Teensy optimisation for esmtool

- Use an unordered_set instead of a list to
  keep track of skipped records.
- Reduce the number of conditions when parsing 4-letters
  records by using a switch-case instead of cascading conditions.
- Add a const

apps/esmtool/esmtool.cpp

@@ -2,6 +2,7 @@
 #include <vector>
 #include <deque>
 #include <list>
+#include <unordered_set>
 #include <map>
 #include <set>
 #include <fstream>
@@ -322,7 +323,7 @@ int load(Arguments& info)
     std::string filename = info.filename;
     std::cout << "Loading file: " << filename << std::endl;
 
-    std::list<uint32_t> skipped;
+    std::unordered_set<uint32_t> skipped;
 
     try {
 
@@ -364,17 +365,17 @@ int load(Arguments& info)
         // Loop through all records
         while(esm.hasMoreRecs())
         {
-            ESM::NAME n = esm.getRecName();
+            const ESM::NAME n = esm.getRecName();
             uint32_t flags;
             esm.getRecHeader(flags);
 
             EsmTool::RecordBase *record = EsmTool::RecordBase::create(n);
             if (record == nullptr)
             {
-                if (std::find(skipped.begin(), skipped.end(), n.intval) == skipped.end())
+                if (skipped.count(n.intval) == 0)
                 {
                     std::cout << "Skipping " << n.toString() << " records." << std::endl;
-                    skipped.push_back(n.intval);
+                    skipped.emplace(n.intval);
                 }
 
                 esm.skipRecord();

apps/esmtool/record.cpp

@@ -172,7 +172,7 @@ void printTransport(const std::vector<ESM::Transport::Dest>& transport)
 namespace EsmTool {
 
 RecordBase *
-RecordBase::create(ESM::NAME type)
+RecordBase::create(const ESM::NAME type)
 {
     RecordBase *record = nullptr;
 

components/esm/esmcommon.hpp

@@ -110,15 +110,14 @@ struct FIXED_STRING<4> : public FIXED_STRING_BASE<FIXED_STRING, 4>
     void assign(const std::string& value)
     {
         intval = 0;
-        size_t length = value.size();
-        if (length == 0) return;
-        data[0] = value[0];
-        if (length == 1) return;
-        data[1] = value[1];
-        if (length == 2) return;
-        data[2] = value[2];
-        if (length == 3) return;
-        data[3] = value[3];
+        switch(value.size()) {
+            case 4: data[3] = value[3];
+            case 3: data[2] = value[2];
+            case 2: data[1] = value[1];
+            case 1: data[0] = value[0];
+            default: break;
+        }
+
     }
 
     char const* ro_data() const { return data; }

components/esm/esmreader.cpp

@@ -373,7 +373,7 @@ void ESMReader::setEncoder(ToUTF8::Utf8Encoder* encoder)
     mEncoder = encoder;
 }
 
-size_t ESMReader::getFileOffset()
+size_t ESMReader::getFileOffset() const
 {
     return mEsm->tellg();
 }

components/esm/esmreader.hpp

@@ -73,7 +73,7 @@ public:
   void openRaw(const std::string &filename);
 
   /// Get the current position in the file. Make sure that the file has been opened!
-  size_t getFileOffset();
+  size_t getFileOffset() const;
 
   // This is a quick hack for multiple esm/esp files. Each plugin introduces its own
   //  terrain palette, but ESMReader does not pass a reference to the correct plugin