# SourceIO brings Source engine assets into Blender

> SourceIO is a Blender addon that imports Source 1 and Source 2 models, maps, textures, and materials so you can reuse game assets in Blender. It covers many games fully, but it is an importer only, and several formats are explicitly not planned for export.

**REDxEYE/SourceIO** — SourceIO is an Blender(4.0+) addon for importing source engine textures/models/maps

- Repository: https://github.com/REDxEYE/SourceIO
- Website: https://discord.gg/XJvhzaXZf3
- Stars: 980 · Forks: 85
- Language: Python
- License: MIT
- Published: 2026-10-20 · Updated: 2026-10-20 · Language: en
- Canonical page: https://hysenlabs.com/projects/redxeye-sourceio

## The addon sits inside Blender as an import menu entry

SourceIO is not a standalone converter and it does not run from a command line. It is a Blender addon, which means it lives inside Blender's own extension machinery and appears in the application's menus. The README explains how to find it: to find the import tools you go to File, then Import, then Source Engine Assets. That single menu path is the entire user interface of the tool as described in the documentation. The project is written in Python, and the repository layout shows why a plain file tree contains no binary: there is an __init__.py at the top level, a blender_bindings directory, a library directory, a logger.py module, a tests directory, and a wiki directory. The blender_bindings folder is the layer that talks to Blender itself, while library holds the format handling, and the presence of a logger module and a tests folder tells you the project treats failures as something to trace rather than swallow.

## Getting the addon and finding the menu entry

The README does not give a command line install. It points to a download of the master branch archive from the project page, and to a Discord server, and it links a small wiki plus a TODO file for the current work list. The download link published in the README badge resolves to the master branch zip of the repository, so installing means fetching that archive and enabling it as an addon inside your Blender installation. Since no install command is documented, there is no command to copy here, and anyone who wants a reproducible setup should take the version from a release rather than from the moving master branch. The README badge also states a Blender version requirement of 4.5 or newer, while the project description in the same document says Blender 4.0 or later, so the version you can actually rely on is the one stated on the release you download. The Counter Strike 2 row in the supported games table adds its own note that it requires Blender 3.4 or newer.

## Source 1 formats import cleanly, export does not exist

The format tables are the most useful thing in the README, and the Source 1 table is stark. MDL, the model format, imports. BSP, compiled map files, imports. VTF, textures, imports. VMT, materials, imports. The export column for MDL, VTF, and VMT is marked with a cross, meaning no export support. For VMF, the Hammer format map source, both the import and export columns are marked as not planned. The one-line summary is that SourceIO reads finished game assets so you can work with them in Blender, and it does not write them back. If your workflow ends with a file that has to load in the game engine, this tool is a step in the middle of the pipeline rather than the end of it. The tables are labelled as covering version 5.3.0, so check the current release before assuming a format has gained support since then.

## Source 2 formats import, and the tables show where the gaps are

The Source 2 table mirrors the Source 1 one with different extensions. VMDL models import, VMAP compiled maps import, VTEX textures import, and VMAT materials import. Again, the export column is a cross for the texture and material rows and not planned for the model and map rows, and the second VMAP row, the Hammer format, is not planned in either direction. Two of the three named map related gaps are therefore deliberate rather than accidental, since a compiled VMAP is binary and a Hammer VMAP is a text format that the project has simply not taken on. The credits section names ValveResourceFormat as the source of initial research on the Source 2 file formats, and HFSExtract as the HFS extractor that was used to write a native decryptor, which is a fair indication of how much of the Source 2 work involves binary structures and decryption rather than plain asset parsing.

## Game support is uneven, and the table says exactly where

The supported games table lists what each title actually gets, and the differences are informative. Full support is claimed for TF2, Source FilmMaker, Garry's Mod, HL2 and episodes, Portal 1 and 2, L4D2 with the note that you should expect infected materials, and BlackMesa. Partial support is listed for CSGO with models, maps but not all entities, textures, and materials, and the same shape of limitation for Vindictus, Titanfall 1, Half-Life: Alyx, and Aperture Desk Job, where the materials caveat expands to not all shaders. Counter Strike 2 is partial with the same limits plus the Blender version note. S&BOX is partial and described as waiting for full release. The recurring theme is maps, where entity coverage is incomplete. If your work depends on every brush, trigger, or entity in a level being present, the table is the place to check rather than the feature list at the top of the README.

