Bitmap Overlay is a slider that blends an image over the generated relief, from fully hidden to fully superimposed, so you can rotate, zoom, and check how closely the two align. With Fidelity, it overlays your original source image directly onto the final relief — a genuine accuracy check. With Forge, it overlays the intermediate sculptural form Forge builds before applying its own interpretation, rather than your original source, so it’s available but less useful as a direct accuracy comparison.
