Add missing readonly rule for some controls

Author: otuncelli

SvgFileType/SvgFileType.cs

@@ -99,12 +99,18 @@ PropertyControlInfo CommonSettings(PropertyControlInfo p)
 
     public override PropertyCollection OnCreateSavePropertyCollection()
     {
-        PropertyName[] targets = new PropertyName[] 
+        PropertyName[] targets1 = new PropertyName[] 
         {
             PropertyNames.PdnShape, 
             PropertyNames.PdnShapeName 
         };
 
+        PropertyName[] targets2 = new PropertyName[]
+        {
+            PropertyNames.LowpassFilter,
+            PropertyNames.GreymapScale
+        };
+
         FluentPropertyCollection properties = new FluentPropertyCollection()
             .AddStaticListChoice(PropertyNames.ScanMode, ScanMode.Transparent)
             .AddStaticListChoice(PropertyNames.PreviewMode, PreviewMode.Fast)
@@ -127,7 +133,8 @@ public override PropertyCollection OnCreateSavePropertyCollection()
             .AddDouble(PropertyNames.Angle, 0, 0, 360)
             .AddUri(PropertyNames.GitHubLink, MyPluginSupportInfo.Instance.WebsiteUri)
             .AddUri(PropertyNames.DiscussionLink, MyPluginSupportInfo.Instance.ForumUri)
-            .WithReadOnlyRule(targets, PropertyNames.ScanMode, ScanMode.Transparent, inverse: true)
+            .WithReadOnlyRule(targets1, PropertyNames.ScanMode, ScanMode.Transparent, inverse: true)
+            .WithReadOnlyRule(targets2, PropertyNames.HighpassFilter, 0)
             .WithReadOnlyRule(PropertyNames.FillColor, PropertyNames.ScanMode, ScanMode.Opaque, inverse: true);
         return properties;
     }