public static ColrTable Load(BigEndianBinaryReader reader)
{
// HEADER
// Type | Name | Description
// ----------|------------------------|----------------------------------------------------------------------------------------------------
// uint16 | version | Table version number(starts at 0).
// uint16 | numBaseGlyphRecords | Number of Base Glyph Records.
// Offset32 | baseGlyphRecordsOffset | Offset(from beginning of COLR table) to Base Glyph records.
// Offset32 | layerRecordsOffset | Offset(from beginning of COLR table) to Layer Records.
// uint16 | numLayerRecords | Number of Layer Records.
// Base Glyph Record
// Type | Name | Description
// ----------|------------------------|----------------------------------------------------------------------------------------------------
// uint16 | gID | Glyph ID of reference glyph. This glyph is for reference only and is not rendered for color.
// uint16 | firstLayerIndex | Index(from beginning of the Layer Records) to the layer record. There will be numLayers consecutive entries for this base glyph.
// uint16 | numLayers | Number of color layers associated with this glyph.
// Layer Record
// Type | Name | Description
// ----------|------------------------|----------------------------------------------------------------------------------------------------
// uint16 | gID | Glyph ID of layer glyph (must be in z-order from bottom to top).
// uint16 | paletteIndex | Index value to use with a selected color palette. This value must be less than numPaletteEntries in
// | | > the CPAL table. A palette entry index value of 0xFFFF is a special case indicating that the text
// | | > foreground color (defined by a higher-level client) should be used and shall not be treated as
// | | > actual index into CPAL ColorRecord array.
var version = reader.ReadUInt16();
var numBaseGlyphRecords = reader.ReadUInt16();
var baseGlyphRecordsOffset = reader.ReadOffset32();
var layerRecordsOffset = reader.ReadOffset32();
var numLayerRecords = reader.ReadUInt16();
reader.Seek(baseGlyphRecordsOffset, System.IO.SeekOrigin.Begin);
var glyphs = new BaseGlyphRecord[numBaseGlyphRecords];
var layers = new LayerRecord[numLayerRecords];
for (var i = 0; i < numBaseGlyphRecords; i++)
{
var gi = reader.ReadUInt16();
var idx = reader.ReadUInt16();
var num = reader.ReadUInt16();
glyphs[i] = new BaseGlyphRecord(gi, idx, num);
}
reader.Seek(layerRecordsOffset, System.IO.SeekOrigin.Begin);
for (var i = 0; i < numLayerRecords; i++)
{
var gi = reader.ReadUInt16();
var pi = reader.ReadUInt16();
layers[i] = new LayerRecord(gi, pi);
}
return(new ColrTable(glyphs, layers));
}
public override UInt64 Validate(bool simpleValidationOnly)
{
/* See comments in OTTable regarding validation completion states and flags.
* Assumed: this method does not re-do basic validations, and the completion
* state flags can be set the same as on any prior call to the method.
*/
/* Base Base class constructor ran partial validations on the table record:
* - table record tag matches type for this derived class
* - table offset and length are within file bounds
* - table record checksum == actual table checksum
*
* For simple validation, the following additional internal validation is
* required:
* - for each base glyph record: (firstLayerIndex + numLayers) is less
* than or equal to numLayerRecords
*
* Simple validation does not validate various fields that require comparison
* with other tables:
* - gIDs in all base glyph records and all layer records are valid (compare to maxp or loca)
* - paletteIndex in all layer records is valid (compare to 'CPAL')
*/
// validate layer fields in base glyph records
for (uint i = 0; i < _numBaseGlyphRecords; i++)
{
BaseGlyphRecord bgr = _baseGlyphRecords[i];
if ((bgr.FirstLayerIndex + bgr.NumLayers) > _numLayerRecords)
{
// validate within the COLR table but not external to COLR
byte bgr_val = bgr.Validate(_numLayerRecords);
if ((bgr_val & OTFile.OTRecordValidation_ExternalValidationError) != 0)
_validationStatus |= OTFile.OTFileValidation_StructureFieldsInternallyInvalid;
}
}
// layer records have no additional COLR-internal validation
// set completion state for all COLR-internal validation
_validationStatus &= ~OTFile.OTFileValidation_PartialValidation;
_validationStatus |= OTFile.OTFileValidation_InternalValidationOnly;
if (!simpleValidationOnly)
{
// TO DO: implement this!!
}
return _validationStatus;
}
