Initial commit

Torque/SDK/engine/core/bitTables.cc

@@ -0,0 +1,25 @@
+//-----------------------------------------------------------------------------
+// Torque Game Engine
+// Copyright (C) GarageGames.com, Inc.
+//-----------------------------------------------------------------------------
+
+#include "core/bitTables.h"
+
+bool     BitTables::mTablesBuilt = false;
+S8       BitTables::mHighBit[256];
+S8       BitTables::mWhichOn[256][8];
+S8       BitTables::mNumOn[256];
+static   BitTables  sBuildTheTables;     // invoke ctor first-time work
+
+BitTables::BitTables()
+{
+   if(! mTablesBuilt){
+      // This code only happens once - it relies on the tables being clear.
+      for( U32 byte = 0; byte < 256; byte++ )
+         for( U32 bit = 0; bit < 8; bit++ )
+            if( byte & (1 << bit) )
+               mHighBit[byte] = (mWhichOn[byte][mNumOn[byte]++] = bit) + 1;
+
+      mTablesBuilt = true;
+   }
+}