lua: inventory library

src/maths/util.h

@@ -0,0 +1,49 @@
+#ifndef MATHS_UTIL_H_
+#define MATHS_UTIL_H_
+
+#include <ctime>
+#include <stdint.h>
+
+class PseudoRandom {
+    unsigned short seed;
+public:
+    PseudoRandom(){
+        seed = (unsigned short)time(0);
+    }
+
+    int rand(){
+        seed = (seed + 0x7ed5 + (seed << 6));
+        seed = (seed ^ 0xc23c ^ (seed >> 9));
+        seed = (seed + 0x1656 + (seed << 3));
+        seed = ((seed + 0xa264) ^ (seed << 4));
+        seed = (seed + 0xfd70 - (seed << 3));
+        seed = (seed ^ 0xba49 ^ (seed >> 8));
+
+        return (int)seed;
+    }
+
+    int32_t rand32() {
+        return (rand() << 16) | rand();
+    }
+
+    uint32_t randU32() {
+        return (rand() << 16) | rand();
+    }
+
+    int64_t rand64() {
+        uint64_t x = randU32();
+        uint64_t y = randU32();
+        return (x << 32ULL) | y;
+    }
+
+    void setSeed(int number){
+        seed = ((unsigned short)(number*23729) ^ (unsigned short)(number+16786));
+        rand();
+    }
+    void setSeed(int number1, int number2){
+        seed = (((unsigned short)(number1*23729) | (unsigned short)(number2%16786)) ^ (unsigned short)(number2*number1));
+        rand();
+    }
+};
+
+#endif // MATHS_UTIL_H_