use rgba hexcodes not argb

README.md

@@ -172,7 +172,7 @@ If --username and/or --dbname are not specified the current username is used as
 
   --copyright                     (Default: '') glTF asset copyright
 
-  --default_color                 (Default: #FFFFFF) Default color, in (A)RGB order
+  --default_color                 (Default: #FFFFFF) Default color, in RGB(A) order
 
   --default_metallic_roughness    (Default: #008000) Default metallic roughness
 

src/wkb2gltf.core.tests/ColorTests.cs

@@ -1,23 +1,23 @@
-using System.Drawing;
-using NUnit.Framework;
+using NUnit.Framework;
 
 namespace Wkb2Gltf.Tests;
 
 public class ColorTests
 {
+
     [Test]
     public void HexColorToRgbTest()
     {
         var hexcolor = "#ff5555";
-        var color = ColorTranslator.FromHtml(hexcolor);
-        Assert.That(color.R == 255 && color.G == 85 && color.B == 85, Is.True);
+        var color = RgbaColor.FromHex(hexcolor);
+        Assert.That(color.R == 255 && color.G == 85 && color.B == 85);
     }
 
     [Test]
     public void HexColorWithAlphaToRgbaTest()
     {
-        var hexcolor = "#55ff5657";
-        var color = ColorTranslator.FromHtml(hexcolor);
-        Assert.That(color.A == 85 && color.R == 255 && color.G == 86 && color.B == 87, Is.True);
+        var hexcolor = "#FF000055";
+        var color = RgbaColor.FromHex(hexcolor);
+        Assert.That(color.A == 85 && color.R == 255 && color.G == 0 && color.B == 0);
     }
 }

src/wkb2gltf.core.tests/MaterialCreatorTests.cs

@@ -14,24 +14,20 @@ public class MaterialCreatorTests
     [Test]
     public void ColorConvertTest()
     {
-        var hex = "#E6008000";
-        var color = ColorTranslator.FromHtml(hex);
-        Assert.That(color.A == 230, Is.True);
-        Assert.That(color.R == 0, Is.True);
-        Assert.That(color.G == 128, Is.True);
+        var hex = "#FF000055";
+        var color = RgbaColor.FromHex(hex);
+        Assert.That(color.A == 85);
+        Assert.That(color.R == 255, Is.True);
+        Assert.That(color.G == 0, Is.True);
         Assert.That(color.B == 0, Is.True);
-        var hex2 = ColorTranslator.ToHtml(color);
-        Assert.That(hex.EndsWith(hex2.Substring(1, hex2.Length - 1)), Is.True);
     }
 
     [Test]
     public void MetallicRoughnessBaseColorTest()
     {
         // arrange
         var shader = new Shader();
-        // #008000 = green https://www.color-hex.com/color/008000 (0,128,0)), 81 as Alpha value
-        shader.PbrMetallicRoughness = new PbrMetallicRoughness() { BaseColor = "#81008000", MetallicRoughness = "" };
-
+        shader.PbrMetallicRoughness = new PbrMetallicRoughness() { BaseColor = "#00800081", MetallicRoughness = "" };
 
         // act
         var material = MaterialCreator.CreateMaterial(shader, true, AlphaMode.BLEND);
@@ -55,7 +51,7 @@ public void MetallicRoughnessBaseColorEmissiveTest()
         var emissive = new Vector3(10, 20, 30);
         // #008000 = green https://www.color-hex.com/color/008000 (0,128,0))
         shader.PbrMetallicRoughness = new PbrMetallicRoughness() { BaseColor = "#008000" };
-        shader.EmissiveColor = ColorTranslator.ToHtml(Color.FromArgb(10, 20, 30));
+        shader.EmissiveColor = RgbaColor.ToHex(Color.FromArgb(10, 20, 30));
         // act
         var material = MaterialCreator.CreateMaterial(shader);
 
@@ -85,7 +81,7 @@ public void MetallicRoughnessTest()
         var roughnessFactor = 0.4f;
 
         var c = Color.FromArgb((int)(metallicFactor * 255), ((int)(roughnessFactor * 255)), 0);
-        var hex = ColorTranslator.ToHtml(c);
+        var hex = RgbaColor.ToHex(c);
 
         shader.PbrMetallicRoughness = new PbrMetallicRoughness() { BaseColor = "#008000", MetallicRoughness = hex };
 
@@ -108,7 +104,7 @@ public void SpecularGlossinessWithDiffuseTest()
         var shader = new Shader();
         var diffuse = Color.FromArgb(10, 20, 30, 40); // diffuse rgb + alpha
         var specularGlossiness = Color.FromArgb(50, 60, 70, 80); // specular red, green, blue + glossiness
-        shader.PbrSpecularGlossiness = new PbrSpecularGlossiness() { DiffuseColor = ColorTranslator.ToHtml(diffuse), SpecularGlossiness = ColorTranslator.ToHtml(specularGlossiness) };
+        shader.PbrSpecularGlossiness = new PbrSpecularGlossiness() { DiffuseColor = RgbaColor.ToHex(diffuse), SpecularGlossiness = RgbaColor.ToHex(specularGlossiness) };
         // act
         var material = MaterialCreator.CreateMaterial(shader);
 
