always write colors with 3 decimal places

Author: brettfo

src/IxMilia.Pdf.Test/PdfWriterTests.cs

@@ -53,11 +53,11 @@ 3 0 obj
 <</Type /Page /Parent 2 0 R /Contents 4 0 R /MediaBox [0 0 612.00 792.00] /Resources <<>>>>
 endobj
 4 0 obj
-<</Length 28>>
+<</Length 52>>
 stream
 0 w
-0 0 0 RG
-0 0 0 rg
+0.000 0.000 0.000 RG
+0.000 0.000 0.000 rg
 S
 endstream
 endobj
@@ -70,7 +70,7 @@ 0000000125 00000 n
 0000000235 00000 n
 trailer <</Size 5 /Root 1 0 R>>
 startxref
-315
+339
 %%EOF
 ";
             AssertFileEquals(file, expected);
@@ -131,8 +131,8 @@ public void VerifyLineStrokeTest()
             };
             AssertPathBuilderContains(builder, @"
 0 w
-0 0 0 RG
-0 0 0 rg
+0.000 0.000 0.000 RG
+0.000 0.000 0.000 rg
 0.00 0.00 m
 1.00 1.00 l
 S
@@ -141,12 +141,12 @@ 2.00 2.00 m
 3.00 3.00 l
 S
 0 w
-1 0 0 RG
+1.000 0.000 0.000 RG
 4.00 4.00 m
 5.00 5.00 l
 S
 2.2 w
-0 1 0 RG
+0.000 1.000 0.000 RG
 6.00 6.00 m
 7.00 7.00 l
 S
@@ -176,8 +176,8 @@ public void VerifyFillTest()
             };
             AssertPathBuilderContains(builder, @"
 0 w
-0 0 0 RG
-0 0 0 rg
+0.000 0.000 0.000 RG
+0.000 0.000 0.000 rg
 0.00 0.00 m
 1.00 1.00 l
 S
@@ -186,12 +186,12 @@ 2.00 2.00 m
 3.00 3.00 l
 S
 0 w
-1 0 0 rg
+1.000 0.000 0.000 rg
 4.00 4.00 m
 5.00 5.00 l
 S
 2.2 w
-0 1 0 rg
+0.000 1.000 0.000 rg
 6.00 6.00 m
 7.00 7.00 l
 S
@@ -478,12 +478,12 @@ public void VerifyStreamFilterTest()
             page.Items.Add(text);
 
             var expected = @"
-<</Length 185
+<</Length 233
   /Filter [/ASCIIHexDecode]
 >>
 stream
-3020770D0A30203020302052470D0A30203020302072670D0A42540D0A202020202F46312031322E30302054660D0A2020202037322E30302037322E30302054
-640D0A202020205B28666F6F295D20544A0D0A45540D0A530D0A>
+3020770D0A302E30303020302E30303020302E3030302052470D0A302E30303020302E30303020302E3030302072670D0A42540D0A202020202F46312031322E
+30302054660D0A2020202037322E30302037322E30302054640D0A202020205B28666F6F295D20544A0D0A45540D0A530D0A>
 endstream
 endobj
 ";

src/IxMilia.Pdf/Extensions/WriterExtensions.cs

@@ -1,9 +1,12 @@
 using System.Globalization;
+using System.Text.RegularExpressions;
 
 namespace IxMilia.Pdf.Extensions
 {
     internal static class WriterExtensions
     {
+        private static readonly Regex NegativeZero = new Regex(@"^-0(\.0+)?$", RegexOptions.Compiled);
+
         public static string AsObjectReference(this int objectId)
         {
             return $"{objectId} 0 R";
@@ -14,13 +17,14 @@ public static string AsInvariant(this double value)
             return value.ToString(CultureInfo.InvariantCulture);
         }
 
-        public static string AsFixed(this double value)
+        public static string AsFixed(this double value, int decimalPlaces = 2)
         {
-            var str = value.ToString("f2", CultureInfo.InvariantCulture);
+            var str = value.ToString($"f{decimalPlaces}", CultureInfo.InvariantCulture);
+
             // special case for really small negative values that round to 0
-            if (str == "-0.00")
+            if (NegativeZero.IsMatch(str))
             {
-                str = "0.00";
+                str = str.Substring(1);
             }
 
             return str;

src/IxMilia.Pdf/PdfColor.cs

@@ -4,6 +4,8 @@ namespace IxMilia.Pdf
 {
     public struct PdfColor
     {
+        private static readonly int DecimalPlaces = 3;
+
         public double R { get; set; }
         public double G { get; set; }
         public double B { get; set; }
@@ -17,7 +19,7 @@ public PdfColor(double r, double g, double b)
 
         public override string ToString()
         {
-            return $"{R.AsInvariant()} {G.AsInvariant()} {B.AsInvariant()}";
+            return $"{R.AsFixed(DecimalPlaces)} {G.AsFixed(DecimalPlaces)} {B.AsFixed(DecimalPlaces)}";
         }
 
         public static bool operator ==(PdfColor a, PdfColor b)