src/classes/sigma.classes.edgequad.js
function(e, cp) {
      var pt = sigma.utils.getPointOnQuadraticCurve(
        0.5,
        e.x1,
        e.y1,
        e.x2,
        e.y2,
        cp.x,
        cp.y
      );

      // Bounding box of the two points and the point at the middle of the
      // curve:
      var minX = Math.min(e.x1, e.x2, pt.x),
          maxX = Math.max(e.x1, e.x2, pt.x),
          minY = Math.min(e.y1, e.y2, pt.y),
          maxY = Math.max(e.y1, e.y2, pt.y);

      return {
        x1: minX - e.size,
        y1: minY - e.size,
        x2: maxX + e.size,
        y2: minY - e.size,
        height: maxY - minY + e.size * 2
      };
    }
function(e, cp) {
      var pt = sigma.utils.getPointOnQuadraticCurve(
        0.5,
        e.x1,
        e.y1,
        e.x2,
        e.y2,
        cp.x,
        cp.y
      );

      // Bounding box of the two points and the point at the middle of the
      // curve:
      var minX = Math.min(e.x1, e.x2, pt.x),
          maxX = Math.max(e.x1, e.x2, pt.x),
          minY = Math.min(e.y1, e.y2, pt.y),
          maxY = Math.max(e.y1, e.y2, pt.y);

      return {
        x1: minX - e.size,
        y1: minY - e.size,
        x2: maxX + e.size,
        y2: minY - e.size,
        height: maxY - minY + e.size * 2
      };
    }
function ( e , cp ) { var pt = sigma . utils . getPointOnQuadraticCurve ( 0.5 , e . x1 , e . y1 , e . x2 , e . y2 , cp . x , cp . y ) ; // Bounding box of the two points and the point at the middle of the // curve: var minX = Math . min ( e . x1 , e . x2 , pt . x ) , maxX = Math . max ( e . x1 , e . x2 , pt . x ) , minY = Math . min ( e . y1 , e . y2 , pt . y ) , maxY = Math . max ( e . y1 , e . y2 , pt . y ) ; return { x1 : minX - e . size , y1 : minY - e . size , x2 : maxX + e . size , y2 : minY - e . size , height : maxY - minY + e . size * 2 } ; }
Transforms a graph edge of type 'curve' with x1, y1, x2, y2,
control point and size into an axis-aligned square.

@param  {object} e  A graph edge with at least two points
(x1, y1), (x2, y2) and a size.
@param  {object} cp A control point (x,y).
@return {object}    A square: two points (x1, y1), (x2, y2) and height.
Transforms a graph edge of type curve with x1 y1 x2 y2 control point and size into an axis - aligned square .