added custom attributes to svg elements, svg writing to XML is non verbose

Source/DataTypes/SvgUnit.cs

@@ -21,12 +21,12 @@ namespace Svg
         /// <summary>
         /// Gets and empty <see cref="SvgUnit"/>.
         /// </summary>
-        public static readonly SvgUnit Empty = new SvgUnit();
+        public static readonly SvgUnit Empty = new SvgUnit(SvgUnitType.User, 0);
 
         /// <summary>
         /// Gets an <see cref="SvgUnit"/> with a value of none.
         /// </summary>
-        public static readonly SvgUnit None = new SvgUnit(SvgUnitType.None,0f);
+        public static readonly SvgUnit None = new SvgUnit(SvgUnitType.None, 0f);
 
         /// <summary>
         /// Gets a value to determine whether the unit is empty.

Source/Painting/EnumConverters.cs

@@ -107,4 +107,12 @@ namespace Svg
     {
     }
 
+    public sealed class SvgStrokeLineCapConverter : EnumBaseConverter<SvgStrokeLineCap>
+    {
+    }
+
+    public sealed class SvgStrokeLineJoinConverter : EnumBaseConverter<SvgStrokeLineJoin>
+    {
+    }
+    
 }

Source/Painting/SvgStrokeLineCap.cs

 using System;
 using System.Collections.Generic;
 using System.Text;
+using System.ComponentModel;
 
 namespace Svg
 {
+    [TypeConverter(typeof(SvgStrokeLineCapConverter))]
     public enum SvgStrokeLineCap
     {
         Butt,

Source/Painting/SvgStrokeLineJoin.cs

 using System;
 using System.Collections.Generic;
 using System.Text;
+using System.ComponentModel;
 
 namespace Svg
 {
+    [TypeConverter(typeof(SvgStrokeLineJoinConverter))]
     public enum SvgStrokeLineJoin
     {
         Miter,

Source/Paths/SvgPathBuilder.cs

@@ -18,7 +18,7 @@ namespace Svg
 		}
 	}
 	
-    internal class SvgPathBuilder : TypeConverter
+    public class SvgPathBuilder : TypeConverter
     {
         /// <summary>
         /// Parses the specified string into a collection of path segments.
@@ -46,6 +46,20 @@ namespace Svg
                     isRelative = char.IsLower(command);
                     // http://www.w3.org/TR/SVG11/paths.html#PathDataGeneralInformation
 
+                    CreatePathSegment(command, segments, coords, isRelative);
+                }
+            }
+            catch (Exception exc)
+            {
+                Trace.TraceError("Error parsing path \"{0}\": {1}", path, exc.Message);
+            }
+
+            return segments;
+        }
+
+        public static void CreatePathSegment(char command, SvgPathSegmentList segments, List<float> coords, bool isRelative)
+        {
+         
                     switch (command)
                     {
                         case 'm': // relative moveto
@@ -149,14 +163,6 @@ namespace Svg
                             break;
                     }
         }
-            }
-            catch (Exception exc)
-            {
-                Trace.TraceError("Error parsing path \"{0}\": {1}", path, exc.Message);
-            }
-
-            return segments;
-        }
 
         private static PointF Reflect(PointF point, PointF mirror)
         {

Source/Svg.csproj

@@ -121,6 +121,7 @@
     <Compile Include="Filter Effects\feGaussianBlur\SvgGaussianBlur.cs" />
     <Compile Include="Filter Effects\feMerge\SvgMerge.cs" />
     <Compile Include="Painting\EnumConverters.cs" />
+    <Compile Include="SvgDefinitionDefaults.cs" />
     <Compile Include="SvgElementAttribute.cs" />
     <Compile Include="SvgRenderer.cs" />
     <Compile Include="Painting\SvgColourConverter.cs" />

Source/SvgDefinitionDefaults.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace Svg
+{
+    /// <summary>
+    /// Holds a dictionary of the default values of the SVG specification 
+    /// </summary>
+    public static class SvgDefaults
+    {
+        //internal dictionary for the defaults
+        private static readonly Dictionary<string, string> _defaults = new Dictionary<string, string>();
+
+        static SvgDefaults()
+        {
+            _defaults["viewBox"] = "0, 0, 0, 0";
+
+            _defaults["visibility"] = "visible";
+            _defaults["opacity"] = "1";
+            _defaults["clip-rule"] = "nonzero";
+
+            _defaults["transform"] = "";
+
+            _defaults["fill"] = "Black";
+            _defaults["fill-opacity"] = "1";
+            _defaults["fill-rule"] = "nonzero";
+
+            _defaults["stroke"] = "none";
+            _defaults["stroke-opacity"] = "1";
+            _defaults["stroke-width"] = "1";
+            _defaults["stroke-miterlimit"] = "4";
+            _defaults["stroke-linecap"] = "butt";
+            _defaults["stroke-linejoin"] = "miter";
+            _defaults["stroke-dasharray"] = "none";
+            _defaults["stroke-dashoffset"] = "0";
+        }
+
+        /// <summary>
+        /// Checks whether the property value is the default value of the svg definition.
+        /// </summary>
+        /// <param name="attributeName">Name of the svg attribute</param>
+        /// <param name="propertyValue">.NET value of the attribute</param>
+        public static bool IsDefault(string attributeName, string value)
+        {
+            if (_defaults.ContainsKey(attributeName))
+            {
+                if (_defaults[attributeName] == value) return true;
+                else if (attributeName == "fill") return value == "#000000";
+            }
+            return false;
+        }
+    }
+}

Source/SvgElement.cs

@@ -22,6 +22,7 @@ namespace Svg
         private SvgElementCollection _children;
         private static readonly object _loadEventKey = new object();
         private Matrix _graphicsMatrix;
+        private Dictionary<string, string> _customAttributes;
 
         /// <summary>
         /// Gets the name of the element.
@@ -137,6 +138,11 @@ namespace Svg
             }
         }
 
+        public Dictionary<string, string> CustomAttributes
+        {
+            get { return this._customAttributes; }
+        }
+
         /// <summary>
         /// Applies the required transforms to <see cref="SvgRenderer"/>.
         /// </summary>
@@ -276,12 +282,13 @@ namespace Svg
             this._children = new SvgElementCollection(this);
             this._eventHandlers = new EventHandlerList();
             this._elementName = string.Empty;
+            this._customAttributes = new Dictionary<string, string>();
         }
 
 
 		public virtual void InitialiseFromXML(XmlTextReader reader, SvgDocument document)
 		{
-			
+            throw new NotImplementedException();
 		}
 
 
@@ -343,15 +350,10 @@ namespace Svg
                     if (propertyValue != null)
                     {
                         var type = propertyValue.GetType();
-
-                        object defaultValue = null;
-                        if(type.IsValueType)
-                            defaultValue = Activator.CreateInstance(type);
-
-                        if (!propertyValue.Equals(defaultValue) || type == typeof(float) || type == typeof(bool) || type == typeof(SvgColourServer))
-                        {
                         string value = (string)attr.Property.Converter.ConvertTo(propertyValue, typeof(string));
 
+                        if (!SvgDefaults.IsDefault(attr.Attribute.Name, value))
+                        {
 							writer.WriteAttributeString(attr.Attribute.NamespaceAndName, value);
                         }
                     }
@@ -362,6 +364,13 @@ namespace Svg
                     }
                 }
             }
+
+            //add the custom attributes
+            foreach (var item in this._customAttributes)
+            {
+                writer.WriteAttributeString(item.Key, item.Value);
+            }
+
         }
 
         protected virtual void Write(XmlTextWriter writer)