Two Geometries, Never Merged

"The route you meant to take and the route you actually took are two different truths. Never let one erase the other."

Two Routes, Two Layers

On the journey map, every movement can exist twice: as planned geometry (the route you intended) and as actual geometry (the route you really traveled). Waystone keeps these as separate layers, and the rule is absolute — one must never overwrite the other. When you actually take a detour, the app does not quietly update "the route" to match reality and forget you ever meant something else. It records the actual path on its own layer and leaves the plan intact underneath.

Because the Gap Is the Point

Why bother keeping both? Because the entire value of a travel-memory engine lives in the gap between them. "We planned to summit but the weather turned, so we stayed in the valley" is not noise to be cleaned up — it is one of the most important things a trip teaches. If actual silently overwrites planned, that lesson vanishes, and next year you cannot ask "which places did I plan but skip, and why?" — the question this engine exists to answer. Merging the two geometries would be optimizing for a tidy-looking map at the cost of the memory the map is supposed to hold.

The Same Rule, Everywhere

This is the geographic face of a principle that runs through the whole engine and gets its own track next: plan, revision, actual, and reflection are preserved separately. The map is just where that separation becomes visible. A planned route drawn in one style and an actual route drawn in another, side by side, is planned-versus-actual made literal — you can see the difference between intention and event. An engine that collapses them has thrown away the comparison, and the comparison was the reason to build it.

Code

Two layers, never collapsed·text

PLANNED layer   Interlaken --> Kleine Scheidegg --> summit
                (what Dad intended)

ACTUAL layer    Interlaken --> Kleine Scheidegg --> back down
                (fog; summit skipped)

# Rendered as two layers, side by side:
#   the plan stays visible, the detour is recorded,
#   and the GAP between them is a lesson for trip five.
#
# Wrong: overwrite planned with actual -> tidy map, lost memory.
# Right: keep both -> 'what did I skip, and why?' is answerable.

Exercise

Recall a trip where the real route diverged from the plan — a cancelled leg, a spontaneous detour, a skipped stop. Now check: does any record you kept still show BOTH the plan and what actually happened, or did the plan quietly get overwritten by reality? If the plan is gone, you lost the ability to learn from the divergence.

Hint

The test is whether you can still answer 'what did we mean to do here?' after the trip. If your notes only show what happened, they optimized for a clean record and threw away the comparison — which is the part that makes next year's plan smarter.