An open-source app for importing maps and models from the Source 1 engine, archived here for safekeeping. To use:

*Requirements*
- Blender 3.6 for DAE export
- Blender 5.1 for Plumber
- Plumber addon for Blender 5.1
- Hammer Editor

*Instructions*
1. Make a simple box room in Hammer Editor using the clipping tool, orient on base player sizes.
2. Open Blender 5.1 with Plumber addon installed.
3. Import the .VMF file of your box room.
4. Replace every material texture with texture files in your map project folder.
5. Export file to .obj.
6. Open Blender 3.6.
7. Import .obj file.
8. Change the object/or multiple objects' size from 1.0 to 25.0 in all dimensions.
9. Triangulate object to remove polygons with more than 4 vertices, and then use "tris to quads" option to bring back normal quads in the geometry, because this creates more optimized geometry than leaving it as triangles.
10. Select your map mesh.
11. Export to Collada (.dae); in the export dialog, enable the setting Main > Selection Only and disable the setting Geom > Triangulate.