Update Files

Kha/Sources/kha/audio2/ogg/tools/MathTools.hx

@@ -0,0 +1,36 @@
+package kha.audio2.ogg.tools;
+
+/**
+ * ...
+ * @author shohei909
+ */
+class MathTools
+{
+    public static inline function ilog(n:Int)
+    {
+        var log2_4 = [0, 1, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4];
+        
+        // 2 compares if n < 16, 3 compares otherwise (4 if signed or n > 1<<29)
+        return if (n < (1 << 14)) {
+            if (n < (1 <<  4)) {
+                0 + log2_4[n];
+            } else if (n < (1 << 9)) {
+                5 + log2_4[n >>  5];
+            } else {
+                10 + log2_4[n >> 10];
+            }
+        } else if (n < (1 << 24)) {
+            if (n < (1 << 19)) {
+                15 + log2_4[n >> 15];
+            } else {
+                20 + log2_4[n >> 20];
+            }
+        } else if (n < (1 << 29)) {
+            25 + log2_4[n >> 25];
+        } else if (n < (1 << 31)) {
+            30 + log2_4[n >> 30];
+        } else {
+            0; // signed n returns 0
+        }
+    }
+}