From Eric Sokolowski and Robert Osfield, moved command line option usage setup

from osgviewer example into osg::ArgumentParser and osgViewer::Viewer to make
them more universally available.

applications/osgviewer/osgviewer.cpp

@@ -39,27 +39,15 @@ int main(int argc, char** argv)
     arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+" [options] filename ...");
     arguments.getApplicationUsage()->addCommandLineOption("--image <filename>","Load an image and render it on a quad");
     arguments.getApplicationUsage()->addCommandLineOption("--dem <filename>","Load an image/DEM and render it on a HeightField");
-    arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display command line parameters");
-    arguments.getApplicationUsage()->addCommandLineOption("--help-env","Display environmental variables available");
-    arguments.getApplicationUsage()->addCommandLineOption("--help-keys","Display keyboard & mouse bindings available");
-    arguments.getApplicationUsage()->addCommandLineOption("--help-all","Display all command line, env vars and keyboard & mouse bindings.");
-    arguments.getApplicationUsage()->addCommandLineOption("--SingleThreaded","Select SingleThreaded threading model for viewer.");
-    arguments.getApplicationUsage()->addCommandLineOption("--CullDrawThreadPerContext","Select CullDrawThreadPerContext threading model for viewer.");
-    arguments.getApplicationUsage()->addCommandLineOption("--DrawThreadPerContext","Select DrawThreadPerContext threading model for viewer.");
-    arguments.getApplicationUsage()->addCommandLineOption("--CullThreadPerCameraDrawThreadPerContext","Select CullThreadPerCameraDrawThreadPerContext threading model for viewer.");
 
-    // if user request help write it out to cout.
+    osgViewer::Viewer viewer(arguments);
-    bool helpAll = arguments.read("--help-all");
+
-    unsigned int helpType = ((helpAll || arguments.read("-h") || arguments.read("--help"))? osg::ApplicationUsage::COMMAND_LINE_OPTION : 0 ) |
+    unsigned int helpType = 0;
-                            ((helpAll ||  arguments.read("--help-env"))? osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE : 0 ) |
+    if ((helpType = arguments.readHelpType()))
-                            ((helpAll ||  arguments.read("--help-keys"))? osg::ApplicationUsage::KEYBOARD_MOUSE_BINDING : 0 );
-    if (helpType)
     {
         arguments.getApplicationUsage()->write(std::cout, helpType);
         return 1;
     }
-
-    osgViewer::Viewer viewer(arguments);
     
     // report any errors if they have occurred when parsing the program arguments.
     if (arguments.errors())

include/osg/ApplicationUsage

@@ -43,9 +43,11 @@ class OSG_EXPORT ApplicationUsage : public osg::Referenced
 
         enum Type
         {
+            NO_HELP = 0x0,
             COMMAND_LINE_OPTION = 0x1,
             ENVIRONMENTAL_VARIABLE = 0x2,
-            KEYBOARD_MOUSE_BINDING = 0x4
+            KEYBOARD_MOUSE_BINDING = 0x4,
+            HELP_ALL = KEYBOARD_MOUSE_BINDING|ENVIRONMENTAL_VARIABLE|COMMAND_LINE_OPTION
         };
         
         void addUsageExplanation(Type type,const std::string& option,const std::string& explanation);

include/osg/ArgumentParser

@@ -190,6 +190,14 @@ class OSG_EXPORT ArgumentParser
         /** Write error messages to the given ostream, if at or above the given severity. */
         void writeErrorMessages(std::ostream& output,ErrorSeverity sevrity=BENIGN);
 
+        
+        /** This convinience method handles help requests on the command line.
+          * Return the type(s) of help requested. The return value of this
+          * function is suitable for passing into getApplicationUsage()->write().
+          * If ApplicationUsage::NO_HELP is returned then no help commandline option 
+          * was found on the command line. */
+        ApplicationUsage::Type readHelpType();
+
   
   protected:
         

src/osg/ArgumentParser.cpp

@@ -630,3 +630,19 @@ void ArgumentParser::writeErrorMessages(std::ostream& output,ErrorSeverity sever
         }
     }
 }
+
+ApplicationUsage::Type ArgumentParser::readHelpType() 
+{
+    getApplicationUsage()->addCommandLineOption("-h or --help","Display command line parameters");
+    getApplicationUsage()->addCommandLineOption("--help-env","Display environmental variables available");
+    getApplicationUsage()->addCommandLineOption("--help-keys","Display keyboard & mouse bindings available");
+    getApplicationUsage()->addCommandLineOption("--help-all","Display all command line, env vars and keyboard & mouse bindings.");
+
+    // if user request help write it out to cout.
+    if (read("--help-all"))             return ApplicationUsage::HELP_ALL;
+    if (read("-h") || read("--help"))   return ApplicationUsage::COMMAND_LINE_OPTION;
+    if (read("--help-env"))             return ApplicationUsage::ENVIRONMENTAL_VARIABLE;
+    if (read("--help-keys"))            return ApplicationUsage::KEYBOARD_MOUSE_BINDING;
+
+    return ApplicationUsage::NO_HELP;
+}

src/osgViewer/Viewer.cpp

@@ -43,6 +43,21 @@ Viewer::Viewer(osg::ArgumentParser& arguments)
     _viewerBase = this;
 
     constructorInit();
+
+    // Add help for command-line options read here
+    arguments.getApplicationUsage()->addCommandLineOption("--SingleThreaded","Select SingleThreaded threading model for viewer.");
+    arguments.getApplicationUsage()->addCommandLineOption("--CullDrawThreadPerContext","Select CullDrawThreadPerContext threading model for viewer.");
+    arguments.getApplicationUsage()->addCommandLineOption("--DrawThreadPerContext","Select DrawThreadPerContext threading model for viewer.");
+    arguments.getApplicationUsage()->addCommandLineOption("--CullThreadPerCameraDrawThreadPerContext","Select CullThreadPerCameraDrawThreadPerContext threading model for viewer.");
+    arguments.getApplicationUsage()->addCommandLineOption("--clear-color <color>","Set the background color of the viewer in the form \"r,g,b[,a]\".");
+    arguments.getApplicationUsage()->addCommandLineOption("--screen <num>","Set the screen to use when multiple screens are present.");
+    arguments.getApplicationUsage()->addCommandLineOption("--window <x y w h>","Set the position (x,y) and size (w,h) of the viewer window.");
+    // FIXME: Uncomment these lines when the options have been documented properly
+    //arguments.getApplicationUsage()->addCommandLineOption("--3d-sd","");
+    //arguments.getApplicationUsage()->addCommandLineOption("--panoramic-sd","");
+    //arguments.getApplicationUsage()->addCommandLineOption("--radius","");
+    //arguments.getApplicationUsage()->addCommandLineOption("--collar","");
+    //arguments.getApplicationUsage()->addCommandLineOption("--im","");
     
     std::string filename;
     bool readConfig = false;