Ogre的许多外部资源数据都有着相应的脚本格式，现例举如下：
Ogre的资源管理器都是从ResourceManager派生出来的，而ResourceManager又以ScriptLoader为基类。有相应脚本的的资源管理器，在其构造函数中会调用ResourceGroupManager::_registerScriptLoader()函数，将资源管理器对象指针保存到ResourceGroupManager的mScriptLoaderOrderMap容器中。在之后的资源初始化过程中（见前面相关文章的讨论），ResourceGroupManager::initialiseResourceGroup()会调用ResourceGroupManager::parseResourceGroupScripts()函数，对相应ResourceGroup中的脚本文件进行解析。新版本的Ogre引入了ScriptCompilerManager类后，以“.material”、“.program”、“.particle”和“.compositor”为后缀的文件都统一由ScriptCompilerManager类型对象统一进行管理和解析（而原来各自对应的资源管理器不再注册到mScriptLoaderOrderMap中）。ScriptCompilerManager自身也是以ScriptLoader为基类的，Oger在初始化Root对象时，会创建一个ScriptCompilerManager对象，并通过ResourceGroupManager::_registerScriptLoader()函数，将它的指针保存到ResourceGroupManager的mScriptLoaderOrderMap容器中。因此，新版本的ResourceGroupManager的mScriptLoaderOrderMap中保存的第一个ScriptLoader对象，实际上就是ScriptCompilerManager的对象指针。
ResourceGroupManager::parseResourceGroupScripts()函数的代码如下：
1 void ResourceGroupManager::parseResourceGroupScripts(ResourceGroup* grp)
2 {
3
4 LogManager::getSingleton().logMessage(
5 "Parsing scripts for resource group " + grp->name);
6
7 // Count up the number of scripts we have to parse
8 typedef list<FileInfoListPtr>::type FileListList;
9 typedef SharedPtr<FileListList> FileListListPtr;
10 typedef std::pair<ScriptLoader*, FileListListPtr> LoaderFileListPair;
11 typedef list<LoaderFileListPair>::type ScriptLoaderFileList;
12 ScriptLoaderFileList scriptLoaderFileList;
13 size_t scriptCount = 0;
14 // Iterate over script users in loading order and get streams
15 ScriptLoaderOrderMap::iterator oi;
16 for (oi = mScriptLoaderOrderMap.begin();
17 oi != mScriptLoaderOrderMap.end(); ++oi)
18 {
19 ScriptLoader* su = oi->second;
20 // MEMCATEGORY_GENERAL is the only category supported for SharedPtr
21 FileListListPtr fileListList(OGRE_NEW_T(FileListList, MEMCATEGORY_GENERAL)(), SPFM_DELETE_T);
22
23 // Get all the patterns and search them
24 const StringVector& patterns = su->getScriptPatterns();
25 for (StringVector::const_iterator p = patterns.begin(); p != patterns.end(); ++p)
26 {
27 FileInfoListPtr fileList = findResourceFileInfo(grp->name, *p);
28 scriptCount += fileList->size();
29 fileListList->push_back(fileList);
30 }
31 scriptLoaderFileList.push_back(
32 LoaderFileListPair(su, fileListList));
33 }
34 // Fire scripting event
35 fireResourceGroupScriptingStarted(grp->name, scriptCount);
36
37 // Iterate over scripts and parse
38 // Note we respect original ordering
39 for (ScriptLoaderFileList::iterator slfli = scriptLoaderFileList.begin();
40 slfli != scriptLoaderFileList.end(); ++slfli)
41 {
42 ScriptLoader* su = slfli->first;
43 // Iterate over each list
44 for (FileListList::iterator flli = slfli->second->begin(); flli != slfli->second->end(); ++flli)
45 {
46 // Iterate over each item in the list
47 for (FileInfoList::iterator fii = (*flli)->begin(); fii != (*flli)->end(); ++fii)
48 {
49 bool skipScript = false;
50 fireScriptStarted(fii->filename, skipScript);
51 if(skipScript)
52 {
53 LogManager::getSingleton().logMessage(
54 "Skipping script " + fii->filename);
55 }
56 else
57 {
58 LogManager::getSingleton().logMessage(
59 "Parsing script " + fii->filename);
