Some housekeeping and some editor tools for schedules anchors

Source/ProjectEleriEditor/Public/NpcScheduleActionCustomization.h

@@ -22,6 +22,20 @@ class SWidget;
  * an id that no actor in this level claims is left as it is, because that is a real state (furniture
  * that was deleted, or furniture sitting in a sublevel that is not loaded) and not something to hide.
  *
+ * Picking an anchor also records where that anchor stands, into the action's own AnchorTransform, so
+ * that a schedule still means something in a running world while the furniture it points at sits in a
+ * cell nobody has loaded. The panel is the only moment at which both halves can be had from the actor
+ * itself, which is why the two fields that snapshot is stored in are written here and, being written
+ * rather than authored, keep no row anything could be typed into.
+ *
+ * What that record needs is not another field to fill in but a way to see that it has gone stale, so
+ * the panel reports it in a read-only row of its own, Anchor Location, directly under the anchor it
+ * belongs to. The row stands the recorded place against where the anchor stands now and says so when
+ * the two have come apart. It reads the same whole-transform rule as Schedule Asset Recheck, so the
+ * row and the sweep can never disagree about which schedules have drifted, and it is the sweep - or
+ * picking the anchor again - that clears the marker. The two fields themselves are still reported
+ * through the anchor row's tooltip.
+ *
  * Every other member of the struct keeps the row the details panel would have given it.
  */
 class FNpcScheduleActionCustomization : public IPropertyTypeCustomization
@@ -39,6 +53,13 @@ protected:
 	 *  unassign button. Stands in for the raw Guid field, which is never shown. */
 	void AddAnchorRow(IDetailChildrenBuilder& ChildBuilder, TSharedRef<IPropertyHandle> AnchorHandle) const;
 
+	/** The anchor location row: the place this action kept for its anchor, read back out of the
+	 *  snapshot the pick wrote and stood against where that anchor stands now, directly under the anchor
+	 *  row it belongs to. Read only on purpose rather than a disabled copy of the rows above it: the
+	 *  record is written by picking an anchor and by Recheck Schedules, and a row that let it be typed
+	 *  in would be a third writer able to send an NPC anywhere at all. */
+	void AddAnchorLocationRow(IDetailChildrenBuilder& ChildBuilder, TSharedRef<IPropertyHandle> AnchorHandle) const;
+
 	/** What the id points at: the actor's label, "None" when nothing is assigned, or the raw id when no
 	 *  actor in this level claims it. */
 	FText GetAnchorText(TSharedRef<IPropertyHandle> AnchorHandle) const;
@@ -51,6 +72,48 @@ protected:
 	 *  glance from one whose anchor the panel cannot name. */
 	FSlateColor GetAnchorColor(TSharedRef<IPropertyHandle> AnchorHandle) const;
 
+	/** The recorded place, in whichever state the row is actually in: "None" for an action with no
+	 *  anchor, "Not recorded" for an anchor picked before there was anywhere to record one, and the
+	 *  recorded point itself, marked "(differs)" once the anchor has moved away from it. */
+	FText GetAnchorLocationText(TSharedRef<IPropertyHandle> AnchorHandle) const;
+
+	/** What the row is reporting and what to do when it reports a difference. Written per state, the
+	 *  way the anchor row's tooltip is, so that an action agreeing with its anchor is not handed
+	 *  instructions it has no use for. */
+	FText GetAnchorLocationTooltip(TSharedRef<IPropertyHandle> AnchorHandle) const;
+
+	/** Warning while the record and the anchor disagree, subdued while there is no record at all, and
+	 *  ordinary foreground otherwise - a record this level cannot check included, since a schedule for
+	 *  a cell nobody has loaded is exactly what the record is for. */
+	FSlateColor GetAnchorLocationColor(TSharedRef<IPropertyHandle> AnchorHandle) const;
+
+	/** How the recorded place stands against the anchor itself. One answer worked out in one place,
+	 *  because three of the members above are each asked for it: a row whose text said "(differs)"
+	 *  while its colour said otherwise would be two readings of one rule, and the rule itself is
+	 *  already shared with Schedule Asset Recheck by hand. */
+	enum class EAnchorLocationState : uint8
+	{
+		/** No anchor at all, so there is no place to record and nothing to compare. */
+		NoAnchor,
+
+		/** An anchor, but no place recorded for it: a pick made before there was anywhere to store one,
+		 *  which is the state every action authored before snapshots existed is in. */
+		NotRecorded,
+
+		/** A place recorded, and no actor in this level claims the anchor's id to check it against. */
+		Unresolved,
+
+		/** A place recorded that still matches where the anchor stands. */
+		UpToDate,
+
+		/** A place recorded that the anchor has since moved away from, whole transform and all. */
+		Differs
+	};
+
+	/** Which of those states this action is in, with the two transforms it was decided from handed back
+	 *  as well, since every caller has something to say about one or both of them. */
+	EAnchorLocationState GetAnchorLocationState(TSharedRef<IPropertyHandle> AnchorHandle, TOptional<FTransform>& OutSnapshot, FTransform& OutLiveTransform) const;
+
 	bool CanClearAnchor(TSharedRef<IPropertyHandle> AnchorHandle) const;
 
 	/** Writes one id into the action. An invalid id is what unassign does, so the button that clears
@@ -66,6 +129,32 @@ protected:
 	 *  value and so comes back as unassigned. */
 	static FGuid ReadAnchorGuid(const TSharedRef<IPropertyHandle>& AnchorHandle);
 
+	/** A field of the action the anchor handle belongs to, reached from the anchor handle rather than
+	 *  handed around: the widgets that hold the anchor handle outlive the layout call that built them,
+	 *  and a sibling looked up at the moment it is written is exactly as fresh as the anchor itself.
+	 *  Null when the handle is not a child of a struct node, or when the struct has no such field, and
+	 *  that is not a failure: the anchor is then assigned without a snapshot, which is the state every
+	 *  schedule authored before snapshots existed is in. */
+	static TSharedPtr<IPropertyHandle> GetAnchorSibling(const TSharedRef<IPropertyHandle>& AnchorHandle, FName ChildName);
+
+	/** Where the actor an id belongs to is standing, answered through the rule the game reads
+	 *  (EleriStandPoint::ResolveAnchorTransform) rather than through the actor's own transform, so that
+	 *  a schedule saved in the editor and one resolved in a running world cannot put the same NPC in
+	 *  two different places. False when no actor in this level claims the id, which is what clearing
+	 *  the anchor leaves behind and what assigning an anchor whose sublevel is not loaded leaves
+	 *  behind. */
+	static bool ResolveAnchorSnapshot(const FGuid& AnchorGuid, FTransform& OutTransform);
+
+	/** The place this action has kept for its anchor, if it kept one. Nothing when no snapshot was ever
+	 *  stored, when those fields are not part of the struct, or when the row stands for several actions
+	 *  at once, since several actions have no one place between them to report. */
+	TOptional<FTransform> GetCachedAnchorTransform(const TSharedRef<IPropertyHandle>& AnchorHandle) const;
+
+	/** Writes the snapshot that goes with an id. Raw data rather than a formatted string, because a
+	 *  transform has no text import to round trip through and this is the only way one reaches the
+	 *  asset. */
+	static void WriteCachedAnchorTransform(const TSharedRef<IPropertyHandle>& AnchorTransformHandle, const FTransform& Snapshot);
+
 	/** The first actor in the current selection that can be an anchor, or null when there is none. */
 	static AActor* GetSelectedAnchorActor();