Touch

Touch Heightlight

LineChart,BarChart,PositiveNegativeBarChart,PieChart.

implementation

/// 计算点是否在多边形内
- (BOOL)containPoint:(NSValue *)pointValue
              Points:(NSMutableArray<NSValue *> *)pointsArray {
  float vertx[4] = {0, 0, 0, 0};
  float verty[4] = {0, 0, 0, 0};
  CGPoint targetPoint = pointValue.CGPointValue;
  unsigned i = 0;
  for (i = 0; i < pointsArray.count; i = i + 1) {
    CGPoint point1 = pointsArray[i].CGPointValue;
    vertx[i] = point1.x;
    verty[i] = point1.y;
  }
  return pnpoly(4, vertx, verty, targetPoint.x, targetPoint.y);
}
// 判断算法
int pnpoly(int nvert, float *vertx, float *verty, float testx, float testy) {
  int i, j, c = 0;
  for (i = 0, j = nvert - 1; i < nvert; j = i++) {
    if (((verty[i] > testy) != (verty[j] > testy)) &&
        (testx <
         (vertx[j] - vertx[i]) * (testy - verty[i]) / (verty[j] - verty[i]) +
             vertx[i]))
      c = !c;
  }
  return c;
}

LineChart implementation

Use four point describe each section in a line.

Use expand rect area find the nearest line. :)

expand rect area detect implementation