Current code files for Steampunk Jacket are here: http://www.sew-brilliant.org/wiki/index.php?title=Men’s_Steampunk_Jacket_1870-1900
Once the pattern is generated with the extension steampunk_jacket.inx and steampunk_jacket.py:

1.select all points that aren’t corners and set to auto-smooth.  Set points at the waist line and elbows to symmetrical.
2. set Inkscape Preferences/Steps to 56.25px (5/8″) for Outset to equal a standard seam allowance.
3.select the pattern outline
4.copy then paste in place
5.select Path/Outset
6. select original pattern outline
7. click on Edit Object’s icon on upper toolbar, set stroke-style to be a dashed line.

These steps will be incorporated into the extension soon, but I’ve got a deadline of this Friday to sew this up, and the pattern’s not completed yet.
Here’s the result:

VintageSewing.info is an extraordinary resource for those who don’t want to invest any $$ to pick up some of these techniques.  At the very least it can fire your imagination to do your own creation:

How to Draft Basic Patterns, 3rd ed.1985 by E. Kopp, V. Rolfo, B. Zelin, L. Gross – still had the plastic neckline curve template in the front cover inside pocket! Sweet…

Designing Apparel Through the Flat Pattern, rev. 5th ed., E. Kopp, V. Rolfo, B. Zelin, L. Gross

The Complete Guide to Practical Cutting (1853), 2nd ed. by Edward Minister & Son

“Standard” Work on Cutting (Men’s Garments) 1886, reprint 1990, by Jno. J. Mitchell Co.

The Blue Book of Men’s Tailoring: Grand Edition of Supreme System for Producing Men’s Garments (1907), by Frederick T. Croonberg

I’ll try to post the file on the wiki soon.  These two pieces had to be generated from the same file, as they shared several reference lines.  I need to create patterns for the sleeve, both pockets, the collar, collar facing, and lapel facing.  As you can see, next step is to select points on a path and change them to ‘smooth’ or ‘symetrical’, add ‘label’ to the path attributes, and a long list of other things.  But first, this jacket. My son is 6’1″, chest 38″, waist 32″, and the pattern is based on a person who is 5’9″, chest=38″, waist=34″.  So this picture’s proportions won’t match the pictures in the book.

My stepson wants something to wear to DragonCon.  That’s a fairly tight delivery date. So last night I wrote the inkscape extension to create thejacket back pattern.  This weekend I’ll finish the front jacket pattern.  Then the muslin test, then the real fabric.  Maybe I’ll have time for the trousers.  Maybe not…

This picture and the old method to make this suite are from ‘Men’s Garments 1830-1900‘ by R. I. Davis

I rewrote the programs again, tweaking the curves and re-thinking the algorithm.

The latest files are posted at Current Code Files

I’ve been acting like a big old very scary goat, and I’ve probably been pretty smelly too.  But on the bright side I’ve developed the process to draw the front bodice block pattern.  To make these block patterns, there’s usually paper folding involved, and hand drawing of curves.  It’s taken me a while to keep folding and re-folding the paper until the mathematical relationships become apparent.  The processes I’m posting are using averages for shoulder slopes and bust cup sizes and other things, so these are the basis of what will be refined in the future.  Still, they should fit pretty well.  I may have something ready next week.

Here’s the link to the process flow: http://www.sew-brilliant.org/wiki/index.php?title=Bodice_Front

The Back Bodice Block Pattern is done. Must remove reference lines, pretty it up and give it a nice bouncy shine. Commented code as I went along because I remember nothing from day to day. Three months ago I had never written any  object oriented code, and never used illustration software. Now I’ve hit this milestone – the Back Bodice pattern block.  I will try to post the files on the wiki tonight while catching up on Xena, maybe a re-viewing of ZardOz. All the guys are out of the house.  It’s just me and the sherbert (uh, sorbet?) between now and Sunday afternoon. I honor and revere my slack.  It’s the source of my super powers.

The link to the .inx and .py files can be found on my wiki page Current Code Files

Oh yeah.  I had a shoulder line with a slope.  Needed to make a  dart perpendicular to shoulder line at the midpoint. Aha!  Get slope of shoulder line, negate & invert to get perpendicular slope.  Use midpoint as center point of circle. Solve line and circle equations simultaneously.   My issues were that python doesn’t like ^ for exponents, likes ** instead.  Use as many parentheses as you can possibly stand, didn’t get the right results with  r / (1+m**2)**(1/2) .   This was changed to (r/((1+m**2)**(.5))) and it worked perfectly.  And did you notice my Quadratic Bezier Curve?

