import “../core/noop”;
// TODO Unify this code with d3.geom.polygon area?
var d3_geo_pathAreaSum, d3_geo_pathAreaPolygon, d3_geo_pathArea = {
point: d3_noop, lineStart: d3_noop, lineEnd: d3_noop, // Only count area for polygon rings. polygonStart: function() { d3_geo_pathAreaPolygon = 0; d3_geo_pathArea.lineStart = d3_geo_pathAreaRingStart; }, polygonEnd: function() { d3_geo_pathArea.lineStart = d3_geo_pathArea.lineEnd = d3_geo_pathArea.point = d3_noop; d3_geo_pathAreaSum += Math.abs(d3_geo_pathAreaPolygon / 2); }
};
function d3_geo_pathAreaRingStart() {
var x00, y00, x0, y0; // For the first point, … d3_geo_pathArea.point = function(x, y) { d3_geo_pathArea.point = nextPoint; x00 = x0 = x, y00 = y0 = y; }; // For subsequent points, … function nextPoint(x, y) { d3_geo_pathAreaPolygon += y0 * x - x0 * y; x0 = x, y0 = y; } // For the last point, return to the start. d3_geo_pathArea.lineEnd = function() { nextPoint(x00, y00); };
}