Knowledge belongs to a place: what this world knows is what a pad here can aim at

src/main/java/zmaster587/advancedRocketry/command/test/TestProbeCommand.java

@@ -2540,14 +2540,57 @@ private void handleTelescope(MinecraftServer server, ICommandSender sender, Stri
                     zmaster587.advancedRocketry.api.AdvancedRocketryItems.itemMemoryCrystal);
             // A deliberately BLANK crystal: the starter addresses would make every count a test
             // asserts depend on the world's planet list rather than on what the scan resolved.
-            zmaster587.advancedRocketry.item.ItemMemoryCrystal.writeMemory(stack,
-                    new zmaster587.advancedRocketry.navigation.CrystalMemory());
+            zmaster587.advancedRocketry.navigation.CrystalMemory seeded =
+                    new zmaster587.advancedRocketry.navigation.CrystalMemory();
+            // ...unless a caller names ONE world it must hold. A test that needs the deposit to be
+            // the only possible source of a piece of knowledge cannot use a crystal the survey
+            // filled, because the survey teaches this world as it goes.
+            if (args.length >= 6) {
+                int namedDim = parseIntOr(args[5], zmaster587.advancedRocketry.api.Constants.INVALID_PLANET);
+                if (namedDim != zmaster587.advancedRocketry.api.Constants.INVALID_PLANET) {
+                    seeded.record(new zmaster587.advancedRocketry.navigation.CrystalEntry(
+                            zmaster587.advancedRocketry.space.GalacticCoord.ofSectorLocal(
+                                    7000L, 0L, 0L, 0L, 0L, 0L),
+                            "probe-named-" + namedDim,
+                            zmaster587.advancedRocketry.universe.SystemBodyKind.PLANET,
+                            zmaster587.advancedRocketry.universe.InfoTier.TELESCOPE, 1L, namedDim));
+                }
+            }
+            zmaster587.advancedRocketry.item.ItemMemoryCrystal.writeMemory(stack, seeded);
             scope.setInventorySlotContents(
                     zmaster587.advancedRocketry.tile.multiblock.TileObservatory.SLOT_CRYSTAL, stack);
             send(sender, "{\"ok\":true,\"addresses\":" + crystalAddresses(scope) + "}");
             return;
         }
 
+        if ("deposit".equalsIgnoreCase(verb)) {
+            // The Deposit button's own path: read the crystal in the machine into what THIS world
+            // knows. Reported as landed/total because an address of a world nobody has landed on has
+            // nothing for tier-1 to fly to and is skipped.
+            java.util.List<Integer> before = new java.util.ArrayList<>();
+            for (zmaster587.advancedRocketry.navigation.CrystalEntry entry
+                    : zmaster587.advancedRocketry.item.ItemMemoryCrystal.memoryOf(
+                            scope.getStackInSlot(
+                                    zmaster587.advancedRocketry.tile.multiblock.TileObservatory
+                                            .SLOT_CRYSTAL)).list()) {
+                if (entry.namesBody()) {
+                    before.add(entry.dimId());
+                }
+            }
+            int[] result = scope.uploadCrystalHere();
+            StringBuilder dims = new StringBuilder("[");
+            for (int i = 0; i < before.size(); i++) {
+                if (i > 0) dims.append(',');
+                dims.append(before.get(i));
+            }
+            dims.append(']');
+            // The dims are reported, not just the count: a test that could only read "3 landed" would
+            // have to guess WHICH worlds a pad here may now be aimed at.
+            send(sender, "{\"ok\":true,\"landed\":" + result[0] + ",\"total\":" + result[1]
+                    + ",\"dims\":" + dims + "}");
+            return;
+        }
+
         if ("abort".equalsIgnoreCase(verb)) {
             boolean stopped = scope.abortRegionScan();
             send(sender, "{\"ok\":" + stopped + telescopeScanFields(scope, scope.getActiveScan(), world) + "}");
@@ -2630,6 +2673,10 @@ private String telescopeScanFields(zmaster587.advancedRocketry.tile.multiblock.T
                 .append(",\"origin\":").append(origin == null ? "null" : "\"" + origin.cellKey() + "\"")
                 .append(",\"scanning\":").append(scan != null)
                 .append(",\"addresses\":").append(crystalAddresses(scope))
+                // WHICH worlds the crystal holds, read without touching anything. A test that had to
+                // call `deposit` to find out would have deposited them, and could no longer show
+                // that pressing the button is what teaches this world.
+                .append(",\"crystalDims\":").append(crystalDims(scope))
                 .append(",\"lastDiscoveries\":").append(scope.getLastScanDiscoveries())
                 // Where the OPERATOR has the instrument pointed — the tile's own pick, which is what
                 // a GUI click changes and what the next scan will use. Distinct from the region a
@@ -2694,6 +2741,29 @@ private int crystalAddresses(zmaster587.advancedRocketry.tile.multiblock.TileObs
         return zmaster587.advancedRocketry.item.ItemMemoryCrystal.memoryOf(stack).size();
     }
 