I’ve been struggling with creating bezier curves in an Inkscape SVG drawing from within a custom Inkscape extension written in Python.  It turns out that it’s the formatting of the element call that was the problem.  Here’s what worked for me – This is a simple example. I’ve included only one control point between the two end points.  The first coord (x1,y1) in mypathattribs is the begin point and is designated by M to move the pen to that point, the last coord (x2,y2) is the end point and doesn’t require a designated label, and the control point in the middle (c1,c2) is designated by Q.
My wordpress template isn’t allowing me to have specific line indents, so if you cut and paste you’ll need to add indents for the lines within DrawQCurve.

def DrawQCurve(self,my_layer,x1,y1,x2,y2,c1,c2,mycolor):
mypathstyle   = {'stroke': mycolor,  'stroke-width': '15px',  'fill': 'none'}
mypathattribs = {'d': 'M '+str(x1)+', '+str(y1)+'  Q '+str(c1)+', '+str(c2)+'  '+str(x2)+', '+str(y2), 'style': simplestyle.formatStyle(mypathstyle)}
inkex.etree.SubElement(my_layer, inkex.addNS('path','svg'), mypathattribs)

Converting the numbers to string and storing them in variables and putting the variables in the mypathattribs didn’t work, although this method works with other SubElement calls.  Placing the style information after the path definition was required as well, again this is different than with other SubElement calls. For some reason, I had to specify that the stroke-width was in pixels.  I received error messages when ‘stroke-width’:’15′ was in mypathstyle, but didn’t for ‘stroke-width’:’15px’ .  And again, this is different than with other SubElement calls. And appending ‘in’ for inches in the coordinate strings didn’t work even though it works for other calls, so I multiplied by 90 (90px per inch is default in Inkscape) to convert inches to pixels- I left this out because it wasn’t necessary for the example.

Woot!

Couldn’t help it, ordered a few more books, found a couple at a thrift store:

Applied Geometry for Computer Graphics and CAD – (Springer Undergraduate Mathematics Series) by Duncan Marsh

Men’s Garments 1830-1900: A Guide to Pattern Cutting and Tailoring by R. I. Davis

Professional Patternmaking for Designers: Women’s Wear and Men’s Casual Wear by Helen Joseph Armstrong

Patternmaking for Fashion Design by Jack Handford

MILLINERY Book Hat Making 4 Books-in-1 25 Lessons 1928 by The Fashion Institute

Millinery Book Hat Making Make Hats Design 1925 by Jane Loewen

The New Encyclopedia of Modern Sewing, 1946 ed. Frances Blondin

The previous great SVG learning site that I blogged about earlier was out of date in 2009.  The current version is at the W3 site.  It’s been there for some time. And it’s still the best I’ve found.

Here’s the current SVG Primer: http://www.w3.org/Graphics/SVG/IG/resources/svgprimer.html

It appears that SVG is a bit like Erector sets.  It’s actually pretty simple, but with SVG/Python/Inkscape so many people have done so many complicated things with it, that it ain’t easy to peel back the layers to learn how to start building from scratch.

It’s hard to find source data that reveals the foundational information on building SVG in a way that doesn’t follow the  ‘example 1, example 2, that’s enough info you don’t need to know where the extra information in those examples came from or why they were necessary to make this work’ formula.

This blog is a journal about my experience in learning to program. And about my experience in creating open source fashion design software using Python, SVG and Inkscape.  Exciting for the world, eh?  I’m trying to document how through lots of work I can find tiny a bit of basic info here and a tiny bit elsewhere.  It’s slow. Very very slow.

Yeah, it’s official. I’ve created a template for patterns which is based on pixels.  The units for creating or editing an object within an extension can be changed to inches or centimeters by appending ‘in’, ‘cm’ or ‘px’ to the measurement specified in the create element call. This doesn’t change the base unit of the document, will just need a global var in first extension or put a database lookup in each extention to specify the client’s measurement choice.  This actually makes it easier to make changes per client. Metric is preferable because smaller units  results in greater accuracy — but it’s tough for me in the US to find sewing notions in centimeters so I’m fairly stuck with inches. But the program will allow for both so that clients can use the measurement they prefer.

Found a great site which seems very promising in explaining how to control the results of the path command. An SVG Primer for Today’s Browsers by David Daily.

http://srufaculty.sru.edu/david.dailey/cs427/StateOfArt-Dailey.html

Okay, it seems that this is from 2009.  It’s now available and up-to-date at the W3 site http://www.w3.org/Graphics/SVG/IG/resources/svgprimer.html

My main wiki page has been ravaged and sacked.