## The addon borrows from several other projects

SourceIO stands on other people's work, and the README credits it explicitly. The datamodel.py file comes from Artfunkel's BlenderSourceTools, ValveResourceFormat provided the initial research into Source 2 file formats, the BlenderVertexLitGeneric shader nodegroup is by syborg64, the equilib cubemap to equirectangular converter is by haruishi43, and the HFS extractor used to write the native decryptor is from yretenai. There is also a note crediting hisanimations for the idea behind better HWM expression handling. Two of these carry licensing implications worth checking before you ship anything. The datamodel file and the shader nodegroup are copied into a repository distributed under the MIT licence, so redistribution of the addon carries those upstream terms with it. The README does not restate the terms of the credited projects, so if you plan to redistribute the addon rather than use it yourself, read the licences of the specific files you depend on.

## MIT licensed, with frequent releases and a visible TODO list

The repository carries a LICENSE file and the project is MIT licensed, which permits commercial use, modification, and redistribution provided the notice is kept. Release activity is regular by the standards of addons: 5.5.4 on 2026-08-03, 5.5.3 on 2026-04-08 with the note that it fixes MDL V44 flex import, and 5.5.2 on 2026-02-03 with CS2 bugfixes. The last push to the repository was on 2026-10-13. The structure of the repository supports that cadence, with a tests directory, a wiki directory, a TODO.md at the top level that the README links as the current task list, and separate code for logging. Two caveats on adoption. First, the version numbering is well past the point where the format tables in the README, labelled as version 5.3.0, reflect the current state, so the wiki and TODO file are the better reference for what a given release handles. Second, the homepage is a Discord invite rather than a documentation site, so the community support channel and the project documentation are two different places, and the wiki is the one to read.

## Conclusion

SourceIO is worth adopting if you need to pull Source engine models, maps, textures, or materials into Blender for study, remix, or animation, and you are working in the Source 1 or Source 2 formats it lists as supported. It is the wrong tool if you need to write assets back out for a game, since every export column in the format tables is marked as not supported or not planned. Before you install, confirm your Blender version is supported by the release you download, read the TODO.md list for the formats that are still outstanding, and check the supported games table for your title, since CSGO, Vindictus, Titanfall 1, Counter Strike 2, Half-Life: Alyx, S&BOX, and Aperture Desk Job are all listed as partial support.

## FAQ

### How do I open the SourceIO import tools in Blender?

Go to File, then Import, then Source Engine Assets, according to the README. The addon registers itself in that menu once it is installed.

### Can SourceIO export assets back to a Source engine game?

No. In the format tables the export column is marked as unsupported for MDL, VTF, VMT, VMDL, VTEX, and VMAT, and VMF, Hammer format VMAP, and BSP export are marked as not planned.

### Which games does SourceIO support fully?

The supported games table lists full support for TF2, Source FilmMaker, Garry's Mod, HL2 and episodes, Portal 1 and 2, L4D2 with the note that you should expect infected materials, and BlackMesa. Other titles are listed as partial.

### What Blender version does SourceIO need?

The README badge states Blender 4.5 or newer while the project description says Blender 4.0 or later. The Counter Strike 2 row notes that it requires Blender 3.4 or newer, so check the release you download.

## Sources

- [License: MIT](https://github.com/REDxEYE/SourceIO/blob/master/LICENSE)
- [Project website](https://discord.gg/XJvhzaXZf3)
- [README](https://github.com/REDxEYE/SourceIO/blob/master/README.md)
- [REDxEYE/SourceIO on GitHub](https://github.com/REDxEYE/SourceIO)
- [Releases](https://github.com/REDxEYE/SourceIO/releases)

---

Hysen Labs editorial analysis, written from the project's own repository and release notes. Cite the canonical page: https://hysenlabs.com/projects/redxeye-sourceio