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inc/hgl/math/FastTriangle.h

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+#ifndef HGL_ALGORITHM_MATH_FAST_TRIANGLE_FUNCTION_INCLUDE
+#define HGL_ALGORITHM_MATH_FAST_TRIANGLE_FUNCTION_INCLUDE
+
+namespace hgl
+{
+    double Lsin(int angle);                                     ///<低精度sin计算,注意传入的参数为角度而非弧度
+    double Lcos(int angle);                                     ///<低精度cos计算,注意传入的参数为角度而非弧度
+    void Lsincos(int angle, double &s, double &c);              ///<低精度sin+cos计算,注意传入的参数为角度而非弧度
+
+    /**
+     * 低精度atan函数
+     */
+    double inline Latan(double z)
+    {
+        constexpr double n1 = 0.97239411f;
+        constexpr double n2 = -0.19194795f;
+
+        return (n1 + n2 * z * z) * z;
+    }
+
+    double Latan2(double y, double x);                          ///<低精度atan2函数
+}//namespace hgl
+#endif//HGL_ALGORITHM_MATH_FAST_TRIANGLE_FUNCTION_INCLUDE