Changeset 8322

Timestamp:

05/14/08 19:03:57

Author:

robert

Message:

Introduced preliminary support for asynchronous file read requests,

ReaderWriter?

ReadResult? now has a FILE_REQUEST enum.

ReaderWriter?

Options now has a s/getAsynchronousFileReadHint() parameter methods.

libcurl based plugin now detects enabing of the AsynchronousFileReadHint?, but
as yet does not handle async requests - handling everything syncronously.

DatabasePager? now by default will enable AsynchronousFileReadHint? for http
based file requests

Files:

• OpenSceneGraph/trunk/include/osgDB/ReaderWriter (modified) (6 diffs)
• OpenSceneGraph/trunk/src/osgDB/DatabasePager.cpp (modified) (2 diffs)
• OpenSceneGraph/trunk/src/osgPlugins/curl/ReaderWriterCURL.cpp (modified) (1 diff)

OpenSceneGraph/trunk/include/osgDB/ReaderWriter

@@ -91 +91 @@
-                Options():
-                    osg::Object(true),
-
+
+
+
-                Options(const std::string& str):
-                    osg::Object(true),
-                    _str(str), 
-
+
+
-                
-                Options(const Options& options,const osg::CopyOp& copyop=osg::CopyOp::SHALLOW_COPY):
@@ -101 +104 @@
-                    _str(options._str),
-                    _databasePaths(options._databasePaths),
-
+
+
-
-                META_Object(osgDB,Options);
@@ -120 +124 @@
-                const FilePathList& getDatabasePathList() const { return _databasePaths; }
-
+
-                /** Set whether the Registry::ObjectCache should be used by default.*/
-                void setObjectCacheHint(CacheHintOptions useObjectCache) { _objectCacheHint = useObjectCache; }
@@ -125 +130 @@
-                /** Get whether the Registry::ObjectCache should be used by default.*/
-                CacheHintOptions getObjectCacheHint() const { return _objectCacheHint; }
+
+
+                /** Set Asynchrnous file read hint. 
+                  * This hint is used by plugins like the libcurl http reader plugin to inform them that
+                  * they should make an internal file read requests to their background threads to load files,
+                  * with the plugin returning immediately with a ReadResult::FILE_REQUESTED status.  It is 
+                  * assumed that calls will continue to be made to the plugin until the background threads
+                  * have read or failed to read the request file, at which point the return status which change
+                  * to FILE_LOADED and the objects will be returned.
+                  * Note, this facility is particular useful when using DatabasePager in conjunction with
+                  * internet based databases where file load latency is relatively high.*/
+                void setAsynchronousFileReadHint(bool flag) { _asynchronousFileReadHint = flag; }
+
+                /** Get Asynchrnous file read hint. */
+                bool getAsynchronousFileReadHint() const { return _asynchronousFileReadHint; }
+
-
-                /** Sets a plugindata value PluginData with a string */
@@ -149 +170 @@
-                FilePathList        _databasePaths;
-                CacheHintOptions    _objectCacheHint;
+                bool                _asynchronousFileReadHint;
-
-                typedef std::map<std::string,void*> PluginDataMap;
@@ -161 +183 @@
-                enum ReadStatus
-                {
-
-
-
-
-
+
+
+
+
+
+
-                };
-

OpenSceneGraph/trunk/src/osgDB/DatabasePager.cpp

@@ -1 +1 @@
-#include <osgDB/DatabasePager>
-#include <osgDB/ReadFile>
+#include <osgDB/FileNameUtils>
-
-#include <osg/Geode>
@@ -420 +421 @@
-            databaseRequest->_priorityLastRequest = priority;
-            databaseRequest->_groupForAddingLoadedSubgraph = group;
-
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-            _fileRequestList.push_back(databaseRequest);

OpenSceneGraph/trunk/src/osgPlugins/curl/ReaderWriterCURL.cpp

@@ -317 +317 @@
-            }
-
+            bool asyncFileRead = options ? options->getAsynchronousFileReadHint() : false;
+            
+            osg::notify(osg::INFO)<<"AsynchronousFileReadHint= "<<asyncFileRead<<std::endl;
+            
+            // if (asyncFileRead) return ReadResult::FILE_REQUESTED;
-        
-            std::stringstream buffer;