freesewing/packages/brian/src/sleevecap.js

import freesewing from "freesewing";

/** Calculates the differece between actual and optimal sleevecap length
 * Positive values mean sleevecap is longer than armhole
 */
function sleevecapDelta(store) {
  return store.get("sleevecapLength") - store.get("sleevecapTarget");
}

function sleevecapAdjust(store) {
  let delta = sleevecapDelta(store);
  let factor = store.get("sleeveFactor");
  if (delta > 0) factor = factor * 0.98;
  else factor = factor * 1.02;
  store.set("sleeveFactor", factor);
}

function draftSleevecap(part, run) {
  // prettier-ignore
  let {debug, units, store, measurements, options, Point, points, Path, paths} = part.shorthand();
  // Sleeve center axis
  points.centerBiceps = new Point(0, 0);
  points.centerCap = points.centerBiceps.shift(
    90,
    measurements.bicepsCircumference *
      (1 + options.bicepsEase) *
      options.armholeDepthFactor *
      store.get("sleeveFactor")
  );

  // Left and right biceps points, limit impact of sleeveFactor to 25%
  let halfWidth =
    (measurements.bicepsCircumference * (1 + options.bicepsEase)) / 2;
  points.bicepsLeft = points.centerBiceps.shift(
    180,
    halfWidth * options.sleeveWidthGuarantee +
      halfWidth * (1 - options.sleeveWidthGuarantee) * store.get("sleeveFactor")
  );
  points.bicepsRight = points.bicepsLeft.flipX(points.centerBiceps);

  // Pitch points
  let width = points.bicepsRight.x;
  let height = points.centerCap.y;
  points.backPitch = new Point(
    -1 * width * options.sleevecapBackFactorX,
    height * options.sleevecapBackFactorY
  );
  points.frontPitch = new Point(
    width * options.sleevecapFrontFactorX,
    height * options.sleevecapFrontFactorY
  );

  // 4 sleevecap quadrants
  // Base points
  points.capQ1Base = points.frontPitch.shiftFractionTowards(
    points.bicepsRight,
    0.5
  );
  points.capQ2Base = points.frontPitch.shiftFractionTowards(
    points.centerCap,
    0.5
  );
  points.capQ3Base = points.backPitch.shiftFractionTowards(
    points.centerCap,
    0.5
  );
  points.capQ4Base = points.backPitch.shiftFractionTowards(
    points.bicepsLeft,
    0.5
  );
  // Offset points
  let baseOffset = measurements.bicepsCircumference * (1 + options.bicepsEase);
  points.capQ1 = points.capQ1Base.shift(
    points.bicepsRight.angle(points.frontPitch) + 90,
    baseOffset * options.sleevecapQ1Offset
  );
  points.capQ2 = points.capQ2Base.shift(
    points.centerCap.angle(points.frontPitch) + 90,
    baseOffset * options.sleevecapQ2Offset
  );
  points.capQ3 = points.capQ3Base.shift(
    points.centerCap.angle(points.backPitch) - 90,
    baseOffset * options.sleevecapQ3Offset
  );
  points.capQ4 = points.capQ4Base.shift(
    points.bicepsLeft.angle(points.backPitch) - 90,
    baseOffset * options.sleevecapQ4Offset
  );
  // Control points
  points.capQ1Cp1 = points.capQ1.shift(
    points.frontPitch.angle(points.bicepsRight),
    baseOffset * options.sleevecapQ1Spread1
  );
  points.capQ1Cp2 = points.capQ1.shift(
    points.frontPitch.angle(points.bicepsRight),
    baseOffset * options.sleevecapQ1Spread2 * -1
  );
  points.capQ2Cp1 = points.capQ2.shift(
    points.centerCap.angle(points.frontPitch),
    baseOffset * options.sleevecapQ2Spread1
  );
  points.capQ2Cp2 = points.capQ2.shift(
    points.centerCap.angle(points.frontPitch),
    baseOffset * options.sleevecapQ2Spread2 * -1
  );
  points.capQ3Cp1 = points.capQ3.shift(
    points.backPitch.angle(points.centerCap),
    baseOffset * options.sleevecapQ3Spread1
  );
  points.capQ3Cp2 = points.capQ3.shift(
    points.backPitch.angle(points.centerCap),
    baseOffset * options.sleevecapQ3Spread2 * -1
  );
  points.capQ4Cp1 = points.capQ4.shift(
    points.bicepsLeft.angle(points.backPitch),
    baseOffset * options.sleevecapQ4Spread1
  );
  points.capQ4Cp2 = points.capQ4.shift(
    points.bicepsLeft.angle(points.backPitch),
    baseOffset * options.sleevecapQ4Spread2 * -1
  );

  // Sleevecap seamline
  paths.sleevecap = new Path()
    .move(points.bicepsRight)
    .curve(points.bicepsRight, points.capQ1Cp1, points.capQ1)
    .curve(points.capQ1Cp2, points.capQ2Cp1, points.capQ2)
    .curve(points.capQ2Cp2, points.capQ3Cp1, points.capQ3)
    .curve(points.capQ3Cp2, points.capQ4Cp1, points.capQ4)
    .curve(points.capQ4Cp2, points.bicepsLeft, points.bicepsLeft);

  // Store sleevecap length
  store.set("sleevecapLength", paths.sleevecap.length());
  if (run === 1) {
    let armholeLength =
      store.get("frontArmholeLength") + store.get("backArmholeLength");
    let sleevecapEase = armholeLength * options.sleevecapEase;
    store.set("sleevecapEase", sleevecapEase);
    store.set("sleevecapTarget", armholeLength + sleevecapEase);
    debug("Sleevecap ease is", units(sleevecapEase));

    // Uncomment this line to see all sleevecap iterations
    //paths[run] = paths.sleevecap;
  }
}

var sleevecap = {
  draft: function(part) {
    // prettier-ignore
    let {debug, store, units, sa, measurements, options, Point, points, Path, paths } = part.shorthand();

    store.set("sleeveFactor", 1);
    let run = 1;
    do {
      draftSleevecap(part, run);
      debug(
        `Sleevecap draft ${run}, sleevecap delta is ${units(
          sleevecapDelta(store)
        )}`
      );
      sleevecapAdjust(store);
      run++;
    } while (
      options.brianFitSleeve === true &&
      run < 100 &&
      Math.abs(sleevecapDelta(store)) > 2
    );

    // Paths
    paths.sleevecap.attr("class", "fabric");

    // Anchor point for sampling
    points.gridAnchor = new Point(0, 0);

    return part;
  }
};

export default sleevecap;