PointsPrimitivePtr mergePoints( const std::vector<const PointsPrimitive *> &pointsPrimitives )
{
size_t totalPointCount = 0;
typedef std::map<std::string, IECore::TypeId> FoundPrimvars;
FoundPrimvars foundPrimvars;
PrimitiveVariableMap constantPrimVars;
std::vector<PointsPrimitivePtr> validatedPointsPrimitives( pointsPrimitives.size() );
// find out which primvars can be merged
for( size_t i = 0; i < pointsPrimitives.size(); ++i )
{
PointsPrimitivePtr pointsPrimitive = validatedPointsPrimitives[i] = pointsPrimitives[i]->copy();
totalPointCount += pointsPrimitive->getNumPoints();
PrimitiveVariableMap &variables = pointsPrimitive->variables;
for( PrimitiveVariableMap::iterator it = variables.begin(); it != variables.end(); ++it )
{
DataPtr data = it->second.data;
const IECore::TypeId typeId = data->typeId();
PrimitiveVariable::Interpolation interpolation = it->second.interpolation;
const std::string &name = it->first;
bool bExistingConstant = constantPrimVars.find( name ) != constantPrimVars.end();
FoundPrimvars::const_iterator fIt = foundPrimvars.find( name );
bool bExistingVertex = fIt != foundPrimvars.end();
if( interpolation == PrimitiveVariable::Constant )
{
if( bExistingVertex )
{
std::string msg = boost::str( boost::format( "PointsAlgo::mergePoints mismatching primvar %s" ) % name );
throw InvalidArgumentException( msg );
}
if( !bExistingConstant )
{
constantPrimVars[name] = it->second;
}
continue;
}
if( interpolation == PrimitiveVariable::Vertex )
{
PrimitiveVariableMap::const_iterator constantPrimVarIt = constantPrimVars.find( name );
if( constantPrimVarIt != constantPrimVars.end() )
{
std::string msg = boost::str( boost::format( "PointsAlgo::mergePoints mismatching primvar %s" ) % name );
throw InvalidArgumentException( msg );
}
if( !bExistingVertex )
{
foundPrimvars[name] = typeId;
}
else
{
if( fIt->second != typeId )
{
DataCastOpPtr castOp = new DataCastOp();
castOp->objectParameter()->setValue( data );
castOp->targetTypeParameter()->setNumericValue( fIt->second );
try
{
it->second.data = runTimeCast<Data>( castOp->operate() );
}
catch( const IECore::Exception &e )
{
std::string msg = boost::str( boost::format( "PointsAlgo::mergePoints unable to cast primvar %s (%s) " ) % name % e.what() );
throw InvalidArgumentException( msg );
}
}
}
}
}
}
// allocate the new points primitive and copy the primvars
PointsPrimitivePtr newPoints = new PointsPrimitive( totalPointCount );
// copy constant primvars
for( PrimitiveVariableMap::const_iterator it = constantPrimVars.begin(); it != constantPrimVars.end(); ++it )
{
newPoints->variables[it->first] = it->second;
}
// merge vertex primvars
for( FoundPrimvars::const_iterator it = foundPrimvars.begin(); it != foundPrimvars.end(); ++it )
{
DataPtr mergedData = mergePrimVars( validatedPointsPrimitives, it->first, totalPointCount );
newPoints->variables[it->first] = PrimitiveVariable( PrimitiveVariable::Vertex, mergedData );
}
return newPoints;
}
