// PerformVariableSubstitutions
//------------------------------------------------------------------------------
/*static*/ bool BFFParser::PerformVariableSubstitutions( const BFFIterator & startIter,
const BFFIterator & endIter,
AString & value )
{
AStackString< 4096 > output;
BFFIterator src( startIter );
BFFIterator end( endIter );
while ( src < end )
{
switch ( *src )
{
case '^':
{
src++; // skip escape char
if ( src < end )
{
output += *src; // append escaped character
}
break;
}
case '$':
{
BFFIterator firstToken( src );
src++; // skip opening $
// find matching $
BFFIterator startName( src );
const char * endName = nullptr;
while ( src < end )
{
if ( *src == '$' )
{
endName = src.GetCurrent();
break;
}
src++;
}
if ( ( endName == nullptr ) ||
( ( endName - startName.GetCurrent() ) < 1 ) )
{
Error::Error_1028_MissingVariableSubstitutionEnd( firstToken );
return false;
}
AStackString< MAX_VARIABLE_NAME_LENGTH > varName( startName.GetCurrent(), endName );
const BFFVariable * var = BFFStackFrame::GetVarAny( varName );
if ( var == nullptr )
{
Error::Error_1009_UnknownVariable( startName, nullptr );
return false;
}
if ( var->IsString() == false )
{
Error::Error_1029_VariableForSubstitutionIsNotAString( startName, varName, var->GetType() );
return false;
}
output += var->GetString();
break;
}
default:
{
output += *src;
break;
}
}
src++;
}
value = output;
return true;
}
int main(int argc, char *argv[])
{
// use an ArgumentParser object to manage the program arguments.
osg::ArgumentParser arguments(&argc,argv);
// set up the usage document, in case we need to print out how to use this program.
arguments.getApplicationUsage()->setDescription(arguments.getApplicationName()+" is the example which demonstrates ping pong rendering with FBOs and mutliple rendering branches. It uses Conway's Game of Life to illustrate the concept.");
arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+" [options] --startim start_image");
arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display this information");
arguments.getApplicationUsage()->addCommandLineOption("--startim","The initial image to seed the game of life with.");
// if user request help write it out to cout.
if (arguments.read("-h") || arguments.read("--help"))
{
arguments.getApplicationUsage()->write(std::cout);
return 1;
}
std::string startName("");
while(arguments.read("--startim", startName)) {}
if (startName == "") {
arguments.getApplicationUsage()->write(std::cout);
return 1;
}
// load the image
osg::ref_ptr<osg::Image> startIm = osgDB::readImageFile(startName);
if (!startIm) {
std::cout << "Could not load start image.\n";
return(1);
}
osg::Node* scene = createScene(startIm.get());
// construct the viewer.
osgViewer::Viewer viewer;
viewer.setThreadingModel(osgViewer::Viewer::SingleThreaded);
// add the stats handler
viewer.addEventHandler(new osgViewer::StatsHandler);
viewer.setSceneData(scene);
viewer.realize();
viewer.setCameraManipulator( new osgGA::TrackballManipulator );
while(!viewer.done())
{
viewer.frame();
// flip the textures after we've completed a frame
golpass->flip();
// attach the proper output to view
geomss->setTextureAttributeAndModes(0,
golpass->getOutputTexture().get(),
osg::StateAttribute::ON);
}
return 0;
}
