Add some tileset tests

DotTiled.Tests/Serialization/TestData.cs

@@ -37,6 +37,7 @@ public static partial class TestData
     ["Serialization/TestData/Map/map_with_embedded_tileset/map-with-embedded-tileset", (string f) => TestData.MapWithEmbeddedTileset(), Array.Empty<CustomTypeDefinition>()],
     ["Serialization/TestData/Map/map_with_external_tileset/map-with-external-tileset", (string f) => TestData.MapWithExternalTileset(f), Array.Empty<CustomTypeDefinition>()],
     ["Serialization/TestData/Map/map_with_flippingflags/map-with-flippingflags", (string f) => TestData.MapWithFlippingFlags(f), Array.Empty<CustomTypeDefinition>()],
+    ["Serialization/TestData/Map/map_external_tileset_multi/map-external-tileset-multi", (string f) => TestData.MapExternalTilesetMulti(f), Array.Empty<CustomTypeDefinition>()],
   ];
 
   private static CustomTypeDefinition[] typedefs = [

DotTiled.Tests/Serialization/TestData/Map/map-external-tileset-multi/map-external-tileset-multi.cs

@@ -0,0 +1,121 @@
+using System.Globalization;
+
+namespace DotTiled.Tests;
+
+public partial class TestData
+{
+  public static Map MapExternalTilesetMulti(string fileExt) => new Map
+  {
+    Class = "",
+    Orientation = MapOrientation.Orthogonal,
+    Width = 5,
+    Height = 5,
+    TileWidth = 32,
+    TileHeight = 32,
+    Infinite = false,
+    HexSideLength = null,
+    StaggerAxis = null,
+    StaggerIndex = null,
+    ParallaxOriginX = 0,
+    ParallaxOriginY = 0,
+    RenderOrder = RenderOrder.RightDown,
+    CompressionLevel = -1,
+    BackgroundColor = Color.Parse("#00000000", CultureInfo.InvariantCulture),
+    Version = "1.10",
+    TiledVersion = "1.11.0",
+    NextLayerID = 2,
+    NextObjectID = 1,
+    Tilesets = [
+      new Tileset
+      {
+        TileOffset = new TileOffset
+        {
+          X = 1,
+          Y = 5
+        },
+        Version = "1.10",
+        TiledVersion = "1.11.0",
+        FirstGID = 1,
+        Name = "multi-tileset",
+        TileWidth = 256,
+        TileHeight = 96,
+        TileCount = 2,
+        Columns = 0,
+        Source = $"multi-tileset.{(fileExt == "tmx" ? "tsx" : "tsj")}",
+        Grid = new Grid
+        {
+          Orientation = GridOrientation.Orthogonal,
+          Width = 1,
+          Height = 1
+        },
+        Properties = new Dictionary<string, IProperty>
+        {
+          ["tilesetbool"] = new BoolProperty { Name = "tilesetbool", Value = true },
+          ["tilesetcolor"] = new ColorProperty { Name = "tilesetcolor", Value = Color.Parse("#ffff0000", CultureInfo.InvariantCulture) },
+          ["tilesetfile"] = new FileProperty { Name = "tilesetfile", Value = "" },
+          ["tilesetfloat"] = new FloatProperty { Name = "tilesetfloat", Value = 5.2f },
+          ["tilesetint"] = new IntProperty { Name = "tilesetint", Value = 9 },
+          ["tilesetobject"] = new ObjectProperty { Name = "tilesetobject", Value = 0 },
+          ["tilesetstring"] = new StringProperty { Name = "tilesetstring", Value = "hello world!" }
+        },
+        Tiles = [
+          new Tile
+          {
+            ID = 0,
+            Width = 256,
+            Height = 96,
+            Image = new Image
+            {
+              Format = ImageFormat.Png,
+              Source = "tileset.png",
+              Width = 256,
+              Height = 96
+            }
+          },
+          new Tile
+          {
+            ID = 1,
+            Width = 256,
+            Height = 96,
+            Image = new Image
+            {
+              Format = ImageFormat.Png,
+              Source = "tileset.png",
+              Width = 256,
+              Height = 96
+            }
+          }
+        ]
+      }
+    ],
+    Layers = [
+      new TileLayer
+      {
+        ID = 1,
+        Name = "Tile Layer 1",
+        Width = 5,
+        Height = 5,
+        Data = new Data
+        {
+          Encoding = DataEncoding.Csv,
+          Chunks = null,
+          Compression = null,
+          GlobalTileIDs = [
+            0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0,
+            1, 0, 0, 0, 0,
+            0, 0, 0, 0, 0,
+            0, 2, 0, 0, 0
+          ],
+          FlippingFlags = [
+            FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None,
+            FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None,
+            FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None,
+            FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None,
+            FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None, FlippingFlags.None
+          ]
+        }
+      }
+    ]
+  };
+}

DotTiled.Tests/Serialization/TestData/Map/map-external-tileset-multi/map-external-tileset-multi.tmj

