Add JsonValuesPropertyView

Shows the min, max and full values array as a json object inside a file
called "json". eg:

	$ cat .ops/json
    {
        "values" : [ 16, 32, 32, 32, 0 ],
        "max" : 32,
        "min" : 0
    }

src/JsonValuesPropertyView.hh

@@ -0,0 +1,179 @@
+#ifndef ALEMBICFS_JSONVALUESPROPERTYVIEW_HH
+#define ALEMBICFS_JSONVALUESPROPERTYVIEW_HH
+
+#include "PropertyHandler.hh"
+#include "PropertyView.hh"
+#include "OutputTrait.hh"
+
+#include <sys/stat.h>
+
+class Separator
+{
+public:
+
+    Separator( const std::string& sep, size_t count )
+     : m_count( count ), m_sep( sep ) {}
+
+    friend std::ostream& operator<<( std::ostream& os, Separator& separator );
+
+private:
+
+    size_t m_count;
+    const std::string m_sep;
+};
+
+std::ostream& operator<<( std::ostream& os, Separator& separator )
+{
+    if ( separator.m_count <= 1 )
+    {
+        return os;
+    }
+
+    separator.m_count -= 1;
+
+    os << separator.m_sep;
+    return os;
+}
+
+class JsonValuesPropertyView : public PropertyView
+{
+public:
+
+    void getAttr( struct stat* statbuf )
+    {
+        statbuf->st_mode = S_IFREG | S_IRUSR;
+        statbuf->st_size = 4096;
+    }
+
+    template< typename TYPE >
+    struct JsonValuesScalarOp
+    {
+        int operator()(
+                char *buf,
+                const Alembic::Abc::CompoundPropertyReaderPtr ptr,
+                const std::string& propertyName,
+                const Alembic::Abc::uint8_t extent
+                )
+        {
+            Alembic::Abc::BasePropertyReaderPtr vals = ptr->getScalarProperty( propertyName );
+
+            std::vector< TYPE > data( extent );
+
+            vals->asScalarPtr()->getSample( 0, &(data.front()) );
+
+            std::ostringstream stream;
+
+            typename OutputTrait< TYPE >::output_type min
+                = std::numeric_limits< typename OutputTrait< TYPE >::output_type >::max();
+
+            typename OutputTrait< TYPE >::output_type max
+                = std::numeric_limits< typename OutputTrait< TYPE >::output_type >::min();
+
+            Separator separator( ", ", extent );
+
+            stream << "{" << std::endl;
+            stream << "    \"values\" : [ ";
+
+            for ( uint32_t i = 0; i < extent; ++i )
+            {
+                stream << typename OutputTrait< TYPE >::output_type( data[ i ] ) << separator;
+
+                min = std::min(
+                        typename OutputTrait< TYPE >::output_type( data[ i ] ),
+                        min 
+                        );
+
+                max = std::max(
+                        typename OutputTrait< TYPE >::output_type( data[ i ] ),
+                        max 
+                        );
+            }
+
+            stream << " ]," << std::endl;
+
+            stream << "    \"max\" : " << max << "," << std::endl;
+            stream << "    \"min\" : " << min << std::endl;
+
+            stream << "}" << std::endl;
+
+            sprintf( buf, "%s", stream.str().c_str() );
+
+            return stream.str().size();
+        }
+    };
+
+
+    template< typename TYPE >
+    struct JsonValuesArrayOp
+    {
+        int operator()(
+                char *buf,
+                const Alembic::Abc::CompoundPropertyReaderPtr ptr,
+                const std::string& propertyName
+                )
+        {
+            Alembic::Abc::BasePropertyReaderPtr vals = ptr->getProperty(
+                    propertyName
+                    );
+
+            Alembic::Abc::ArraySamplePtr arraySamplePtr;
+            vals->asArrayPtr()->getSample( 0, arraySamplePtr );
+
+            size_t numVals = arraySamplePtr->getDimensions().numPoints();
+            TYPE* data = (TYPE *)(arraySamplePtr->getData());
+
+            std::ostringstream stream;
+
+            Separator separator( ", ", numVals );
+
+            typename OutputTrait< TYPE >::output_type min
+                = std::numeric_limits< typename OutputTrait< TYPE >::output_type >::max();
+
+            typename OutputTrait< TYPE >::output_type max
+                = std::numeric_limits< typename OutputTrait< TYPE >::output_type >::min();
+
+            stream << "{" << std::endl;
+            stream << "    \"values\" : [ ";
+
+            for ( size_t i = 0; i < numVals; ++i )
+            {
+                stream << typename OutputTrait< TYPE >::output_type( data[ i ] ) << separator;
+
+                min = std::min(
+                        typename OutputTrait< TYPE >::output_type( data[ i ] ),
+                        min 
+                        );
+
+                max = std::max(
+                        typename OutputTrait< TYPE >::output_type( data[ i ] ),
+                        max 
+                        );
+            }
+
+            stream << " ]," << std::endl;
+
+            stream << " \"max\" : " << max << "," << std::endl;
+            stream << " \"min\" : " << min << std::endl;
+
+            stream << "}" << std::endl;
+
+            sprintf( buf, "%s", stream.str().c_str() );
+
+            return stream.str().size();
+        }
+    };
+
+    int handleProperty( PropertyData& propertyData, char* buf )
+    {
+        PropertyHandler< JsonValuesScalarOp, JsonValuesArrayOp > propertyHandler;
+
+        return propertyHandler.handle( propertyData, buf );
+    }
+
+private:
+
+};
+
+#endif // ALEMBICFS_VALUESPROPERTYVIEW_HH
+
+

src/main.cc

@@ -2,6 +2,7 @@
 #include "AlembicFS.hh"
 #include "wrap.hh"
 
+#include "JsonValuesPropertyView.hh"
 #include "MaxValuePropertyView.hh"
 #include "MinValuePropertyView.hh"
 #include "ValuesPropertyView.hh"
@@ -75,6 +76,9 @@ int main(int argc, char *argv[])
     boost::scoped_ptr< PropertyView > maxValuePropertyView( new MaxValuePropertyView );
     propertyViewLookup[ "max" ] = maxValuePropertyView.get();
 
+    boost::scoped_ptr< PropertyView > jsonValuesPropertyView( new JsonValuesPropertyView );
+    propertyViewLookup[ "json" ] = jsonValuesPropertyView.get();
+
     boost::scoped_ptr< AlembicFS > instance(
             new AlembicFS(
                 "/",        // Set our root - is this needed?