arc3P arcBulge arcTan arcToBezier bezier4P bezierIntersectionWithLine bezierIsStraight bezierPointDistantFromPoint bezierPointLengthFromStart bezierTanget bsplinesToBeziers crossLineCircle crossTwoCircles cubicSplines cubicSplineToBezier ellipse90ToBezier ellipseToBezier fitBezier FitCubicCallback fitCubicSpline fitCurve fitCurve2 fitCurve3 fitCurve4 gaussJordan lengthOfBezier PtCallback quadBezierToCubic roundRectToBeziers SplineFlags splitBezier triEquations

arcTan() bool mgcurv::arcTan ( const Point2d &  start, const Point2d &  end, const Vector2d &  startTan, Point2d &  center, float &  radius, float *  startAngle = (float*)0, float *  sweepAngle = (float*)0  ) static 给定起点、终点和起点切向，计算圆弧参数 参数 [in] start 圆弧的起点 [in] end 圆弧的终点 [in] startTan 圆弧的起点处的切向矢量 [out] center 圆心 [out] radius 半径 [out] startAngle 填充起始角度，为NULL则忽略该参数 [out] sweepAngle 填充圆弧转角，逆时针为正，为NULL则忽略该参数 返回 是否计算成功 参见 arc3P, arcBulge, arcToBezier 函数调用图: 这是这个函数的调用关系图: