initial version ( megaglest 3.2.3-beta3 )

source/shared_lib/sources/util/random.cpp

@@ -0,0 +1,46 @@
+#include "random.h"
+
+#include <cassert>
+
+#include "leak_dumper.h"
+
+namespace Shared{ namespace Util{
+
+// =====================================================
+//	class Random
+// =====================================================
+
+const int Random::m= 714025;
+const int Random::a= 1366;
+const int Random::b= 150889;
+
+Random::Random(){
+	lastNumber= 0;
+}
+
+void Random::init(int seed){
+	lastNumber= seed % m;
+}
+
+int Random::rand(){
+	lastNumber= (a*lastNumber + b) % m;
+	return lastNumber;
+}
+
+int Random::randRange(int min, int max){
+	assert(min<=max);
+	int diff= max-min;
+	int res= min + static_cast<int>(static_cast<float>(diff+1)*Random::rand() / m);
+	assert(res>=min && res<=max);
+	return res;
+}
+
+float Random::randRange(float min, float max){
+	assert(min<=max);
+	float rand01= static_cast<float>(Random::rand())/(m-1);
+	float res= min+(max-min)*rand01;
+	assert(res>=min && res<=max);
+	return res;
+}
+
+}}//end namespace