private static List <byte[]> ExtractBuffers(glTFLoader.Schema.Gltf model, string baseDir)
{
var buffers = new List <byte[]>();
foreach (var selectedBuffer in model.Buffers)
{
if (selectedBuffer.Uri.StartsWith("data:") && DataURL.FromUri(selectedBuffer.Uri, out DataURL output))
{
if (output.Data.Length != selectedBuffer.ByteLength)
{
throw new InvalidDataException(
string.Format(
"The specified length of embedded data chunk ({0}) is not equal to the actual length of the data chunk ({1}).",
selectedBuffer.ByteLength,
output.Data.Length)
);
}
buffers.Add(output.Data);
}
else
{
// OPEN FILE
string additionalFilePath = System.IO.Path.Combine(baseDir, selectedBuffer.Uri);
using (var fs = File.Open(additionalFilePath, FileMode.Open))
using (var br = new BinaryReader(fs))
{
// ONLY READ SPECIFIED CHUNK SIZE
buffers.Add(br.ReadBytes(selectedBuffer.ByteLength));
}
}
}
return(buffers);
}
private static MgtfBuffer[] ExtractBuffers(string baseDir, glTFLoader.Schema.Buffer[] buffers)
{
var result = new List <MgtfBuffer>();
foreach (var selectedBuffer in buffers)
{
if (selectedBuffer.Uri.StartsWith("data:") && DataURL.FromUri(selectedBuffer.Uri, out DataURL output))
{
if (output.Data.Length != selectedBuffer.ByteLength)
{
throw new InvalidDataException(
string.Format(
"The specified length of embedded data chunk ({0}) is not equal to the actual length of the data chunk ({1}).",
selectedBuffer.ByteLength,
output.Data.Length)
);
}
result.Add(
new MgtfBuffer {
Data = output.Data,
}
);
}
else
{
// OPEN FILE
string additionalFilePath = System.IO.Path.Combine(baseDir, selectedBuffer.Uri);
using (var fs = File.Open(additionalFilePath, FileMode.Open))
using (var br = new BinaryReader(fs))
{
// ONLY READ SPECIFIED CHUNK SIZE
result.Add(
new MgtfBuffer
{
Data = br.ReadBytes(selectedBuffer.ByteLength)
}
);
}
}
}
return(result.ToArray());
}
private MgtfImage[] ExtractImages(string baseDir, Image[] images, BufferView[] bufferViews)
{
var count = images != null ? images.Length : 0;
var output = new MgtfImage[count];
for (var i = 0; i < count; i += 1)
{
var current = images[i];
byte[] src = null;
ulong srcOffset = 0;
ulong srcLength = 0UL;
int? bufferRef = null;
string userDefMimeType = null;
if (current.BufferView.HasValue)
{
var view = bufferViews[current.BufferView.Value];
src = null;
bufferRef = view.Buffer;
srcOffset = (ulong)view.ByteOffset;
srcLength = (ulong)view.ByteLength;
}
else if (!string.IsNullOrWhiteSpace(current.Uri))
{
if (DataURL.FromUri(current.Uri, out DataURL urlData))
{
userDefMimeType = urlData.MediaType;
src = urlData.Data;
srcOffset = 0UL;
srcLength = (ulong)urlData.Data.Length;
}
else
{
// OPEN FILE
userDefMimeType = Path.GetExtension(current.Uri).ToUpperInvariant();
string additionalFilePath = System.IO.Path.Combine(baseDir, current.Uri);
using (var fs = File.Open(additionalFilePath, FileMode.Open))
using (var ms = new MemoryStream())
{
fs.CopyTo(ms);
src = ms.ToArray();
srcOffset = 0UL;
srcLength = (ulong)src.Length;
}
}
}
MgtfImageMimeType mimeType =
current.MimeType.HasValue
? GetImageTypeFromJSON(current.MimeType.Value)
: GetImageTypeFromStr(userDefMimeType);
var temp = new MgtfImage
{
Name = current.Name,
MimeType = mimeType,
Source = src,
Buffer = bufferRef,
SrcOffset = srcOffset,
SrcLength = srcLength,
};
output[i] = temp;
}
return(output);
}
public static bool FromUri(string uri, out DataURL output)
{
// https://tools.ietf.org/html/rfc2397
// BASE64
// data:[< mediatype >][; base64],< data >
//
// dataurl:= "data:"[mediatype][";base64"] "," data
// mediatype := [type "/" subtype] * (";" parameter )
// data:= *urlchar
// parameter:= attribute "=" value
const string DATA_PREFIX = "data:";
if (!uri.StartsWith(DATA_PREFIX))
{
output = null;
return(false);
}
var endOfPrefix = uri.IndexOf(',');
if (endOfPrefix <= -1)
{
output = null;
return(false);
}
// DON'T include the comma on end
var mediaTypeToken = uri.Substring(DATA_PREFIX.Length, endOfPrefix - DATA_PREFIX.Length);
var parameters = mediaTypeToken.Split(new char[] { ';' }, StringSplitOptions.None);
const string PLAIN_TEXT = "text/plain";
var mediaType = (parameters.Length > 0 && string.IsNullOrEmpty(parameters[0]))
? PLAIN_TEXT
: parameters[0];
const string BASE_64_FLAG = "base64";
var useBase64 = (parameters.Length > 0 && parameters[parameters.Length - 1] == BASE_64_FLAG);
// LOOK FOR CHARSET
string textCharsetString = "US-ASCII";
const string CHARSET_TOKEN = "charset";
for (var i = 1; i < parameters.Length; i += 1)
{
if (parameters[i].Contains("="))
{
var paramTokens = parameters[i].Split(new[] { '=' }, StringSplitOptions.None);
if (paramTokens.Length == 2 && paramTokens[0] == CHARSET_TOKEN)
{
textCharsetString = paramTokens[1];
}
}
}
// DEFAULT is text/plain;charset=US-ASCII
var dataToken = uri.Substring(endOfPrefix + 1);
if (useBase64)
{
output = new DataURL
{
MediaType = mediaType,
CharSet = textCharsetString,
Data = Convert.FromBase64String(dataToken),
};
return(true);
}
else
{
var encoder = Encoding.GetEncoding(textCharsetString);
output = new DataURL
{
MediaType = mediaType,
CharSet = textCharsetString,
Data = encoder.GetBytes(dataToken),
};
return(true);
}
}