60 DataStreamPtr stream = fii->archive->open(fii->filename);
61 if (!stream.isNull())
62 {
63 if (mLoadingListener)
64 mLoadingListener->resourceStreamOpened(fii->filename, grp->name, 0, stream);
65
66 if(fii->archive->getType() == "FileSystem" && stream->size() <= 1024 * 1024)
67 {
68 DataStreamPtr cachedCopy;
69 cachedCopy.bind(OGRE_NEW MemoryDataStream(stream->getName(), stream));
70 su->parseScript(cachedCopy, grp->name);
71 }
72 else
73 su->parseScript(stream, grp->name);
74 }
75 }
76 fireScriptEnded(fii->filename, skipScript);
77 }
78 }
79 }
80
81 fireResourceGroupScriptingEnded(grp->name);
82 LogManager::getSingleton().logMessage(
83 "Finished parsing scripts for resource group " + grp->name);
84 }
ScriptCompilerManager对象有一个StringVector mScriptPatterns成员，它里面主要保存着待解析的脚本文件类型信息，在ScriptCompilerManager被创建时，“.material”、“.program”、“.particle”、“.compositor”四个字符串会被保存在内。第27行的findResourceFileInfo()函数的代码展开如下：
1 FileInfoListPtr ResourceGroupManager::findResourceFileInfo(const String& groupName,
2 const String& pattern, bool dirs)
3 {
4 OGRE_LOCK_AUTO_MUTEX
5 // MEMCATEGORY_GENERAL is the only category supported for SharedPtr
6 FileInfoListPtr vec(OGRE_NEW_T(FileInfoList, MEMCATEGORY_GENERAL)(), SPFM_DELETE_T);
7
8 // Try to find in resource index first
9 ResourceGroup* grp = getResourceGroup(groupName);
10 if (!grp)
11 {
12 OGRE_EXCEPT(Exception::ERR_ITEM_NOT_FOUND,
13 "Cannot locate a resource group called ‘" + groupName + "‘",
14 "ResourceGroupManager::findResourceFileInfo");
15 }
16
17 OGRE_LOCK_MUTEX(grp->OGRE_AUTO_MUTEX_NAME) // lock group mutex
18
19 // Iterate over the archives
20 LocationList::iterator i, iend;
21 iend = grp->locationList.end();
22 for (i = grp->locationList.begin(); i != iend; ++i)
23 {
24 FileInfoListPtr lst = (*i)->archive->findFileInfo(pattern, (*i)->recursive, dirs);
25 vec->insert(vec->end(), lst->begin(), lst->end());
26 }
27
28 return vec;
29 }
以FileSystemArchive为例，在findResourceFileInfo()函数中的第24行将会形成如下调用链：
1. FileSystemArchive::findFileInfo
||
\/
2. FileSystemArchive::findFiles(const String& pattern, bool recursive,
bool dirs, StringVector* simpleList, FileInfoList* detailList)
其中的调用“结点2”——findFiles()函数展开后为：
1 void FileSystemArchive::findFiles(const String& pattern, bool recursive,
2 bool dirs, StringVector* simpleList, FileInfoList* detailList) const
3 {
4 intptr_t lHandle, res;
5 struct _finddata_t tagData;
6
7 // pattern can contain a directory name, separate it from mask
8 size_t pos1 = pattern.rfind (‘/‘);
9 size_t pos2 = pattern.rfind (‘\\‘);
10 if (pos1 == pattern.npos || ((pos2 != pattern.npos) && (pos1 < pos2)))
11 pos1 = pos2;
12 String directory;
13 if (pos1 != pattern.npos)
14 directory = pattern.substr (0, pos1 + 1);
15
16 String full_pattern = concatenate_path(mName, pattern);
17
18 lHandle = _findfirst(full_pattern.c_str(), &tagData);
19 res = 0;
20 while (lHandle != -1 && res != -1)
21 {
22 if ((dirs == ((tagData.attrib & _A_SUBDIR) != 0)) &&
23 ( !msIgnoreHidden || (tagData.attrib & _A_HIDDEN) == 0 ) &&
24 (!dirs || !is_reserved_dir (tagData.name)))
25 {
26 if (simpleList)
27 {
28 simpleList->push_back(directory + tagData.name);
29 }