+    /** The dimensions the crystal in that slot names, as a JSON array. Reads nothing into anything. */
+    private String crystalDims(zmaster587.advancedRocketry.tile.multiblock.TileObservatory scope) {
+        net.minecraft.item.ItemStack stack = scope.getStackInSlot(
+                zmaster587.advancedRocketry.tile.multiblock.TileObservatory.SLOT_CRYSTAL);
+        if (!zmaster587.advancedRocketry.item.ItemMemoryCrystal.isCrystal(stack)) {
+            return "[]";
+        }
+        StringBuilder out = new StringBuilder("[");
+        boolean first = true;
+        for (zmaster587.advancedRocketry.navigation.CrystalEntry entry
+                : zmaster587.advancedRocketry.item.ItemMemoryCrystal.memoryOf(stack).list()) {
+            if (!entry.namesBody()) {
+                continue;
+            }
+            if (!first) {
+                out.append(',');
+            }
+            out.append(entry.dimId());
+            first = false;
+        }
+        return out.append(']').toString();
+    }
+
     private zmaster587.advancedRocketry.tile.multiblock.TileObservatory observatoryAt(
             net.minecraft.world.World world, BlockPos pos) {
         net.minecraft.tileentity.TileEntity te = world.getTileEntity(pos);
@@ -5230,7 +5300,21 @@ private void handleSpace(MinecraftServer server, ICommandSender sender, String[]
                     zmaster587.advancedRocketry.space.GalacticCoord.ofSectorLocal(
                             parseIntOr(args[1], 0), parseIntOr(args[2], 0), parseIntOr(args[3], 0),
                             0L, 0L, 0L);
-            int dimId = zmaster587.advancedRocketry.universe.PlanetRealizer.realize(server, cell);
+            // A cell names a family - a planet and the moons that share its address - so the probe
+            // states WHICH of them it means. Default 0, the planet, with an optional variant arg;
+            // a caller that wants the moon has to say so, exactly as a descent does.
+            int variant = args.length >= 5 ? parseIntOr(args[4], 0) : 0;
+            java.util.List<zmaster587.advancedRocketry.universe.SystemBody> family =
+                    zmaster587.advancedRocketry.universe.UniverseRegistry.get(server) == null
+                            ? java.util.Collections.<zmaster587.advancedRocketry.universe.SystemBody>emptyList()
+                            : zmaster587.advancedRocketry.universe.UniverseRegistry.get(server)
+                                    .realizableBodiesAt(cell);
+            if (variant < 0 || variant >= family.size()) {
+                send(sender, "{\"ok\":false,\"reason\":\"no body with that variant in the cell\"}");
+                return;
+            }
+            int dimId = zmaster587.advancedRocketry.universe.PlanetRealizer.realize(server,
+                    family.get(variant));
             if (dimId == zmaster587.advancedRocketry.api.Constants.INVALID_PLANET) {
                 send(sender, "{\"ok\":false,\"reason\":\"nothing landable in that cell\"}");
                 return;
@@ -5993,6 +6077,36 @@ private void handleDim(ICommandSender sender, String[] args) {
     // Planet/weather probes ----------------------------------------------
 
