Move obj reader and obj material reader commands to separate classes …

…and functions

src/ThreeDModels/Format/Obj/IO/Commands/DisplayAttributes/BevelCommand.cs

@@ -0,0 +1,19 @@
+using ThreeDModels.Format.Obj.Display;
+
+namespace ThreeDModels.Format.Obj.IO.Commands.DisplayAttributes;
+
+internal class BevelCommand : ICommand
+{
+    public static string Name => "bevel";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        context.Display ??= new Display.DisplayAttributes();
+        context.Display.BevelInterpolationEnabled = ObjReader.GetBool(commandLine[1]);
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/DisplayAttributes/ColorInterpolationCommand.cs

@@ -0,0 +1,17 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.DisplayAttributes;
+
+internal class ColorInterpolationCommand : ICommand
+{
+    public static string Name => "c_interp";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        context.Display ??= new Display.DisplayAttributes();
+        context.Display.ColorInterpolationEnabled = ObjReader.GetBool(commandLine[1]);
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/DisplayAttributes/DissolveInterpolationCommand.cs

@@ -0,0 +1,17 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.DisplayAttributes;
+
+internal class DissolveInterpolationCommand : ICommand
+{
+    public static string Name => "d_interp";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        context.Display ??= new Display.DisplayAttributes();
+        context.Display.DissolveInterpolationEnabled = ObjReader.GetBool(commandLine[1]);
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/DisplayAttributes/LevelOfDetailCommand.cs

@@ -0,0 +1,17 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.DisplayAttributes;
+
+internal class LevelOfDetailCommand : ICommand
+{
+    public static string Name => "lod";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        context.Display ??= new Display.DisplayAttributes();
+        context.Display.LevelOfDetail = int.Parse(commandLine[1]);
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/DisplayAttributes/MaterialLibraryCommand.cs

@@ -0,0 +1,66 @@
+using ThreeDModels.Format.Obj.Display;
+using ThreeDModels.Format.Obj.IO.Commands.Materials;
+
+namespace ThreeDModels.Format.Obj.IO.Commands.DisplayAttributes;
+
+internal class MaterialLibraryCommand : ICommand
+{
+    private static readonly Dictionary<string, IMaterialCommandRead> _commands = new()
+    {
+        { NewMaterialCommand.Name, NewMaterialCommand.Read },
+        { AmbientColorCommand.Name, AmbientColorCommand.Read },
+        { DiffuseColorCommand.Name, DiffuseColorCommand.Read },
+        { SpecularColorCommand.Name, SpecularColorCommand.Read },
+        { SpecularExponentCommand.Name, SpecularExponentCommand.Read },
+        { DissolveCommand.Name, DissolveCommand.Read },
+        { TransparencyCommand.Name, TransparencyCommand.Read },
+        { IlluminationModelCommand.Name, IlluminationModelCommand.Read },
+    };
+    public static string Name => "mtllib";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        for (int i = 1; i < commandLine.Count; i++)
+        {
+            obj.MaterialLibraries.Add(GetMaterials(commandLine[i]));
+        }
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+
+    private static List<Material> GetMaterials(string path)
+    {
+        using var fs = new FileStream(path, FileMode.Open, FileAccess.Read);
+        return GetMaterials(fs);
+    }
+
+    private static List<Material> GetMaterials(Stream stream)
+    {
+        var context = new MaterialReaderContext(material: null, materials: []);
+        using var textReader = new StreamReader(stream);
+        while (stream.Position < stream.Length)
+        {
+            var commandLine = ObjReader.GetCommandLine(textReader);
+            if (commandLine.Count == 0)
+            {
+                continue;
+            }
+            if (_commands.TryGetValue(commandLine[0], out var readCommand))
+            {
+                readCommand.Invoke(commandLine, context);
+            }
+            else
+            {
+                throw new InvalidDataException($"Unknown material command '{commandLine[0]}'");
+            }
+        }
+        if (context.Material != null)
+        {
+            context.Materials.Add(context.Material);
+        }
+        return context.Materials;
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/DisplayAttributes/UseMapCommand.cs

@@ -0,0 +1,17 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.DisplayAttributes;
+
+internal class UseMapCommand : ICommand
+{
+    public static string Name => "usemap";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        context.Display ??= new Display.DisplayAttributes();
+        context.Display.TextureMapName = commandLine.Count > 1 && commandLine[1] != Constants.Off ? commandLine[1] : string.Empty;
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/DisplayAttributes/UseMaterialCommand.cs

@@ -0,0 +1,17 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.DisplayAttributes;
+
+internal class UseMaterialCommand : ICommand
+{
+    public static string Name => "usemtl";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        context.Display ??= new Display.DisplayAttributes();
+        context.Display.MaterialName = commandLine.Count > 1 ? commandLine[1] : string.Empty;
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/FreeFormCurveSurfaceAttributes/BasisMatrixCommand.cs

@@ -0,0 +1,34 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.FreeFormCurveSurfaceAttributes;
+
+internal class BasisMatrixCommand : ICommand
+{
+    public static string Name => "bmat";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        if (context.FreeFormGeometry == null)
+        {
+            throw new InvalidDataException("BasisMatrix (bmat) must follow a curve or surface element");
+        }
+        var matrix = new List<float>();
+        for (int i = 2; i < commandLine.Count; i++)
+        {
+            matrix.Add(float.Parse(commandLine[i]));
+        }
+        if (commandLine[1] == "u")
+        {
+            context.FreeFormGeometry.BasisMatrixU = matrix;
+        }
+        else
+        {
+            context.FreeFormGeometry.BasisMatrixV = commandLine[1] == "v"
+                ? matrix
+                : throw new InvalidDataException($"BasisMatrix (bmat) has an invalid direction '{commandLine[1]}'");
+        }
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/FreeFormCurveSurfaceAttributes/CurveSurfaceTypeCommand.cs

