Body block generation based on body measurements

Hi all, I’m new to seamly and actually I was searching for software that would translate my measurements into basic body blocks. I’m currently learning pattern drafting from a pro and I use the Books of Aldrich, but I find those methods very primitive and based on far too few body measurements and too many guidelines that often “fit” but and then require alterations afterwards.

I’m looking for first time right pattern drafting and that is theoretically possible. With all the measurements that I input in seamly 2D, it should be able to reproduce my body in 3D and produce tight fitting body blocks ready for me to built upon when I start designing tailored clothes.

Is this the ultimate ambition of Seamly2D? Does anybody know about open source or affordable software that does this properly (as in using as many body measurements as possible instead of only the default set)


Hello & welcome to Seamly!

Yes, if I don’t misunderstand you, that is the goal of the Seamly project. I have personally used it to produce an uncomfortably form-fitting pull-over shirt of quilting cotton. The only adjustment I needed to make was fixing the neck hole to be big enough for more than just my neck, (oops!) That’s with very little pattern drafting experience, but a coat-hangar physique. I did not use an established system, just what I’ve picked up from here & there.

If you know a programmer familiar with Blender’s back end, & interested in a project, I’m confident that @slspencer would be grateful for the referral. Meanwhile some people have managed to get patterns exported to Blender, I don’t know if any of them are active these days.

I hope that answers your question, if not, say the word; someone else will be by who may understand your needs better.



Most pattern drafting systems are designed to produce a “proportional” pattern based on an “ideal” body shape. Some systems also then allow you to apply “direct” measurements to further fit a pattern to the measurements.

If you want clothes to fit your body you should be draping on a dress form molded from your body, rather than trying to draft a pattern. Drafting will never attain a perfect fit - that’s what fittings are for. Again most systems are designed to produce a silhouette if you will, and not to create an exact 3D model. BTW… tailoring is a construction process, not a fit. When someone says this is a tailored jacket, it means certain construction methods were used VS just sewing it together. Part of the tailoring process is manipulating the fabric - such as steam shrinking or stretching fabric - so as to effect a better fit. For ex: I could choose to take the same jacket pattern, and either tailor it, or just sew it together. The tailored jacket should look & wear better, and will most likely look more period correct. In other words it’s the tailoring that makes for a better fitting garment not drafting an exact pattern. And to be honest… a big part of tailoring is to create the understructure (like canvases and shoulder pads) to create a silhouette that is NOT form fitting. Like what’s the 80’s without wide shoulders and huge shoulder pads? LOL

Well, one of the goals of Seamly is to eventually be able to produce 3D models of a garment… but if you ask me (who’s being doing drafting and pattern making for 40+ years in the costume industry) the idea of that would be able to visualize a pattern and fabric on a body before cutting anything, not to produce an exact 3D model of body. To me that’s a futile task. For ex: As long as brassieres’ have been around it’s taken modern materials, steam and pressure to form a cup that fits VS a series of drafted and sewn pattern pieces. You could draft a cup pattern of a 1000 pieces, and it will never form a perfect spherical curve. My advice at this point in time, would be to pick the brain and learn from your Pro, rather than worrying about finding the perfect pattern system. “Grasshopper - When you can take the pebble from my hand, it will be time for you to leave.” :wink:

That being said… no, other than the project this was forked from, there is no other open source pattern software (that I’m aware of) that even allows you draft far less to measure.


Hello @XRE2020

My ha’penny’s worth…

Aldrich is an excellent starting point to getting to know how to draft patterns and produces a good fit once you understand it fully. It also translates very well into Seamly2D. However, if you’re wanting to make a moulage (skin tight that follows the curves without ease), I’d suggest you look up Gina Renees Designs. She gives some very nice tips on this, but some of her classes come at a price.

