Function drawBorder

src/elements/element.arc.ts:241–290

(
  ctx: CanvasRenderingContext2D,
  element: ArcElement,
  offset: number,
  spacing: number,
  circular: boolean,
)

}

function drawBorder(
  ctx: CanvasRenderingContext2D,
  element: ArcElement,
  offset: number,
  spacing: number,
  circular: boolean,
) {
  const {fullCircles, startAngle, circumference, options} = element;
  const {borderWidth, borderJoinStyle, borderDash, borderDashOffset, borderRadius} = options;
  const inner = options.borderAlign === 'inner';

  if (!borderWidth) {
    return;
  }

  ctx.setLineDash(borderDash || []);
  ctx.lineDashOffset = borderDashOffset;

  if (inner) {
    ctx.lineWidth = borderWidth * 2;
    ctx.lineJoin = borderJoinStyle || 'round';
  } else {
    ctx.lineWidth = borderWidth;
    ctx.lineJoin = borderJoinStyle || 'bevel';
  }

  let endAngle = element.endAngle;
  if (fullCircles) {
    pathArc(ctx, element, offset, spacing, endAngle, circular);
    for (let i = 0; i < fullCircles; ++i) {
      ctx.stroke();
    }
    if (!isNaN(circumference)) {
      endAngle = startAngle + (circumference % TAU || TAU);
    }
  }

  if (inner) {
    clipArc(ctx, element, endAngle);
  }

  if (options.selfJoin && endAngle - startAngle >= PI && borderRadius === 0 && borderJoinStyle !== 'miter') {
    clipSelf(ctx, element, endAngle);
  }

  if (!fullCircles) {
    pathArc(ctx, element, offset, spacing, endAngle, circular);
    ctx.stroke();
  }
}

export interface ArcProps extends Point {
  startAngle: number;