Add mechanical entities and proxy graphics

src/ACadSharp/Entities/Mechanical/AcmBalloon.cs

@@ -0,0 +1,18 @@
+using CSMath;
+
+namespace ACadSharp.Entities.Mechanical;
+
+public class AcmBalloon : ProxyDataEntity
+{
+	public override ObjectType ObjectType { get { return ObjectType.UNLISTED; } }
+
+	public override void ApplyTransform(Transform transform)
+	{
+		throw new System.NotImplementedException();
+	}
+
+	public override BoundingBox GetBoundingBox()
+	{
+		throw new System.NotImplementedException();
+	}
+}

src/ACadSharp/Entities/Mechanical/AcmPartList.cs

@@ -0,0 +1,18 @@
+using CSMath;
+
+namespace ACadSharp.Entities.Mechanical;
+
+public class AcmPartList : ProxyDataEntity
+{
+	public override ObjectType ObjectType { get { return ObjectType.UNLISTED; } }
+
+	public override void ApplyTransform(Transform transform)
+	{
+		throw new System.NotImplementedException();
+	}
+
+	public override BoundingBox GetBoundingBox()
+	{
+		throw new System.NotImplementedException();
+	}
+}

src/ACadSharp/Entities/Mechanical/AcmPartRef.cs

@@ -0,0 +1,22 @@
+using CSMath;
+
+namespace ACadSharp.Entities.Mechanical;
+
+public class AcmPartRef : ProxyDataEntity
+{
+	public override ObjectType ObjectType { get { return ObjectType.UNLISTED; } }
+
+	public XYZ Position { get; internal set; }
+
+	public double Radius { get; internal set; }
+
+	public override void ApplyTransform(Transform transform)
+	{
+		throw new System.NotImplementedException();
+	}
+
+	public override BoundingBox GetBoundingBox()
+	{
+		throw new System.NotImplementedException();
+	}
+}

src/ACadSharp/Entities/Mechanical/ProxyDataEntity.cs

@@ -0,0 +1,8 @@
+using ACadSharp.Entities.ProxyGraphics;
+
+namespace ACadSharp.Entities.Mechanical;
+
+public abstract class ProxyDataEntity : Entity
+{
+	public IProxyGraphic[] ProxyGraphics { get; set; }
+}

src/ACadSharp/Entities/ProxyEntity.cs

@@ -64,6 +64,7 @@ public class ProxyEntity : Entity, IProxy
 		//An object ID(multiple entries can appear) (optional)
 
 		//94 0 (indicates end of object ID section)
+
 		/// <inheritdoc/>
 		public ACadVersion Version { get; set; }
 

src/ACadSharp/Entities/ProxyGraphics/GraphicsType.cs

@@ -0,0 +1,41 @@
+namespace ACadSharp.Entities.ProxyGraphics;
+
+public enum GraphicsType
+{
+	Unknown = 0,
+	Extents = 1,
+	Circle = 2,
+	CirclePt3 = 3,
+	CircularArc = 4,
+	CircularArc3Pt = 5,
+	Polyline = 6,
+	Polygon = 7,
+	Mesh = 8,
+	Shell = 9,
+	Text = 10,
+	Text2 = 11,
+	XLine = 12,
+	Ray = 13,
+	SubentColor = 14,
+	SubentLayer = 16,
+	SubentLineType = 18,
+	SubentMarker = 19,
+	SubentFillon = 20,
+	SubentTrueColor = 22,
+	SubentLineWeight = 23,
+	SubentLineTypeScale = 24,
+	SubentThickness = 25,
+	SubentPlotStyleName = 26,
+	PushClip = 27,
+	PopClip = 28,
+	PushModelTransform = 29,
+	PushModelTransform2 = 30,
+	PophModelTransform = 31,
+	PolylineWithNormal = 32,
+	LwPolyine = 33,
+	SubEntityMaterial = 34,
+	SubEntityMapper = 35,
+	UnicodeText = 36,
+	Unknown37 = 37,
+	UnicodeText2 = 38,//No code specified
+}

src/ACadSharp/Entities/ProxyGraphics/IProxyGraphic.cs

@@ -0,0 +1,5 @@
+namespace ACadSharp.Entities.ProxyGraphics;
+
+public interface IProxyGraphic;
+
+public class ProxyEntityUnsupported : IProxyGraphic;

src/ACadSharp/Entities/ProxyGraphics/ProxyCircle.cs

@@ -0,0 +1,10 @@
+using CSMath;
+
+namespace ACadSharp.Entities.ProxyGraphics;
+
+public class ProxyCircle : IProxyGraphic
+{
+	public XYZ Center { get; set; }
+	public double Radius { get; set; }
+	public XYZ Normal { get; set; }
+}

src/ACadSharp/Entities/ProxyGraphics/ProxyPolyline.cs

@@ -0,0 +1,8 @@
+using CSMath;
+
+namespace ACadSharp.Entities.ProxyGraphics;
+
+public class ProxyPolyline : IProxyGraphic
+{
+	public XYZ[] Points { get; set; }
+}

src/ACadSharp/Entities/ProxyGraphics/ProxyPushModelTransform.cs

@@ -0,0 +1,8 @@
+using CSMath;
+
+namespace ACadSharp.Entities.ProxyGraphics;
+
+public class ProxyPushModelTransform : IProxyGraphic
+{
+	public Matrix4 TransformationMatrix { get; set; }
+}

src/ACadSharp/Entities/ProxyGraphics/ProxyText.cs

@@ -0,0 +1,46 @@
+using CSMath;
+
+namespace ACadSharp.Entities.ProxyGraphics;
+
+public class ProxyText : IProxyGraphic
+{
+	public XYZ StartPoint { get; set; }
+	public XYZ Normal { get; set; }
+	public XYZ TextDirection { get; set; }
+	public string Text { get; set; }
+
+	/// <summary>
+	/// The length of the text in characters, or -1 if the text is zero terminated
+	/// </summary>
+	public int TextLength { get; set; }	// The text length is often != -1 even if the string is zero terminated?
+
+	/// <summary>
+	/// If <see langword="true"/>, special patterns e.g. %% are not supposed to be interpreted
+	/// </summary>
+	public bool IsRaw { get; set; }
+	public double Height { get; set; }
+	public double WidthFactor { get; set; }
+	public double ObliqueAngle { get; set; }
+	public double TrackingPercentage { get; set; }
+
+	public bool IsBackwards { get; set; }
+	public bool IsUpsideDown { get; set; }
+	public bool IsVertical { get; set; }
+	public bool IsUnderlined { get; set; }
+	public bool IsOverlined { get; set; }
+
+	public TrueTypeFontDescriptor FontDescriptor { get; set; }
+
+	public string BigFontFilename { get; set; }
+}
+
+public class TrueTypeFontDescriptor
+{
+	public bool IsBold { get; set; }
+	public bool IsItalic { get; set; }
+	public byte Charset { get; set; }
+	public byte PitchAndFamily { get; set; }
+
+	public string Typeface { get; set; }
+	public string FontFilename { get; set; }
+}

src/ACadSharp/IO/DWG/DwgStreamReaders/DwgMergedReader.cs

@@ -333,6 +333,15 @@ public string ReadVariableText()
 			return this._textReader.ReadVariableText();
 		}
 
+		public string ReadPaddedUnicodeString()
+		{
+			//Handle the text section if is empty
+			if (this._textReader.IsEmpty)
+				return string.Empty;
+
+			return this._textReader.ReadVariableText();
+		}
+
 		public ushort ResetShift()
 		{
 			return this._mainReader.ResetShift();