From e4051a3dacca35289e9f8993fb258648f8f9a9c5 Mon Sep 17 00:00:00 2001
From: Reporting Issue <>
Date: Thu, 14 Sep 2023 22:43:42 -0400
Subject: [PATCH] add opaque option to drawer properties + add background code

---
 .../ElementDrawers/DrawerOptions.cs           |  5 +++++
 src/BinaryKits.Zpl.Viewer/ZplElementDrawer.cs | 21 ++++++++++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/BinaryKits.Zpl.Viewer/ElementDrawers/DrawerOptions.cs b/src/BinaryKits.Zpl.Viewer/ElementDrawers/DrawerOptions.cs
index d87b2e63..38c0bbf3 100644
--- a/src/BinaryKits.Zpl.Viewer/ElementDrawers/DrawerOptions.cs
+++ b/src/BinaryKits.Zpl.Viewer/ElementDrawers/DrawerOptions.cs
@@ -10,6 +10,11 @@ public class DrawerOptions
 
         public SKEncodedImageFormat RenderFormat { get; set; } = SKEncodedImageFormat.Png;
 
+        /// <summary>
+        /// Applies label over a white background after rendering all elements
+        /// </summary>
+        public bool OpaqueBackground { get; set; } = false;
+
         public int RenderQuality { get; set; } = 80;
 
         public bool ReplaceDashWithEnDash { get; set; } = true;
diff --git a/src/BinaryKits.Zpl.Viewer/ZplElementDrawer.cs b/src/BinaryKits.Zpl.Viewer/ZplElementDrawer.cs
index b8d11d0a..7291f6c2 100644
--- a/src/BinaryKits.Zpl.Viewer/ZplElementDrawer.cs
+++ b/src/BinaryKits.Zpl.Viewer/ZplElementDrawer.cs
@@ -100,7 +100,26 @@ public byte[] Draw(
                 }
             }
 
-            using var data = skBitmap.Encode(_drawerOptions.RenderFormat, _drawerOptions.RenderQuality);
+            SKBitmap finalBitmap;
+            if (this._drawerOptions.OpaqueBackground == true)
+            {
+                finalBitmap = new SKBitmap(labelImageWidth, labelImageHeight);
+                using (SKCanvas canvas = new SKCanvas(finalBitmap))
+                {
+                    SKPaint paint = new SKPaint
+                    {
+                        IsAntialias = true,
+                        FilterQuality = SKFilterQuality.High
+                    };
+                    canvas.Clear(SKColors.White);
+                    canvas.DrawBitmap(skBitmap, 0, 0, paint);
+                }
+            }
+            else {
+                finalBitmap = skBitmap;
+            }
+
+            using var data = finalBitmap.Encode(_drawerOptions.RenderFormat, _drawerOptions.RenderQuality);
             return data.ToArray();
         }