Add default colour quantization support

Pixi/Common/ColorSpaceUtility.cs

@@ -65,6 +65,14 @@ namespace Pixi.Common
 		[MethodImpl(MethodImplOptions.AggressiveInlining)]
         public static BlockColor QuantizeToBlockColor(float[] pixel)
 		{
+			if (pixel.Length < 3 || pixel[0] < 0 || pixel[1] < 0 || pixel[2] < 0)
+			{
+				return new BlockColor
+				{
+					Color = BlockColors.Default,
+					Darkness = 0,
+				};
+			}
 			return QuantizeToBlockColor(new Color(pixel[0], pixel[1], pixel[2]));
 		}
 
@@ -229,6 +237,8 @@ namespace Pixi.Common
             colorMap[new BlockColor { Color = BlockColors.Red, Darkness = 7 }] = new float[3] { 0.455f, 0.105f, 0.108f };
             colorMap[new BlockColor { Color = BlockColors.Red, Darkness = 8 }] = new float[3] { 0.320f, 0.121f, 0.133f };
             colorMap[new BlockColor { Color = BlockColors.Red, Darkness = 9 }] = new float[3] { 0.687f, 0.571f, 0.661f };
+            // default
+            colorMap[new BlockColor { Color = BlockColors.Default, Darkness = 0 }] = new float[3] { -1f, -1f, -1f };
         }
 
         private static void BuildBotColorMap()

Pixi/Images/ImageCommandImporter.cs

@@ -54,7 +54,11 @@ namespace Pixi.Images
             commandBlockContents[name] = text;
             return new BlockJsonInfo[]
             {
-                new BlockJsonInfo {name = "ConsoleBlock"}
+                new BlockJsonInfo
+                {
+                    color = new float[] {-1f, -1f, -1f},
+                    name = "ConsoleBlock"
+                }
             };
         }
 

Pixi/Images/ImageTextBlockImporter.cs

@@ -65,7 +65,7 @@ namespace Pixi.Images
             {
                 new BlockJsonInfo
                 {
-                    color = new float[] {0f, 0f, 0f},
+                    color = new float[] {-1f, -1f, -1f},
                     name = "TextBlock",
                     position = new float[] {0f, 0f, 0f},
                     rotation = new float[] {0f, 0f, 0f},

Pixi/Images/PixelUtility.cs

@@ -18,18 +18,38 @@ namespace Pixi.Images
 		{
 			return "#"+ColorUtility.ToHtmlStringRGBA(pixel);
 		}
+		
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		public static Color PixelHex(string hex)
+		{
+			if (ColorUtility.TryParseHtmlString(hex, out Color result))
+			{
+				return result;
+			}
+			return default;
+		}
 
 		public static string TextureToString(Texture2D img)
 		{
 			StringBuilder imgString = new StringBuilder("<cspace=-0.13em><line-height=40%>");
+			bool lastPixelAssigned = false;
+			Color lastPixel = new Color();
 			for (int y = img.height-1; y >= 0 ; y--) // text origin is top right, but img origin is bottom right
             {
 				for (int x = 0; x < img.width; x++)
                 {
                     Color pixel = img.GetPixel(x, y);
-                    imgString.Append("<color=");
+                    if (!lastPixelAssigned || lastPixel != pixel)
-                    imgString.Append(HexPixel(pixel));
+                    {
-					imgString.Append(">");
+	                    imgString.Append("<color=");
+	                    imgString.Append(HexPixel(pixel));
+	                    imgString.Append(">");
+	                    lastPixel = pixel;
+	                    if (!lastPixelAssigned)
+	                    {
+		                    lastPixelAssigned = true;
+	                    }
+                    }
                     imgString.Append("\u25a0");
                 }
                 imgString.Append("<br>");