test perf fastTan

test/gtx/gtx_fast_trigonometry.cpp

@@ -54,12 +54,35 @@ namespace fastSin{
 	}
 }
 
+namespace fastTan{
+	int perf()
+	{
+		const float begin = -glm::pi<float>();
+		const float end = glm::pi<float>();
+		float result = 0.f;
+		const std::clock_t timestamp1 = std::clock();
+		for (float i = begin; i<end; i = nextafterf(i, end))
+			result = glm::fastTan(i);
+		const std::clock_t timestamp2 = std::clock();
+		for (float i = begin; i<end; i = nextafterf(i, end))
+			result = glm::tan(i);
+		const std::clock_t timestamp3 = std::clock();
+		const std::clock_t time_fast = timestamp2 - timestamp1;
+		const std::clock_t time_default = timestamp3 - timestamp2;
+		std::printf("fastTan Time %d clocks\n", static_cast<unsigned int>(time_fast));
+		std::printf("tan Time %d clocks\n", static_cast<unsigned int>(time_default));
+		return time_fast < time_default ? 0 : 1;
+	}
+}
+
+
 int main()
 {
 	int Error(0);
 
 	Error += ::fastCos::perf();
 	Error += ::fastSin::perf();
+	Error += ::fastTan::perf();
 
 	return Error;
 }