Paint.NET Tex Plugin

A Paint.NET plugin by RitoShark that opens and saves League of Legends .tex texture files. It auto-detects compression and mipmaps on open, and gives you a normal save option or a save option with full settings.

Download the latest release

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What it does

• Opens .tex files in Paint.NET (DXT1, DXT5, BC5, BC7, and BGRA8).
• Saves .tex files. Auto-detects compression and mipmaps when you save.
• Adds a second save option with a menu for picking compression, dithering, error metric, and mipmap settings.
• Compresses BC7 fast with a native helper DLL. Falls back to slow software BC7 without it.
• Keeps the full alpha channel.
• Uses Floyd-Steinberg error diffusion dithering for clean results.

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Before you start

You need:

• Paint.NET 5.1 or later (uses .NET 9). The latest 5.1.x build is recommended.
• Windows 10 or later.
• The latest release from the releases page: either the TexFileTypeSetup.exe installer, or the TexFileType.dll and Bc7Native.dll files for a manual install.

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Install with the installer

1. Close Paint.NET if it is open.
2. Download TexFileTypeSetup.exe from the latest release.
3. Run it. The installer finds your Paint.NET FileTypes folder and copies both DLLs for you.
4. Open Paint.NET. The plugin loads on startup.

Install manually

Use this if you prefer not to run the installer, or you use portable Paint.NET.

1. Close Paint.NET if it is open.
2. Open the Paint.NET FileTypes folder. For most installs that is C:\Program Files\Paint.NET\FileTypes. For portable Paint.NET, use [Paint.NET folder]\FileTypes.
3. Copy both TexFileType.dll and Bc7Native.dll from the release into the FileTypes folder. Keep them together.
4. Open Paint.NET. The plugin loads on startup.

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Open a .tex file

You have two ways to open a .tex file:

1. In Paint.NET, click File → Open and pick your .tex file.
2. Or drag the .tex file straight onto the Paint.NET window.

The texture appears on the canvas. Mipmaps and compression are read automatically.

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Save a .tex file

You have two save modes. Use the first one for normal work. Use the second one when you need control over compression or mipmaps.

Save with auto settings

1. Click File → Save As.
2. In the file type dropdown, pick League of Legends TEX.
3. Click Save.

The plugin keeps the compression and mipmap setup it detected when you opened the file.

Save with custom settings

1. Click File → Save As.
2. In the file type dropdown, pick League of Legends TEX (with options).
3. Pick your settings in the menu:
   • Compression: DXT1, DXT5, BC5, BC7, or BGRA8 (uncompressed). Use DXT5 or BC7 for textures with alpha. Use BC5 for normal maps.
   • Dithering: Floyd-Steinberg, for smoother gradients.
   • Error metric: Perceptual (recommended) or Uniform. This applies to DXT1 and DXT5 only.
   • Mipmaps: generate a full mipmap chain.
4. Click Save.

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How to check it worked

• Re-open the file you saved. It loads without errors and looks the same.
• Or load it in your skin tool (Flint or LtMAO) and it shows up correctly.

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Troubleshooting

Paint.NET crashes or the file doesn't load

Update Paint.NET to the latest 5.1.x build. The plugin needs 5.1 or later.

Plugin doesn't appear in Paint.NET

Close Paint.NET completely, then check these things:

• The folder C:\Program Files\Paint.NET\FileTypes exists.
• Both TexFileType.dll and Bc7Native.dll are inside that folder.
• You are not running an older Paint.NET (below 5.1).

Open Paint.NET again. The plugin should now show up in the file type list.

BC7 saves are very slow

Bc7Native.dll is missing from your FileTypes folder. Copy it in next to TexFileType.dll, then restart Paint.NET. The installer adds it for you.

"There was an error while saving the file."

Check your canvas size. Both width and height must be divisible by 4. League requires this for .tex files. Resize the image and save again.

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Credits

• Plugin by RitoShark.
• .tex reading logic from LtMAO by Tarngaina.
• BC1 and BC3 compression with Floyd-Steinberg dithering is based on Microsoft DirectXTex (MIT License).

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