@@ -124,7 +120,7 @@ public void SpecularGlossinessTest()
     {
         var shader = new Shader();
         var specularGlossiness = Color.FromArgb(50, 60, 70, 80); // specular red, green, blue + glossiness
-        shader.PbrSpecularGlossiness = new PbrSpecularGlossiness() { SpecularGlossiness = ColorTranslator.ToHtml(specularGlossiness) };
+        shader.PbrSpecularGlossiness = new PbrSpecularGlossiness() { SpecularGlossiness = RgbaColor.ToHex(specularGlossiness) };
         // act
         var material = MaterialCreator.CreateMaterial(shader);
 

src/wkb2gltf.core/MaterialCreator.cs

@@ -13,7 +13,7 @@ public static MaterialBuilder CreateMaterial(Shader shader, bool defaultDoubleSi
             WithAlpha(defaultAlphaMode);
 
         if (!string.IsNullOrEmpty(shader.EmissiveColor)) {
-            material.WithEmissive(ColorToVector3(ColorTranslator.FromHtml(shader.EmissiveColor)));
+            material.WithEmissive(ColorToVector3(RgbaColor.FromHex(shader.EmissiveColor)));
         }
         if (shader.PbrSpecularGlossiness != null) {
 #pragma warning disable CS0618 // Type or member is obsolete
@@ -22,11 +22,11 @@ public static MaterialBuilder CreateMaterial(Shader shader, bool defaultDoubleSi
 
             if (!string.IsNullOrEmpty(shader.PbrSpecularGlossiness.DiffuseColor)) {
 #pragma warning disable CS0618 // Type or member is obsolete
-                material.WithDiffuse(ColorToVector4(ColorTranslator.FromHtml(shader.PbrSpecularGlossiness.DiffuseColor)));
+                material.WithDiffuse(ColorToVector4(RgbaColor.FromHex(shader.PbrSpecularGlossiness.DiffuseColor)));
 #pragma warning restore CS0618 // Type or member is obsolete
             }
             if (!string.IsNullOrEmpty(shader.PbrSpecularGlossiness.SpecularGlossiness)) {
-                var c = ColorToVector4(ColorTranslator.FromHtml(shader.PbrSpecularGlossiness.SpecularGlossiness));
+                var c = ColorToVector4(RgbaColor.FromHex(shader.PbrSpecularGlossiness.SpecularGlossiness));
                 var specular = new Vector3(c.X, c.Y, c.Z);
                 var glossiness = c.Z;
 #pragma warning disable CS0618 // Type or member is obsolete
@@ -37,11 +37,11 @@ public static MaterialBuilder CreateMaterial(Shader shader, bool defaultDoubleSi
         else if (shader.PbrMetallicRoughness != null) {
             material.WithMetallicRoughnessShader();
             if (!string.IsNullOrEmpty(shader.PbrMetallicRoughness.BaseColor)) {
-                material.WithBaseColor(ColorToVector4(ColorTranslator.FromHtml(shader.PbrMetallicRoughness.BaseColor)));
+                material.WithBaseColor(ColorToVector4(RgbaColor.FromHex(shader.PbrMetallicRoughness.BaseColor)));
             }
 
             if (!string.IsNullOrEmpty(shader.PbrMetallicRoughness.MetallicRoughness)) {
-                var html = ColorTranslator.FromHtml(shader.PbrMetallicRoughness.MetallicRoughness);
+                var html = RgbaColor.FromHex(shader.PbrMetallicRoughness.MetallicRoughness);
                 var c = ColorToVector4(html);
                 material.WithMetallicRoughness(c.X, c.Y);
             }

src/wkb2gltf.core/RgabColor.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Drawing;
+using System.Globalization;
+
+namespace Wkb2Gltf;
+
+public static class RgbaColor
+{
+    public static string ToHex(Color color)
+    {
+        return $"#{color.R:X2}{color.G:X2}{color.B:X2}{color.A:X2}";
+    }
+    public static Color FromHex(string hex)
+    {
+        var hexSpan = hex.AsSpan();
+
+        if (hexSpan.StartsWith("#")) {
+            hexSpan = hexSpan.Slice(1);
+        }
+
+        var rgb = GetRgb(hexSpan);
+
+        if (hexSpan.Length == 8) {
+            var alpha = byte.Parse(hexSpan.Slice(6, 2), NumberStyles.HexNumber);
+            return Color.FromArgb(alpha, rgb.red, rgb.green, rgb.blue);
+        }
+        else if (hexSpan.Length == 6) {
+            return Color.FromArgb(255, rgb.red, rgb.green, rgb.blue);
+        }
+        else {
+            throw new ArgumentException("Hex-color code must be 6 or 8 characters.");
+        }
+    }
+
+    private static (int red, int green, int blue) GetRgb(ReadOnlySpan<char> hexSpan)
+    {
+        var red = byte.Parse(hexSpan.Slice(0, 2), NumberStyles.HexNumber);
+        var green = byte.Parse(hexSpan.Slice(2, 2), NumberStyles.HexNumber);
+        var blue = byte.Parse(hexSpan.Slice(4, 2), NumberStyles.HexNumber);
+        return (red, green, blue);
+    }
+}

styling.md

@@ -45,7 +45,12 @@ Remember to add attribute bouwjaar with '-a bouwjaar' when creating the 3D Tiles
 ## Server side styling
 
 When using server side styling the 3D Tiles are styled in the database. 
-The styling is stored in a json document in a column of type json.
+
+The styling is stored in a json document in a column of type json. 
+
+A hex color notation is used for the colors, in the form of #RRGGBBAA. Sample:
+
+Hex code #FF000055 is Color red (r,g,b = 255,0,0) + Alpha = 85
 
 The json document contains the shaders for the 3D Tiles. When the option --shaderscolumn is used, the shaders are read from the column specified in the option.
 
@@ -62,7 +67,6 @@ Metallic factor: 0, Roughness factor: 0.5019608 (128/255)
 
 - Doubleside: true (option double_sided)
 
-
 Alternative option is to specify a shader using the ShadersColumn.
 
 Shaderscolumn is a column of type json. In the json documents the shaders are defined like PbrMetallicRoughness and