Using CRC32 for hash.

5 files changed, 15 insertions, 8 deletions

diff --git a/NesTiler/NesTiler.csproj b/NesTiler/NesTiler.csproj
index aac25f8..b50eec4 100644
--- a/NesTiler/NesTiler.csproj
+++ b/NesTiler/NesTiler.csproj
@@ -20,6 +20,7 @@
     <PackageReference Include="ColorMinePortable" Version="2.0.1" />

     <PackageReference Include="SkiaSharp" Version="2.88.3" />

     <PackageReference Include="SkiaSharp.NativeAssets.Linux.NoDependencies" Version="2.88.3" />

+    <PackageReference Include="System.IO.Hashing" Version="6.0.2" />

   </ItemGroup>

   <ItemGroup>

     <Compile Update="Properties\Resources.Designer.cs">

diff --git a/NesTiler/Tile.cs b/NesTiler/Tile.cs
index c3db539..e20d81d 100644
--- a/NesTiler/Tile.cs
+++ b/NesTiler/Tile.cs
@@ -1,6 +1,6 @@
 using System;

+using System.IO.Hashing;

 using System.Linq;

-using System.Security.AccessControl;

 

 namespace com.clusterrr.Famicom.NesTiler

 {

@@ -29,10 +29,10 @@ namespace com.clusterrr.Famicom.NesTiler
                 {

                     for (int x = 0; x < Width; x++)

                     {

-                        if ((Pixels[y * Width + x] & 1) != 0)

-                            data[pixel / 64 * 2 + y] |= (byte)(1 << bit);

-                        if ((Pixels[y * Width + x] & 2) != 0)

-                            data[pixel / 64 * 2 + y + 8] |= (byte)(1 << bit);

+                        if ((Pixels[(y * Width) + x] & 1) != 0)

+                            data[(pixel / 64 * 2) + y] |= (byte)(1 << bit);

+                        if ((Pixels[(y * Width) + x] & 2) != 0)

+                            data[(pixel / 64 * 2) + y + 8] |= (byte)(1 << bit);

                         pixel++;

                         bit = (byte)((byte)(bit - 1) % 8);

                     }

@@ -51,7 +51,10 @@ namespace com.clusterrr.Famicom.NesTiler
         public override int GetHashCode()

         {

             if (hash != null) return hash.Value;

-            hash = GetAsTileData().Sum(v => v);

+            var crc = new Crc32();

+            crc.Append(GetAsTileData());

+            var hashBytes = crc.GetCurrentHash();

+            hash = BitConverter.ToInt32(hashBytes, 0);

             return hash.Value;

         }

     }

diff --git a/Samples/nrom_split_lossy/Makefile b/Samples/nrom_split_lossy/Makefile
index f9bccf0..7d741c0 100644
--- a/Samples/nrom_split_lossy/Makefile
+++ b/Samples/nrom_split_lossy/Makefile
@@ -18,6 +18,8 @@ PALETTE_0_BIN=palette_0.bin
 PALETTE_1_BIN=palette_1.bin
 PALETTE_2_BIN=palette_2.bin
 PALETTE_3_BIN=palette_3.bin
+PREVIEW_1=preview1.png
+PREVIEW_2=preview2.png
 
 build: $(EXECUTABLE)
 
@@ -41,7 +43,8 @@ $(PATTERN_0_BIN) $(PATTERN_1_BIN) \
 $(NAME_TABLE_0_BIN) $(NAME_TABLE_1_BIN) \
 $(ATTR_TABLE_0_BIN) $(ATTR_TABLE_1_BIN) \
 $(PALETTE_0_BIN) $(PALETTE_1_BIN) \
-$(PALETTE_2_BIN) $(PALETTE_3_BIN): $(IMAGE)
+$(PALETTE_2_BIN) $(PALETTE_3_BIN) \
+$(PREVIEW_1) $(PREVIEW_2): $(IMAGE)
 	$(TILER) --mode bg --enable-palettes 0,1,2,3 \
 	--in-0 $(IMAGE):0:$(HEIGHT1) --in-1 $(IMAGE):$(HEIGHT1):$(HEIGHT2) \
 	--out-pattern-table-0 $(PATTERN_0_BIN) --out-pattern-table-1 $(PATTERN_1_BIN) \
@@ -49,4 +52,4 @@ $(PALETTE_2_BIN) $(PALETTE_3_BIN): $(IMAGE)
 	--out-attribute-table-0 $(ATTR_TABLE_0_BIN) --out-attribute-table-1 $(ATTR_TABLE_1_BIN) \
 	--out-palette-0 $(PALETTE_0_BIN) --out-palette-1 $(PALETTE_1_BIN) \
 	--out-palette-2 $(PALETTE_2_BIN) --out-palette-3 $(PALETTE_3_BIN) \
-    --lossy
+    --lossy --out-preview-0 $(PREVIEW_1) --out-preview-1 $(PREVIEW_2)
diff --git a/Samples/nrom_split_lossy/preview1.png b/Samples/nrom_split_lossy/preview1.png
new file mode 100644
index 0000000..f6fac89
--- /dev/null
+++ b/Samples/nrom_split_lossy/preview1.png
diff --git a/Samples/nrom_split_lossy/preview2.png b/Samples/nrom_split_lossy/preview2.png
new file mode 100644
index 0000000..f1254a3
--- /dev/null
+++ b/Samples/nrom_split_lossy/preview2.png