30 else if (detailList)
31 {
32 FileInfo fi;
33 fi.archive = this;
34 fi.filename = directory + tagData.name;
35 fi.basename = tagData.name;
36 fi.path = directory;
37 fi.compressedSize = tagData.size;
38 fi.uncompressedSize = tagData.size;
39 detailList->push_back(fi);
40 }
41 }
42 res = _findnext( lHandle, &tagData );
43 }
44 // Close if we found any files
45 if(lHandle != -1)
46 _findclose(lHandle);
47
48 // Now find directories
49 if (recursive)
50 {
51 String base_dir = mName;
52 if (!directory.empty ())
53 {
54 base_dir = concatenate_path(mName, directory);
55 // Remove the last ‘/‘
56 base_dir.erase (base_dir.length () - 1);
57 }
58 base_dir.append ("/*");
59
60 // Remove directory name from pattern
61 String mask ("/");
62 if (pos1 != pattern.npos)
63 mask.append (pattern.substr (pos1 + 1));
64 else
65 mask.append (pattern);
66
67 lHandle = _findfirst(base_dir.c_str (), &tagData);
68 res = 0;
69 while (lHandle != -1 && res != -1)
70 {
71 if ((tagData.attrib & _A_SUBDIR) &&
72 ( !msIgnoreHidden || (tagData.attrib & _A_HIDDEN) == 0 ) &&
73 !is_reserved_dir (tagData.name))
74 {
75 // recurse
76 base_dir = directory;
77 base_dir.append (tagData.name).append (mask);
78 findFiles(base_dir, recursive, dirs, simpleList, detailList);
79 }
80 res = _findnext( lHandle, &tagData );
81 }
82 // Close if we found any files
83 if(lHandle != -1)
84 _findclose(lHandle);
85 }
86 }
其作用是在本Archive指定的目录下搜索以pattern（findFiles的第一个参数）为后缀名的文件，并将满足条件的所有文件的相关信息（包括文件名、相应Archive对象指针、路径名及是否为压缩文件等）添加到名为detailList的FileInfoList中去并返回给调用函数。而ResourceGroupManager::findResourceFileInfo()函数会对保存在本group的locationList中的所有Archive对象进行如上操作（findResourceFileInfo()函数22-26行）。
因此，回到最开始的ResourceGroupManager::parseResourceGroupScripts()函数，可以知道第16-33行的作用是：对指定的resourceGroup进行搜索，并将保存在locationList中的所有Archive对象对应目录下，后缀名为资源管理器指定的文件类型（由mScriptPatterns来指定，对ScriptCompilerManager来说mScriptPattern中的值为：“.material”、“.program”、“.particle”、“.compositor”）的文件的相关信息，以文件为单位保存到scriptLoaderFileList（在第12行中定义）列表中。
ResourceGroupManager::parseResourceGroupScripts()函数的第39-79行，则实现了对保存在scriptLoaderFileList列表中对应的脚本文件的解析。其中最核心的逻辑是DataStreamPtr stream = fii->archive->open(fii->filename)（60行）和su->parseScript()（70、73行）。第60行用于打开待解析的脚本文件，而su->parseScript()函数则会调用相应资源管理器的parseScript(DataStreamPtr& stream, const String& groupName)函数。以ScriptCompilerManager为例，其代码为：
1 void ScriptCompilerManager::parseScript(DataStreamPtr& stream, const String& groupName)
2 {
3 #if OGRE_THREAD_SUPPORT
4 // check we have an instance for this thread (should always have one for main thread)
5 if (!OGRE_THREAD_POINTER_GET(mScriptCompiler))
6 {
7 // create a new instance for this thread - will get deleted when
8 // the thread dies
9 OGRE_THREAD_POINTER_SET(mScriptCompiler, OGRE_NEW ScriptCompiler());
10 }
11 #endif
12 // Set the listener on the compiler before we continue
13 {
14 OGRE_LOCK_AUTO_MUTEX
15 OGRE_THREAD_POINTER_GET(mScriptCompiler)->setListener(mListener);
16 }
17 OGRE_THREAD_POINTER_GET(mScriptCompiler)->compile(stream->getAsString(), stream->getName(), groupName);
18 }
其中，stream->getAsString()用来将脚本文件中的内容以字符串的形式加载到内存；stream->getName()用来返回待解析脚本文件的文件名。
原文：http://www.cnblogs.com/skyofbitbit/p/4089013.html