Tidy up

Author: BobLd

src/UglyToad.PdfPig/Graphics/CurrentGraphicsState.cs

@@ -104,7 +104,7 @@ public class CurrentGraphicsState : IDeepCloneable<CurrentGraphicsState>
         public IColor CurrentNonStrokingColor { get; set; }
 
         /// <summary>
-        /// TODO.
+        /// The current blend mode.
         /// </summary>
         public BlendMode BlendMode { get; set; } = BlendMode.Normal;
 

src/UglyToad.PdfPig/Graphics/InlineImageBuilder.cs

@@ -62,17 +62,17 @@ internal InlineImage CreateInlineImage(
             {
                 if (!sMaskToken.StreamDictionary.TryGet(NameToken.Subtype, out NameToken softMaskSubType) || !softMaskSubType.Equals(NameToken.Image))
                 {
-                    throw new Exception("");
+                    throw new Exception("The SMask dictionary does not contain a 'Subtype' entry, or its value is not 'Image'.");
                 }
 
                 if (!sMaskToken.StreamDictionary.TryGet(NameToken.ColorSpace, out NameToken softMaskColorSpace) || !softMaskColorSpace.Equals(NameToken.Devicegray))
                 {
-                    throw new Exception("");
+                    throw new Exception("The SMask dictionary does not contain a 'ColorSpace' entry, or its value is not 'Devicegray'.");
                 }
 
                 if (sMaskToken.StreamDictionary.ContainsKey(NameToken.Mask) || sMaskToken.StreamDictionary.ContainsKey(NameToken.Smask))
                 {
-                    throw new Exception("");
+                    throw new Exception("The SMask dictionary contains a 'Mask' or 'Smask' entry.");
                 }
 
                 XObjectContentRecord softMaskImageRecord = new XObjectContentRecord(XObjectType.Image, sMaskToken, TransformationMatrix.Identity,

src/UglyToad.PdfPig/Graphics/SoftMask.cs

@@ -9,7 +9,7 @@
     using UglyToad.PdfPig.Util;
 
     /// <summary>
-    /// TODO.
+    /// Soft Mask.
     /// </summary>
     public sealed class SoftMask
     {
@@ -154,12 +154,12 @@ internal static SoftMask Parse(DictionaryToken dictionaryToken, IPdfTokenScanner
     public enum SoftMaskType : byte
     {
         /// <summary>
-        /// TODO.
+        /// Alpha - The group's computed alpha shall be used, disregarding its colour.
         /// </summary>
         Alpha = 0,
 
         /// <summary>
-        /// TODO.
+        /// Luminosity - The group's computed colour shall be converted to a single-component luminosity value.
         /// </summary>
         Luminosity = 1
     }

src/UglyToad.PdfPig/XObjects/XObjectFactory.cs

@@ -50,17 +50,17 @@ public static XObjectImage ReadImage(XObjectContentRecord xObject,
             {
                 if (!sMaskToken.StreamDictionary.TryGet(NameToken.Subtype, out NameToken softMaskSubType) || !softMaskSubType.Equals(NameToken.Image))
                 {
-                    throw new Exception("");
+                    throw new Exception("The SMask dictionary does not contain a 'Subtype' entry, or its value is not 'Image'.");
                 }
 
                 if (!sMaskToken.StreamDictionary.TryGet(NameToken.ColorSpace, out NameToken softMaskColorSpace) || !softMaskColorSpace.Equals(NameToken.Devicegray))
                 {
-                    throw new Exception("");
+                    throw new Exception("The SMask dictionary does not contain a 'ColorSpace' entry, or its value is not 'Devicegray'.");
                 }
 
                 if (sMaskToken.StreamDictionary.ContainsKey(NameToken.Mask) || sMaskToken.StreamDictionary.ContainsKey(NameToken.Smask))
                 {
-                    throw new Exception("");
+                    throw new Exception("The SMask dictionary contains a 'Mask' or 'Smask' entry.");
                 }
 
                 var renderingIntent = xObject.DefaultRenderingIntent; // Ignored