promising so far, but -How do I set the colour of a shadow? -How do I join objects? - If I group them, I can’t access the handles to adjust their curves, also, I’d have to do the alignment of the butt ends manually this way. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 20, 2007, 12:54pm UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/6 "2007-06-20T12:54:39Z")
Also… The shadow tool wants to cast a shadow at the ends of the bezier lines, which is going to show the joins… ---
**Author:** ![cantara](https://avatars.discourse-cdn.com/v4/letter/c/6f9a4e/32.png) [@cantara](https://boards.straightdope.com/u/cantara)\ **Post date:** [June 20, 2007, 3:14pm UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/7 "2007-06-20T15:14:06Z")
[This site](http://www.fieggen.com/shoelace/index.htm) has a lot of really good pictures and animation. I seem to recall him detailing what he had used to draw them, but I can’t seem to find it now. Maybe he’s removed it. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [June 21, 2007, 12:30am UTC](https://boards.straightdope.com/t/software-suitable-for-drawing-knots/408699/8 "2007-06-21T00:30:38Z")
Thanks for that, **cantara** - I’ve seen that site before but it completely slipped my mind. I contacted the author, who replied with some very useful info: > [@](#): > > **Ian Fieggen wrote:** > … > > I used Adobe Illustrator for the majority of the drawing, as this allows > nice smooth curves. However, the “depth” is due to shadowing, which was not > so easy to achieve in Illustrator. The diagrams were therefore imported into > Photoshop, where the shadows were added manually. > > The most difficult process with doing the diagrams comes when one string > passes both over and under another string, as it does with even the most > simple overhand knot. Each element of a diagram can be above or below > another element, but not both! To go over and then under, I therefore do one > of two things: > > My original method involved creating two versions of the image, one with the > yellow portions on top of the blue portions, the other with the blue on top > of the yellow. Paste both versions of the image on top of each other into > Photoshop as two separate layers. Then use the eraser to rub out any > interesctions that are incorrect (eg. blue over yellow), revealing the > correct intersection on the other layer below (eg. yellow over blue). > > Another method is to use the “Pathfinder” tool in Illustrator to chop one > path where it overlaps another path and should be underneath. With the path > chopped at the point where it intersects, the result looks like it is > actually running underneath. > > On some of my diagrams, this is LOTS of work because the lines are actually > comprised of a coloured line with a black outline. I end up with one layer > comprised of all the underlying black, with the yellow, blue and grey > segments all lying on top, each neatly cut to their exact shape. > > Anyway, that’s how I’m currently producing my diagrams. You may instead > choose to look at a free program called “KnotPlot”, which is full 3-D knot > drawing software. I found out about this too late because it would mean that > I’d have to re-do all my existing diagrams as well, but for you, it may be > perfect. > > Anyway, I hope that’s enough info to get you started! > > Have a great day, > > Ian Fieggen 😉 The double-layer idea is a great one, knotplot looks really good as well.