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---
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2022-03-27 17:21:32 +02:00
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title: "Brian body block: Design Options"
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2021-10-17 18:26:00 +02:00
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---
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<PatternOptions pattern='brian' />
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## Understanding the sleevecap
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In version 2 of FreeSewing, the sleevecap of Brian was redesigned to be more adaptable to
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different types of sleeves and garments. As a result, the sleevecap alone now has 20 options
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to control its shape. Whereas that may seem a bit overwhelming at first, understanding how the
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sleevecap is drafted makes it easy to understand what all the individual options do.
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### The bounding box
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The _bounding box_ of the sleevecap is a rectangle that is as wide as the sleeve, and
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as high as the sleevecap. Inside this box, we will construct our sleevecap later.
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The image above shows a sleevecap, starting at point 1, then going up until point 4,
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and then down again to point 2.
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<Note>
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###### Finding out which is the front of the sleeve(cap)
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In our example, the front of the sleevecap is on the right hand side. But how would you know?
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While patterns typically have an indication that shows which side is which (a single notch
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means the front, whereas a double notch means the back), you can also
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recognize the front side of a sleevecap because it is more curved. The backside of the
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sleevecap will also be curved, but it's a flatter curve. That's because the human shoulder
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is more pronounced and curved on the front of the body, thus the sleevecap is more curved
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there to fit the shoulder.
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</Note>
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The width of the sleevecap (and thus the width of the sleeve at the bottom of the armhole)
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is equal to the distance between points 1 and 2. That distance depends on the measurements
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of the model, the amount of ease, the cut of the garment and so on. For our sleevecap, all we
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need to know is that we start with a given width. And while that width can be influenced by
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other factors, we can not influence it by any of the sleevecap options.
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The height of the sleevecap is equal to the distance between points 3 and 4. The exact height
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is a trade-off between the measurments of the model, options, ease, sleevecap ease, and the fact
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that the sleeve ultimately has to fit the armhole. So the height may vary, and we don't control
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the exact value. But there are two options that control the shape of our sleevecap:
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- [Sleevecap top X](/docs/patterns/brian/options/sleevecaptopfactorx/) : Controls the horizontal placement of point 3 and 4
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- [Sleevecap top Y](/docs/patterns/brian/options/sleevecaptopfactory/) : Controls the vertical placement of point 4
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In other words, point 4 can be made higher and lower and, perhaps less intutitively, it can also
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be changed to lie more to the right or the left, rather than smack in the middle as in our example.
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### The inflection points
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With points 1, 2, 3, and 4 in place, we have a box to draw our sleevecap in. Now it's time to
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map out our _inflection points_. These are points 5 and 6 on our drawing, and their placement
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is determined by the following 4 options:
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- [Sleevecap back X](/docs/patterns/brian/options/sleevecapbackfactorx) : Controls the horizontal placement of point 5
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- [Sleevecap back Y](/docs/patterns/brian/options/sleevecapbackfactory) : Controls the vertical placement of point 5
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- [Sleevecap front X](/docs/patterns/brian/options/sleevecapbackfactorx) : Controls the horizontal placement of point 6
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- [Sleevecap front Y](/docs/patterns/brian/options/sleevecapbackfactory) : Controls the vertical placement of point 6
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<Note>
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As you see in our example, these points do not always lie on our sleevecap line. Instead, they
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are instrumental in creating the points that always lie on the sleevecap: the anchor points.
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</Note>
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### The anchor points
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Ultimately, our sleevecap will be the combination of 5 curves. In addition to points 1 and 2,
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the four _anchor points_ that are marked in orange in our example will be the start/finish of
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those curves.
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The points are _offset_ perpendicular from the middle of a line between the two anchor points
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surrounding them. The offset for each point is controlled by these 4 options:
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- [Sleevecap Q1 offset](/docs/patterns/brian/options/sleevecapq1offset) : Controls the offset perpendicular to the line from points 2 to 6
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- [Sleevecap Q2 offset](/docs/patterns/brian/options/sleevecapq2offset) : Controls the offset perpendicular to the line from points 6 to 4
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- [Sleevecap Q3 offset](/docs/patterns/brian/options/sleevecapq3offset) : Controls the offset perpendicular to the line from points 4 to 5
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- [Sleevecap Q4 offset](/docs/patterns/brian/options/sleevecapq3offset) : Controls the offset perpendicular to the line from points 5 to 1
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<Note>
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We've divided our sleevecap into 4 quarters. We start at the front (the right in our example)
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with quarter 1, and make our way to the back to end with quarter 4.
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Like the offset option, the last options to determine the shape of our sleevecap will just repeat so you can
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control each quarter individually.
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</Note>
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### The spread
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We now have all the start and end points to draw the 5 curves that will make up our sleevecaps.
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What we're missing are the control points
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(see [our info on Bézier curves](https://freesewing.dev/concepts/beziercurves) to learn more
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about how curves are constructed). These are determined by the so-called _spread_.
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For each of the anchor points (the ones marked in orange, not points 1 and 2) there is an option
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to control the spread upwards, and downwards:
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- [Sleevecap Q1 downward spread](/docs/patterns/brian/options/sleevecapq1spread1) : Controls the downward spread in the first quarter
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- [Sleevecap Q1 upward spread](/docs/patterns/brian/options/sleevecapq1spread2) : Controls the upward spread in the first quarter
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- [Sleevecap Q2 downward spread](/docs/patterns/brian/options/sleevecapq2spread1) : Controls the downward spread in the second quarter
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- [Sleevecap Q2 upward spread](/docs/patterns/brian/options/sleevecapq2spread2) : Controls the upward spread in the second quarter
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- [Sleevecap Q3 upward spread](/docs/patterns/brian/options/sleevecapq3spread1) : Controls the upward spread in the third quarter
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- [Sleevecap Q3 downward spread](/docs/patterns/brian/options/sleevecapq3spread2) : Controls the downward spread in the third quarter
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- [Sleevecap Q4 upward spread](/docs/patterns/brian/options/sleevecapq4spread1) : Controls the upward spread in the fourth quarter
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- [Sleevecap Q4 downward spread](/docs/patterns/brian/options/sleevecapq4spread2) : Controls the downward spread in the fourth quarter
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<Note>
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Attentive readers will have noticed that point 4 is not an anchor point. In other words, there is no guarantee
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that it will lie on the sleevecap line. Which also means that the upwards spread in quarters 2 and 3 will influence
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the height of the sleevecap. Reduce the upwards spread, and the curve will dip below point 4. Increase it and
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the curve will rise above it.
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</Note>
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### Takeaways
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2022-02-19 08:08:58 +01:00
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While the sleevecap in Brian (and all patterns that extend Brian) have a lot of options, understanding how the
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sleevecap is constructed can help you design the exact sleevecap shape you want. To do so:
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- Start with placing the top of your sleevecap
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- Then determine the inflection points
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- Next, use the offset to control the steepness of the curve
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- Finally, use the spread to smooth things out
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What's important to remember is that you're only ever controlling the shape of the sleevecap.
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Whatever shape you design, it will be fitted to the armhole, meaning that its size can and will be adapted
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to make sure the sleeve fits the armscye. However, the shape you design will always be respected.
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