DataViewStructure

DataViewStructure is a class that allows reading and writing structured data to a DataView.

The struct definition looks like this:

{
  fileSignature: 'fourCC'
  numTable: 'uint16'
  value1: 'int32'
  value2: 'int32'
}

You can add types to the DataViewStructure.types object.

Example

const littleEndian=false;
const struct=new DataViewStructure({
  sfntVersion:   'fourcc', 
  numTables:     'uint16',
  searchRange:   'uint16',
  entrySelector: 'uint16',
  rangeShift:    'uint16' 
},littleEndian);

const dv=new DataView(new ArryaBuffer(1024));
struct.read(dv,0); // read headers
struct.set('numTables',struct.get('numTables')+1); // manipulate data DataViewStructure extends the Map object
struct.write(dv,0); // writes the changes back to the ArrayBuffer
// (you're then supposed to write the ArrayBuffer back to a file)

TODO

• As of right now there are not enough types to even cover all of DataView basic capabilities. i.e. no floats. I implemented this only to parse ttf and otf metadata.
  More grunt work on that font is needed.
• A cstring and a pascalstring type will be added, though size computation will be an issue.