Other than that, you can look up the books of old masters on


Thank you! I’m currently wrapping my mind around the possibilities of Seamly2D: the way it is set up is indeed quite ingenuous. I guess it’s up to us, the users, to make it work. I’m an engineer who’s new in learning the art of designing clothes. I already was a frustrated maker of often poor fitting standard patterns. That’s why I’m now taking lessons of a pro in pattern drafting, who also has 40+yrs experience :grin: . I cherish her wisdom and every lesson I have with her, her craftmanship and keen eye is invaluable for learning how to optimise a fitting garment, so I definitely will continue to learn that and built the experience.

But surely modern technology can do more! I agree that a 100% 3D fit with 2D pattern pieces is a mathematical impossibility, so the art is in my opinion to get the best origami construction possible, with the least pieces and well positioned cutlines, so that it follows the body shape as close as reasonably possible. A program can generate that, and I get the impression that the expensive corporate software out there, does just that.

But I guess I’ll have to learn bottom up: I’ll continue to draft patterns using my teachers wisdom ánd I wish to develop better “rules” for all the instances where the pattern systems say for example: “use 1/4 measurement_x + 3cm”. It’s that “+3” that bugs me. Because that parameter is non-proportional and based on average bodies and I don’t know what that average body looks like and how the garment is supposed to fit that body. But if there is somebody out there with better rules, I don’t need to invent anything… If that somebody is out there and willing to share, I love to spar with you!

So thank you all for your replies! You’ve definitely encouraged me to start using Seamly2D ánd continue my lessons. I’m currently using Aldrich in my lessons. So I’ll start puzzling on defining better rules for all the non-proportional values using that system as my starting point and the wisdom of my teacher as validation.


That sounds like Ease. This sounds like a close-fitting, but wearable, amount of ease.

As an engineer you probably realize, (though future readers may not,) that any time you add 12[units] to any circumference you are adding almost 2[units] to the radius of the circle —regardless of its size. So as far as the sloper is concerned any difference is well within standard deviation, & not worth worrying about.

I understand that ease really doesn’t vary within garment type regardless of body type, but I’m not sure I believe that either. However, here are two pages which I think make a decent argument for fixed ease, at least in the knitting community:

I know I have found websites listing the different amounts of ease for different garment types, & if you want me to search ones up for you I probably could, but I expect that you will get better results on your own. (For that matter, knowing to ask your instructor about ease for differing garment types/purposes might be best.)


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Absolute noobie here for this software… but I do a ton of 3d modeling and am trying to apply that parameterized methodology to this parameter-driven program.

Just a thought… if you don’t like the fixed 3cm value for whatever instruction you’re referring to then can you turn that into a percentage based on what you’re looking at? if its 3cm for your 30cm calf or whatever, then its 10%, right? The person with a 31cm calf will have a 3.1cm margin. Does that work for you? So the formula you enter would be “(measurement_x *.25) + measurement_y * .10” or whatever your calculation turns out to be.

I don’t know if someone else with more experience would consider it ‘good practice’, but I’ve done it in a couple costume pieces so far because it made sense. Like here where I want the length to be enough to cover the knee, not the middle of where the knee bends.

It seemed reasonable that would be proportional for most people. So I took what I liked on me, and added that as a percentage to the pattern.
In some other places where I wanted a piece to end between point A and B (the next measurement higher up the leg. I had to calculate as well. Line length = MeasurementLengthA + ((MeasurementLengthB-MeasurementLengthA) / 2)

Again, I may find out that it doesn’t work. Maybe when I get to a basketball player I’ll learn all the height is 90% in the leg bone and the knee is only 4% bigger than my own. But that’s where the “tailoring” versus “patterning” would come in, right?

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@Grace @Douglas @Pneumarian this would be a great place for a discussion on the use of “current_line” in formulas. (e.g. ease could be set to 0.05*current_line)

I have not seen this discussed anywhere and stumbled over it several years ago.

