Cobalt marker example

Replaces all six floor-indicator GLBs with textured cobalt housings and additional hexagonal fasteners. Gameplay-colored MarkerSignal surfaces stay controlled by the game. Enable the mod and restart, then hover a tower, use the factory cursor and press T with radar unlocked.

See MARKERS.md for dimensions, axes, reserved material names, range behavior and export instructions. Models/Markers/*.glb are self-contained and editable in Blender. No scripts, external textures or .import files needed.

Generated by tools/art/marker_blender_sources.py; vanilla is still the default.