Beatmup::Python::WritableChunkCollection Class Reference

Writable ChunkCollection implementation for Python. More...

#include <chunk_collection.h>

Inheritance diagram for Beatmup::Python::WritableChunkCollection:

Public Member Functions
	WritableChunkCollection ()
pybind11::buffer &	operator[] (const std::string &id)
void	open ()
	Opens the collection to read chunks from it. More...
void	close ()
	Closes the collection after a reading session. More...
size_t	size () const
	Returns the number of chunks available in the collection after it is opened. More...
bool	chunkExists (const std::string &id) const
	Check if a specific chunk exists. More...
chunksize_t	chunkSize (const std::string &id) const
	Retrieves size of a specific chunk. More...
chunksize_t	fetch (const std::string &id, void *data, const chunksize_t limit)
	Reads a chunk. More...
void	save (const std::string &filename, bool append=false)
	Saves the collection to a file. More...
Public Member Functions inherited from Beatmup::ChunkCollection
template<typename datatype >
datatype	read (const std::string &id)
	Reads a chunk and casts it into a given type. More...
template<typename datatype >
std::vector< datatype >	readVector (const std::string &id)
	Reads a chunk into a vector of a specific type. More...
template<>
std::string	read (const std::string &id)
Public Member Functions inherited from Beatmup::Object
virtual	~Object ()

Private Attributes
std::map< std::string, pybind11::buffer >	data

Detailed Description

Writable ChunkCollection implementation for Python.

Allows to exchange binary data without copying.

Definition at line 35 of file chunk_collection.h.

Constructor & Destructor Documentation

WritableChunkCollection()

Beatmup::Python::WritableChunkCollection::WritableChunkCollection ( )

inline

Definition at line 40 of file chunk_collection.h.

{}

Member Function Documentation

operator[]()

pybind11::buffer& Beatmup::Python::WritableChunkCollection::operator[] ( const std::string &  id )

inline

Definition at line 42 of file chunk_collection.h.

                                                                   {
                return data[id];
            }

open()

void Beatmup::Python::WritableChunkCollection::open ( )

inlinevirtual

Opens the collection to read chunks from it.

Implements Beatmup::ChunkCollection.

Definition at line 46 of file chunk_collection.h.

{}

close()

void Beatmup::Python::WritableChunkCollection::close ( )

inlinevirtual

Closes the collection after a reading session.

Implements Beatmup::ChunkCollection.

Definition at line 47 of file chunk_collection.h.

{}

size()

size_t Beatmup::Python::WritableChunkCollection::size ( ) const

inlinevirtual

Returns the number of chunks available in the collection after it is opened.

Implements Beatmup::ChunkCollection.

Definition at line 49 of file chunk_collection.h.

{ return data.size(); }

chunkExists()

bool Beatmup::Python::WritableChunkCollection::chunkExists ( const std::string &  id ) const

inlinevirtual

Check if a specific chunk exists.

Parameters

[in]

id

The chunk id

Returns

true if the chunk exists in the collection.

Implements Beatmup::ChunkCollection.

Definition at line 51 of file chunk_collection.h.

{ return data.find(id) != data.cend(); }

chunkSize()

chunksize_t Python::WritableChunkCollection::chunkSize ( const std::string &  id ) const

virtual

Retrieves size of a specific chunk.

Parameters

[in]

id

The chunk id

Returns

size of the chunk in bytes, 0 if not found.

Implements Beatmup::ChunkCollection.

Definition at line 104 of file chunk_collection.cpp.

                                                                              {
    auto it = data.find(id);
    if (it == data.cend())
        return 0;
    auto info = it->second.request();
    return info.size * info.itemsize;
}

fetch()

chunksize_t Python::WritableChunkCollection::fetch ( const std::string &  id, void *  data, const chunksize_t  limit  )

virtual

Reads a chunk.

The collection is expected to be opened.

Parameters

[in]	id	Wanted chunk id.
[out]	data	A buffer to write out the wanted chunk content.
[in]	limit	The buffer capacity in bytes.

Returns

number of bytes written out to the buffer: if the chunk is found fits the buffer, the chunk size is returned; if the chunk is found and too big, limit is returned (number of bytes actually written); if no chunk found, 0 is returned.

Implements Beatmup::ChunkCollection.

Definition at line 113 of file chunk_collection.cpp.

                                                                                                         {
    auto it = this->data.find(id);
    if (it == this->data.end())
        return 0;
    Internal::Copy copy(it->second.request(), data, limit);
    return limit - copy.remaining();
}

save()

void Python::WritableChunkCollection::save ( const std::string &  filename, bool  append = false  )

virtual

Saves the collection to a file.

Parameters

[in]	filename	The name of the file to write chunks to
[in]	append	If true, writing to the end of the file (keeping the existing content). Rewriting the file otherwise.

Implements Beatmup::ChunkCollection.

Definition at line 122 of file chunk_collection.cpp.

                                                                               {
    ChunkFileWriter writer(filename, append);
    for (auto it : data) {
        Chunk chunk(*this, it.first);
        writer(it.first, chunk(), chunk.size());
    }
}

Member Data Documentation

data

std::map<std::string, pybind11::buffer> Beatmup::Python::WritableChunkCollection::data

private

Definition at line 37 of file chunk_collection.h.

---

The documentation for this class was generated from the following files:

• python/src/chunk_collection.h
• python/src/chunk_collection.cpp