     private void handlePlanet(ICommandSender sender, String[] args) {
+        // What a TIER-1 launch pad standing on one world may be aimed at, asked of the production
+        // gate rather than re-derived here: a real rocket in the standing world answers
+        // IPlanetDefiner.isPlanetKnown, and the two halves are reported beside it so a red test says
+        // WHICH of them moved - the pack's floor or what this body has learned.
+        if (args.length >= 3 && "knowledge".equalsIgnoreCase(args[0])) {
+            int standingDim = parseIntOr(args[1], Integer.MIN_VALUE);
+            int targetDim = parseIntOr(args[2], Integer.MIN_VALUE);
+            net.minecraft.world.World here = net.minecraftforge.common.DimensionManager
+                    .getWorld(standingDim);
+            DimensionProperties target = DimensionManager.getInstance()
+                    .getDimensionPropertiesOrNull(targetDim);
+            DimensionProperties standing = DimensionManager.getInstance()
+                    .getDimensionPropertiesOrNull(standingDim);
+            if (here == null || target == null) {
+                send(sender, "{\"error\":\"standing world not loaded or unknown target\"}");
+                return;
+            }
+            zmaster587.advancedRocketry.entity.EntityRocket rocket =
+                    new zmaster587.advancedRocketry.entity.EntityRocket(here);
+            send(sender, "{\"standing\":" + standingDim + ",\"target\":" + targetDim
+                    + ",\"known\":" + rocket.isPlanetKnown(target)
+                    + ",\"global\":" + DimensionManager.getInstance().isPlanetKnown(targetDim)
+                    + ",\"local\":" + (standing != null && standing.isPlanetKnownHere(targetDim))
+                    + ",\"research\":"
+                    + zmaster587.advancedRocketry.api.ARConfiguration.getCurrentConfig()
+                            .planetsMustBeDiscovered
+                    + "}");
+            return;
+        }
+
         if (args.length >= 2 && "info".equalsIgnoreCase(args[0])) {
             int dim = parseIntOr(args[1], Integer.MIN_VALUE);
             DimensionProperties props = DimensionManager.getInstance().getDimensionProperties(dim);

src/main/java/zmaster587/advancedRocketry/dimension/DimensionProperties.java

@@ -767,11 +767,64 @@ public void setHasRings(boolean value) {
     //Adds a beacon location to the planet's surface
     public void addBeaconLocation(World world, HashedBlockPosition pos) {
         beaconLocations.add(pos);
-        DimensionManager.getInstance().knownPlanets.add(getId());
 
         //LAAZZY
-        if (!world.isRemote)
+        if (!world.isRemote) {
+            for (DimensionProperties taught : teachOwnSystem()) {
+                PacketHandler.sendToAll(new PacketDimInfo(taught.getId(), taught));
+            }
             PacketHandler.sendToAll(new PacketDimInfo(getId(), this));
+        }
+    }
+
+    /**
+     * Tell the bodies of this body's own system that this place exists, and return the ones that
+     * did not already know.
+     *
+     * <p><b>A beacon is a local announcement, not a galactic one.</b> It used to add this planet to
+     * the GLOBAL known-set, so planting one anywhere made the place selectable from every launch pad
+     * in the game. What is true is narrower and more interesting: the neighbours know, because they
+     * can see it. So the beacon writes into the known-set of every body of its own system, and
+     * nothing outside that system learns anything.</p>
+     *
+     * <p>It can never be the thing that first reveals a place - a beacon is planted by hand, so
+     * somebody already flew here, which means the destination was already reachable. That is why
+     * scoping it costs nothing: a beacon spreads knowledge inside reach and never creates reach.</p>
+     */
+    public List<DimensionProperties> teachOwnSystem() {
+        List<DimensionProperties> taught = new ArrayList<>();
+        discoverPlanet(getId()); // the body it stands on, always - the degenerate system of one
+        StellarBody star = getStar();
+        if (star == null) {
+            return taught; // a world with no star of its own: the beacon teaches only its own ground
+        }
+        for (IDimensionProperties sibling : star.getPlanets()) {
+            DimensionProperties props = DimensionManager.getInstance()
+                    .getDimensionPropertiesOrNull(sibling.getId());
+            if (props == null) {
+                continue;
+            }
+            teach(props, taught);
+            // A moon is a child of its planet rather than of the star, so the star's list alone
+            // would leave every moon of the system ignorant of a beacon in it.
+            for (int childId : props.getChildPlanets()) {
+                DimensionProperties child = DimensionManager.getInstance()
+                        .getDimensionPropertiesOrNull(childId);
+                if (child != null) {
+                    teach(child, taught);
+                }
+            }
+        }
+        return taught;
+    }
+
+    /** Teach {@code body} about this place, collecting it when that changed anything. */
+    private void teach(DimensionProperties body, List<DimensionProperties> taught) {
+        if (body.getId() == getId() || body.isPlanetKnownHere(getId())) {
+            return;
+        }
+        body.discoverPlanet(getId());
+        taught.add(body);
     }
 
