Message generation layer
The message generation layer turns the path network and Destination Dictionary into the messages shown on signs. It considers the sign type, sign position, sign rotation, bound target points, destination groups, and manual message choices.
Key considerations
A target point must be bound to a destination before it can produce a destination-backed automatic route message.
Direction signs use the first walking direction from the decision point to decide which face or direction should show a destination. Fingerpost signs assign destinations to direction sectors and then apply both per-direction and whole-sign message limits.
Navigation signs can show broader grouped destination messages when that produces a clearer directory.
Identification signs use the destination message bound to the target point.
Destination groups can collapse several destinations into one broader message, then expand again as the visitor gets closer.
Sign type capacity controls how many automatic messages can stay selected on a face or sign.
Manual messages can coexist with generated messages. When automatic messages regenerate, WFP preserves compatible manual selection changes where possible.
Message selection via group memberships
Group memberships tell WFP when several individual destinations may be represented by one destination-group message. The planner still starts from reachable target points bound to destination entries. Memberships then give WFP a second choice: keep the individual destination messages, or replace a set of related destinations with their group message when that is clearer and still accurate.
A destination can belong to one or more groups. Group settings affect both the individual destination candidates and the possible group message:
Group message provides the text or number shown when the group is selected instead of its members.
Group signing distance can limit both the group message and its member destinations.
Group priority weight can raise the effective priority of member destinations during selection.
Expand distance can keep members visible while the sign is close to them, then allow the group to collapse farther away.
Ambiguity behavior can keep a group collapsed when its members require different first-hop walking directions from a decision point.
WFP only selects a group message when the group can cover the relevant member destinations for that sign context. A group normally needs at least two reachable member destinations before it is useful as a replacement. If only one member is relevant, WFP keeps the individual destination message.
For Direction signs, WFP avoids grouped messages that would point visitors the wrong way. If the members of a group require different first walking directions from the sign, WFP keeps them expanded unless the group's ambiguity settings and the sign context allow a broader message. Navigation signs can use broader group messages more often because they present a directory rather than a single directional instruction.
When groups are nested, WFP considers the more specific groups before broader groups. For example, a Gates A group may be selected before a wider Gates group if that gives a better message for the current sign. If a group is inactive, WFP leaves its member destinations available, but it does not use that group for automatic collapse or capacity merge.
Group memberships also affect overflow handling. If too many automatic messages are selected for a sign face, WFP can try another group selection pass and replace several member messages with a suitable group message before moving lower-retention messages to overflow.
Message selection algorithm parameters
WFP provides project defaults and per-decision-point settings for two parts of the message selection algorithm. Best-route pruning is enabled by default. Message aggregation guard is disabled by default. New decision points, and path points converted to decision points, copy the current project defaults at the time they are created or converted.
Open Project → Project Properties... to edit the project defaults:
Best-route pruning → Keep only the shortest route per target
Message aggregation guard → Sync destination groups expansion across signs
Each option also provides Reset all decision points, which applies the current project default to every existing decision point.
To override either of these parameters for a single decision point, right-click that decision point in the Level View and edit its Route candidates and Message aggregation guard settings.
Best-route pruning
Best-route pruning controls how route candidates are pruned before messages are assigned to signs.
When enabled, WFP keeps only the shortest route to each reachable target from the decision point. This keeps message selection stable in networks where the same destination can be reached through loops.
When disabled for a decision point, WFP keeps multiple route candidates to the same target when available. This can be useful when you intentionally want alternate routes to remain available for direction-sensitive signs, typically for further manual selection or de-selection on a sign face. Keep in mind that this can also make the same destination eligible through more than one initial direction.
Message aggregation guard
The Message aggregation guard can be useful in certain projects, depending on the topology and complexity of the path network. Its applicability should be evaluated on a case-by-case basis.
The Message aggregation guard controls whether Direction signs at the same decision point coordinate expansion and collapse behavior for shared destination groups. Because the project default is disabled, Direction signs normally aggregate group messages independently unless the guard is enabled globally or for a specific decision point.
When enabled, WFP checks the Direction signs attached to the decision point before collapsing a destination group. If the same group would require different initial walking directions across those signs, WFP keeps the group expanded and prevents capacity re-aggregation from collapsing it. This avoids broad group messages that could direct visitors incorrectly or cause sibling signs to disagree about the same group.
When disabled for a decision point, each Direction sign can aggregate group messages more independently. Broader group messages may appear more often, but shared destination groups may expand on one sign and collapse on another when their route context differs.
Sign Face Capacity Packaging
Sign face capacity packaging uses the capacity parameters set in the sign type.
During generation, selected manual messages reserve capacity before automatic messages are packed. WFP then plans the automatic messages for each face, applies destination groups and progressive disclosure, and checks whether the selected automatic messages fit the current capacity pass.
If there are too many automatic messages, WFP tries to re-aggregate them into suitable destination-group messages. This can replace several individual destinations with one broader group message when the group is active, covers the same destinations, and would not create misleading directional guidance. Direction signs are stricter here: a capacity merge is only allowed when the grouped destinations share the same first walking direction.
If the sign type allows flexible capacity, WFP may repeat the planning pass with a larger capacity value. Each pass may produce a different grouping choice because the planner re-checks disclosure, group merge candidates, and message retention against the new capacity.
If the last allowed pass still has too many automatic messages, the lower-retention messages become overflow messages. Overflow messages stay available for review in schedules and inspectors, but their selection flag is off.
For Fingerpost signs, WFP first applies the per-direction capacity to each virtual face. It then applies the whole-sign capacity across all directions and moves the remaining lower-retention automatic messages to overflow without rerunning disclosure.