@@ -0,0 +1,30 @@
+using ThreeDModels.Format.Obj.Elements;
+
+namespace ThreeDModels.Format.Obj.IO.Commands.FreeFormCurveSurfaceAttributes;
+
+internal class CurveSurfaceTypeCommand : ICommand
+{
+    public static string Name => "cstype";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        if (context.FreeFormGeometry == null)
+        {
+            throw new InvalidDataException("CurveSurfaceType (cstype) must follow a curve or surface element");
+        }
+        if (commandLine.Count > 2)
+        {
+            context.FreeFormGeometry.IsRational = commandLine[1] == "rat";
+            context.FreeFormGeometry.Type = Enum.Parse<CurveSurfaceType>(commandLine[2]);
+        }
+        else
+        {
+            context.FreeFormGeometry.Type = Enum.Parse<CurveSurfaceType>(commandLine[1]);
+        }
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/FreeFormCurveSurfaceAttributes/DegreeCommand.cs

@@ -0,0 +1,21 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.FreeFormCurveSurfaceAttributes;
+
+internal class DegreeCommand : ICommand
+{
+    public static string Name => "deg";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        if (context.FreeFormGeometry == null)
+        {
+            throw new InvalidDataException("Degree (deg) must follow a curve or surface element");
+        }
+        context.FreeFormGeometry.DegreeU = int.Parse(commandLine[1]);
+        context.FreeFormGeometry.DegreeV = commandLine.Count > 2 ? int.Parse(commandLine[2]) : null;
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/FreeFormCurveSurfaceAttributes/StepCommand.cs

@@ -0,0 +1,21 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.FreeFormCurveSurfaceAttributes;
+
+internal class StepCommand : ICommand
+{
+    public static string Name => "step";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        if (context.FreeFormGeometry == null)
+        {
+            throw new InvalidDataException("Step (step) must follow a curve or surface element");
+        }
+        context.FreeFormGeometry.StepU = int.Parse(commandLine[1]);
+        context.FreeFormGeometry.StepV = commandLine.Count > 2 ? int.Parse(commandLine[2]) : null;
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/FreeFormCurveSurfaceBodyStatements/EndFreeFormGeometryCommand.cs

@@ -0,0 +1,38 @@
+using ThreeDModels.Format.Obj.Elements;
+
+namespace ThreeDModels.Format.Obj.IO.Commands.FreeFormCurveSurfaceBodyStatements;
+
+internal class EndFreeFormGeometryCommand : ICommand
+{
+    public static string Name => "end";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        if (context.FreeFormGeometry == null)
+        {
+            throw new InvalidDataException("The curve or surface element is not initialized");
+        }
+        else if (context.FreeFormGeometry is Curve curve)
+        {
+            context.Group.Curves.Add(curve);
+        }
+        else if (context.FreeFormGeometry is Curve2D curve2D)
+        {
+            context.Group.Curves2D.Add(curve2D);
+        }
+        else if (context.FreeFormGeometry is Surface surface)
+        {
+            context.Group.Surfaces.Add(surface);
+        }
+        else
+        {
+            throw new InvalidDataException("Unknown free-form geometry type");
+        }
+        context.FreeFormGeometry = null;
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/FreeFormCurveSurfaceBodyStatements/HoleCommand.cs

@@ -0,0 +1,33 @@
+using ThreeDModels.Format.Obj.Elements;
+
+namespace ThreeDModels.Format.Obj.IO.Commands.FreeFormCurveSurfaceBodyStatements;
+
+internal class HoleCommand : ICommand
+{
+    public static string Name => "hole";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        if (context.FreeFormGeometry == null)
+        {
+            throw new InvalidDataException("Hole (hole) must follow a curve or surface element");
+        }
+        var curve2Ds = new List<Curve2DReference>();
+        for (int i = 1; i < commandLine.Count; i += 3)
+        {
+            curve2Ds.Add(new()
+            {
+                Start = float.Parse(commandLine[i]),
+                End = float.Parse(commandLine[i + 1]),
+                Curve2DIndex = int.Parse(commandLine[i + 2]),
+            });
+        }
+        context.FreeFormGeometry.Holes ??= [];
+        context.FreeFormGeometry.Holes.Add(curve2Ds);
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}

src/ThreeDModels/Format/Obj/IO/Commands/FreeFormCurveSurfaceBodyStatements/ParameterCommand.cs

@@ -0,0 +1,34 @@
+namespace ThreeDModels.Format.Obj.IO.Commands.FreeFormCurveSurfaceBodyStatements;
+
+internal class ParameterCommand : ICommand
+{
+    public static string Name => "parm";
+
+    public static void Read(List<string> commandLine, ObjReaderContext context, ref Obj obj)
+    {
+        if (context.FreeFormGeometry == null)
+        {
+            throw new InvalidDataException("Parameter (parm) must follow a curve or surface element");
+        }
+        var matrix = new List<float>();
+        for (int i = 2; i < commandLine.Count; i++)
+        {
+            matrix.Add(float.Parse(commandLine[i]));
+        }
+        if (commandLine[1] == "u")
+        {
+            context.FreeFormGeometry.ParameterU = matrix;
+        }
+        else
+        {
+            context.FreeFormGeometry.ParameterV = commandLine[1] == "v"
+                ? matrix
+                : throw new InvalidDataException($"BasisMatrix (bmat) has an invalid direction '{commandLine[1]}'");
+        }
+    }
+
+    public static void Write()
+    {
+        throw new NotImplementedException();
+    }
+}