static Mesh3D ParseSTLASCII(ModelFileData fileData)
{
// STL ASCII Format: https://en.wikipedia.org/wiki/STL_(file_format)#Binary_STL
if (!fileData.HasBytes())
{
return(null);
}
List <Mesh3D.Vertexh> vertices = new List <Mesh3D.Vertexh>();
try
{
Stream fileDataStream = fileData.GetStream();
fileDataStream.Position = 0;
StreamReader reader = new StreamReader(fileDataStream);
while (!reader.EndOfStream)
{
string line = reader.ReadLine().TrimStart();
if (!line.StartsWith("vertex"))
{
continue;
}
for (int i = 0; i < 3; i++)
{
var matches = Regex.Matches(line, FloatStringPattern);
vertices.Add(new Mesh3D.Vertexh(
Half.Parse(matches[0].Value),
Half.Parse(matches[1].Value),
Half.Parse(matches[2].Value)
));
line = reader.ReadLine().TrimStart();
}
}
}
catch (Exception ex)
{
logger.Trace(ex, "Exception when processing file: {FileName}, {FileSizeKB}, {FileType}", fileData.FileName, fileData.FileSizeKB, fileData.FileType.ToString());
return(null);
}
SegmentedArray <Mesh3D.Vertexh> verticesArray = new SegmentedArray <Mesh3D.Vertexh>(vertices.Count);
SegmentedArray <int> trianglesArray = new SegmentedArray <int>(vertices.Count);
for (int i = 0; i < vertices.Count; i++)
{
verticesArray[i] = vertices[i];
trianglesArray[i] = i;
}
return(new Mesh3D(verticesArray, trianglesArray));
}
static Mesh3D ParseWavefront(ModelFileData fileData)
{
// Wavefront OBJ Format: https://en.wikipedia.org/wiki/Wavefront_.obj_file
if (!fileData.HasBytes())
{
return(null);
}
List <Mesh3D.Vertexh> vertices = new List <Mesh3D.Vertexh>();
List <int> triangles = new List <int>();
try
{
Stream fileDataStream = fileData.GetStream();
fileDataStream.Position = 0;
StreamReader reader = new StreamReader(fileDataStream);
while (!reader.EndOfStream)
{
string line = reader.ReadLine().TrimStart();
if (string.IsNullOrWhiteSpace(line))
{
continue;
}
if (line.StartsWith("v "))
{
var matches = Regex.Matches(line, FloatStringPattern);
if (matches.Count >= 6)
{ // Dodge the vertex color (or is it supposed to come after x y z? Wikipedia is not clear about it).
vertices.Add(new Mesh3D.Vertexh(
Half.Parse(matches[0].Value),
Half.Parse(matches[2].Value),
Half.Parse(matches[4].Value)
));
}
else
{
vertices.Add(new Mesh3D.Vertexh(
Half.Parse(matches[0].Value),
Half.Parse(matches[1].Value),
Half.Parse(matches[2].Value)
));
}
}
else if (line.StartsWith("f"))
{
IEnumerable <string> faceIndexes = line.Split(' ').Where(s => s != "f" && !string.IsNullOrWhiteSpace(s));
int index0 = triangles.Count; // First index added for this line.
for (int i = 0; i < faceIndexes.Count(); i++)
{
int.TryParse(faceIndexes.ElementAt(i).Split('/').First(), out int parsedIndex);
// Handle the face as a triangle fan to support faces with more than 3 vertex (idea from https://notes.underscorediscovery.com/obj-parser-easy-parse-time-triangulation/).
if (i >= 3)
{
triangles.Add(triangles[index0]);
triangles.Add(triangles[triangles.Count - 2]);
}
triangles.Add(parsedIndex - 1); // -1 because our array starts at 0 while the OBJ starts at 1.
}
}
else
{
continue;
}
}
}
catch (Exception ex)
{
logger.Trace(ex, "Exception when processing file: {FileName}, {FileSizeKB}, {FileType}", fileData.FileName, fileData.FileSizeKB, fileData.FileType.ToString());
return(null);
}
SegmentedArray <Mesh3D.Vertexh> verticesArray = new SegmentedArray <Mesh3D.Vertexh>(vertices.Count);
SegmentedArray <int> trianglesArray = new SegmentedArray <int>(triangles.Count);
for (int i = 0; i < vertices.Count; i++)
{
verticesArray[i] = vertices[i];
}
for (int i = 0; i < triangles.Count; i++)
{
trianglesArray[i] = triangles[i];
}
return(new Mesh3D(verticesArray, trianglesArray));
}
