Initial alpha model support

Thief Mission Viewer.csproj

@@ -1,13 +1,10 @@
 <Project Sdk="Godot.NET.Sdk/4.3.0">
   <PropertyGroup>
     <TargetFramework>net8.0</TargetFramework>
-    <!-- <TargetFramework Condition=" '$(GodotTargetPlatform)' == 'android' ">net7.0</TargetFramework>
-    <TargetFramework Condition=" '$(GodotTargetPlatform)' == 'ios' ">net8.0</TargetFramework> -->
     <EnableDynamicLoading>true</EnableDynamicLoading>
     <RootNamespace>ThiefMissionViewer</RootNamespace>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="rectpacksharp" Version="1.2.0" />
     <PackageReference Include="SixLabors.ImageSharp" Version="3.1.5" />
   </ItemGroup>
 </Project>

project/code/TMV/Mission.cs

@@ -284,7 +284,8 @@ public partial class Mission : Node3D
 					{
 						var overrideMat = new StandardMaterial3D
 						{
-							AlbedoTexture = TextureLoader.LoadTexture(path)
+							AlbedoTexture = TextureLoader.LoadTexture(path),
+							Transparency = BaseMaterial3D.TransparencyEnum.AlphaDepthPrePass,
 						};
 
 						var surfaceCount = model.Mesh.GetSurfaceCount();

project/code/TMV/ModelLoader.cs

@@ -65,7 +65,8 @@ public class ModelLoader
 
                 var mat = new StandardMaterial3D
                 {
-                    AlbedoTexture = TextureLoader.LoadTexture(path)
+                    AlbedoTexture = TextureLoader.LoadTexture(path),
+                    Transparency = BaseMaterial3D.TransparencyEnum.AlphaDepthPrePass,
                 };
                 var name = material.Name.ToLower();
                 for (var i = 0; i < 4; i++)

project/code/TMV/TextureLoader.Gif.cs

@@ -6,6 +6,7 @@ namespace KeepersCompound.TMV;
 public partial class TextureLoader
 {
     // TODO: Replace this with my own implementation lol
+    // TODO: Alpha!?
     // References:
     // - https://www.w3.org/Graphics/GIF/spec-gif89a.txt
     private static ImageTexture LoadGif(string path)

project/code/TMV/TextureLoader.Pcx.cs

@@ -38,7 +38,8 @@ public partial class TextureLoader
                     var r = reader.ReadByte() / 255.0f;
                     var g = reader.ReadByte() / 255.0f;
                     var b = reader.ReadByte() / 255.0f;
-                    palette[i] = new Color(r, g, b);
+                    var a = (i == 0) ? 0.0f : 1.0f;
+                    palette[i] = new Color(r, g, b, a);
                 }
             }