@@ -0,0 +1,36 @@
+{ "compressionlevel":-1,
+ "height":5,
+ "infinite":false,
+ "layers":[
+        {
+         "data":[0, 0, 0, 0, 0,
+            0, 0, 0, 0, 0,
+            1, 0, 0, 0, 0,
+            0, 0, 0, 0, 0,
+            0, 2, 0, 0, 0],
+         "height":5,
+         "id":1,
+         "name":"Tile Layer 1",
+         "opacity":1,
+         "type":"tilelayer",
+         "visible":true,
+         "width":5,
+         "x":0,
+         "y":0
+        }],
+ "nextlayerid":2,
+ "nextobjectid":1,
+ "orientation":"orthogonal",
+ "renderorder":"right-down",
+ "tiledversion":"1.11.0",
+ "tileheight":32,
+ "tilesets":[
+        {
+         "firstgid":1,
+         "source":"multi-tileset.tsj"
+        }],
+ "tilewidth":32,
+ "type":"map",
+ "version":"1.10",
+ "width":5
+}

DotTiled.Tests/Serialization/TestData/Map/map-external-tileset-multi/map-external-tileset-multi.tmx

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<map version="1.10" tiledversion="1.11.0" orientation="orthogonal" renderorder="right-down" width="5" height="5" tilewidth="32" tileheight="32" infinite="0" nextlayerid="2" nextobjectid="1">
+ <tileset firstgid="1" source="multi-tileset.tsx"/>
+ <layer id="1" name="Tile Layer 1" width="5" height="5">
+  <data encoding="csv">
+0,0,0,0,0,
+0,0,0,0,0,
+1,0,0,0,0,
+0,0,0,0,0,
+0,2,0,0,0
+</data>
+ </layer>
+</map>

DotTiled.Tests/Serialization/TestData/Map/map-external-tileset-multi/multi-tileset.tsj

@@ -0,0 +1,71 @@
+{ "columns":0,
+ "grid":
+    {
+     "height":1,
+     "orientation":"orthogonal",
+     "width":1
+    },
+ "margin":0,
+ "name":"multi-tileset",
+ "properties":[
+        {
+         "name":"tilesetbool",
+         "type":"bool",
+         "value":true
+        }, 
+        {
+         "name":"tilesetcolor",
+         "type":"color",
+         "value":"#ffff0000"
+        }, 
+        {
+         "name":"tilesetfile",
+         "type":"file",
+         "value":""
+        }, 
+        {
+         "name":"tilesetfloat",
+         "type":"float",
+         "value":5.2
+        }, 
+        {
+         "name":"tilesetint",
+         "type":"int",
+         "value":9
+        }, 
+        {
+         "name":"tilesetobject",
+         "type":"object",
+         "value":0
+        }, 
+        {
+         "name":"tilesetstring",
+         "type":"string",
+         "value":"hello world!"
+        }],
+ "spacing":0,
+ "tilecount":2,
+ "tiledversion":"1.11.0",
+ "tileheight":96,
+ "tileoffset":
+    {
+     "x":1,
+     "y":5
+    },
+ "tiles":[
+        {
+         "id":0,
+         "image":"tileset.png",
+         "imageheight":96,
+         "imagewidth":256
+        }, 
+        {
+         "id":1,
+         "image":"tileset.png",
+         "imageheight":96,
+         "imagewidth":256
+        }],
+ "tilewidth":256,
+ "type":"tileset",
+ "version":"1.10"
+}

DotTiled.Tests/Serialization/TestData/Map/map-external-tileset-multi/multi-tileset.tsx

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<tileset version="1.10" tiledversion="1.11.0" name="multi-tileset" tilewidth="256" tileheight="96" tilecount="2" columns="0">
+ <tileoffset x="1" y="5"/>
+ <grid orientation="orthogonal" width="1" height="1"/>
+ <properties>
+  <property name="tilesetbool" type="bool" value="true"/>
+  <property name="tilesetcolor" type="color" value="#ffff0000"/>
+  <property name="tilesetfile" type="file" value=""/>
+  <property name="tilesetfloat" type="float" value="5.2"/>
+  <property name="tilesetint" type="int" value="9"/>
+  <property name="tilesetobject" type="object" value="0"/>
+  <property name="tilesetstring" value="hello world!"/>
+ </properties>
+ <tile id="0">
+  <image source="tileset.png" width="256" height="96"/>
+ </tile>
+ <tile id="1">
+  <image source="tileset.png" width="256" height="96"/>
+ </tile>
+</tileset>

DotTiled/Serialization/Tmj/Tmj.Tileset.cs

@@ -77,14 +77,14 @@ internal partial class Tmj
       return resolvedTileset;
     }
 
-    var imageModel = new Image
+    var imageModel = image is not null ? new Image
     {
-      Format = Helpers.ParseImageFormatFromSource(image!),
+      Format = Helpers.ParseImageFormatFromSource(image),
       Source = image,
       Height = imageHeight,
       Width = imageWidth,
       TransparentColor = transparentColor
-    };
+    } : null;
 
     return new Tileset
     {
@@ -159,7 +159,7 @@ internal partial class Tmj
       var width = e.GetOptionalProperty<uint>("width", imageWidth ?? 0);
       var height = e.GetOptionalProperty<uint>("height", imageHeight ?? 0);
       var objectGroup = e.GetOptionalPropertyCustom<ObjectLayer?>("objectgroup", e => ReadObjectLayer(e, externalTemplateResolver, customTypeDefinitions), null);
-      var probability = e.GetOptionalProperty<float>("probability", 1.0f);
+      var probability = e.GetOptionalProperty<float>("probability", 0.0f);
       var properties = e.GetOptionalPropertyCustom<Dictionary<string, IProperty>?>("properties", el => ReadProperties(el, customTypeDefinitions), null);
       // var terrain, replaced by wangsets
       var type = e.GetOptionalProperty<string>("type", "");