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Not sure I understand the concern?.. the 3cm is (accumulative) ease added to the pattern based on the measurements. For example… I’m plotting out vest patterns that I did in Seamly2D, where say it called for chestscale +1 (inches) on the back and similarly on the front. Chestscale being 1/2 of the chest measurement. So for someone that has a 38 chest, the final vest would sew up to 38in + 4in of ease. The same applied to the waist. In other words the ease is just ease - in this case 4 inches. It’s not meant to be proportional. The only reason I see to make the ease proportional might be if you were making pattern for dolls, where maybe you would want to make it to scale. If you want more or less ease, just change the value. Or better yet, you could use a custom variable - lets call it @Ease. Then instead of hardcoding the measurment_x + 3cm… use measurement_x + @Ease (probably divided by 2 or some number of pieces) . That way you can globally change the ease you want in a garment by just changing 1 variable. Want no ease… just set @Ease to zero.

As far as average bodies… you normally draft according to the body type, or grade rules if you will. Of course you also may have to take into account someone who varies from a given proportional draft, and know how to apply direct measures to it, but that part just comes with years of experience to know how to adjust a pattern. And then there’s the whole thing of adjusting for attitude, but that’s another whole topic. Again referring to the vest pattern I’m working with… I had to draft 2 versions, 1 for a regular type (the ideal men size being 5’-9"", a size 38, and 180 lbs, and 1 for stout- where the the difference between the chest & waist is less than 4in. With that being said, there are avg regular bodies, avg stout bodies, avg corpulent bodes, avg boys, avg women, avg misses, avg petite… etc. Which in itself is all relative to the time period - people are simply bigger on “average” today than 50, 100 years ago. You draft for that body type, with what ever ease you want / need in the garment. And that, again can vary depending on the era of the pattern system. A more modern system is probably going to add more ease in the draft. In any case, the ease is generally a function of style, use, or a persons individual taste. For ex: You could take 2 people with the same exact measurements maybe one likes 2in of ease, while the other likes 4in. Maybe you’re building period costumes for Annie, and the style dictates a tighter fit than would modern suits , where the ease maybe 2" instead of 4-6". In other words the ease has nothing to do with average bodies.

BTW, I might add a bit of advice. Regardless of of how you draft (or drape) a garment - on paper or in whatever digital app, ease no ease, tight fitting, loose fitting, etc… proper and accurate measurements are crucial to a proper fitting garment! It’s an issue I’m dealing with right now… besides the fact it can be somewhat subjective, very few people know how to properly take measurements - even some in professional theatre. Never ask someone what their measurements are… most men don’t know (their wife, girlfriend or mom probably does though :)), and women lie - oh I’m a size 6… yeah, more like a 16. Also asking for a (suit) size maybe irrelevant. For ex. One of the actors I’m working on measures a 47" chest… his form says he wears a 44. Maybe in 2022 you do, but not in the 1940’s. Again it’s that “ease” thing. The worst we get is when the teacher lets the high school kids measure each other. :dizzy_face: And I don’t care to know what you in the clothes you’re currently wearing measure - I’m not making clothes for your (ill fitting?) clothes (with maybe the exception of an overcoat).


Yes, @slspencer mentioned in a topic, a few years ago, measure twice - cut once. And, although I’d heard that many times before, it really brought home the importance of measuring very carefully. It doesn’t matter how many areas you measure to get an excellent fit, but rather, how carefully you measure measurements used to create the pattern.

On the subject of ease… yes… I’ve seen that some people are going over to percentage ease rather than a fixed (e.g. 3cm) ease and this makes sense if you’re working over a large range sizes, however, you will still need to have different percentages for different types of clothing (blouse, light jacket, jacket, coat, etc.).

And then there is movement ease… Which is another subject totally but also one that needs to be taken into account when designing a pattern and involves adding ease to allow for extra movement of body parts, like the arms, and also needs to be considered.

Either way, you will need to have a set table that you start with, so while you’re learning pattern making, you may as well just go with what the instructions tell you.