     public HashSet<HashedBlockPosition> getBeacons() {
@@ -1692,7 +1745,10 @@ private void readFromTechnicalNBT(NBTTagCompound nbt) {
                 int[] location = list.getIntArrayAt(i);
                 beaconLocations.add(new HashedBlockPosition(location[0], location[1], location[2]));
             }
-            DimensionManager.getInstance().knownPlanets.add(getId());
+            // No global add on load any more. What a beacon taught is held by the bodies it taught,
+            // in their own saved known-sets, so re-announcing this place to the whole game at every
+            // load would put back exactly the reach the scoping removed. A world whose beacons
+            // predate the local sets simply has nothing recorded - 3.0.0 carries no old saves.
         } else
             beaconLocations.clear();
 
@@ -1734,6 +1790,13 @@ public void readFromNBT(NBTTagCompound nbt) {
 
         NBTTagList list;
 
+        // Cleared first: this object is reused across loads, and a merge would make a body remember
+        // what a previous save taught it.
+        locallyKnownPlanets.clear();
+        for (int dimId : nbt.getIntArray("locallyKnownPlanets")) {
+            locallyKnownPlanets.add(dimId);
+        }
+
         if (nbt.hasKey("skyColor")) {
             list = nbt.getTagList("skyColor", NBT.TAG_FLOAT);
             skyColor = new float[list.tagCount()];
@@ -2197,9 +2260,50 @@ public void write_terraforming_data(NBTTagCompound nbt) {
 
 
     }
+    /**
+     * What is known ON this body: the planets a launch pad standing here may be aimed at, beyond the
+     * ones everybody knows.
+     *
+     * <p><b>Knowledge belongs to a place.</b> An observatory built here teaches THIS body; a beacon
+     * teaches the bodies of its own system; a memory crystal uploaded here deposits what somebody
+     * carried in. None of that reaches the global set, and none of it reaches a neighbouring world -
+     * a launch pad on a moon offers a different list than the pad on the planet below it.</p>
+     *
+     * <p>It is ADDITIVE over the global set rather than a replacement for it, so a pack that authors
+     * {@code <isKnown>} keeps authoring exactly as it did: the global set is the floor everyone
+     * stands on, this is what a particular world has learned since.</p>
+     *
+     * <p>Communal per world, not per player: two players on the same body see the same list.</p>
+     */
+    private final Set<Integer> locallyKnownPlanets = new HashSet<>();
+
+    /** Teach this body about {@code dimId}. Idempotent. */
+    public void discoverPlanet(int dimId) {
+        locallyKnownPlanets.add(dimId);
+    }
+
+    /** Whether THIS body knows {@code dimId} - the local half of the gate, with no global fallback. */
+    public boolean isPlanetKnownHere(int dimId) {
+        return locallyKnownPlanets.contains(dimId);
+    }
+
+    /** What this body knows, for readers that need the whole set (GUI, sync, tests). */
+    public Set<Integer> getLocallyKnownPlanets() {
+        return Collections.unmodifiableSet(locallyKnownPlanets);
+    }
+
     public void writeToNBT(NBTTagCompound nbt) {
         NBTTagList list;
 
+        if (!locallyKnownPlanets.isEmpty()) {
+            int[] known = new int[locallyKnownPlanets.size()];
+            int k = 0;
+            for (int dimId : locallyKnownPlanets) {
+                known[k++] = dimId;
+            }
+            nbt.setIntArray("locallyKnownPlanets", known);
+        }
+
         if (skyColor != null) {
             list = new NBTTagList();
             for (float f : skyColor) {

src/main/java/zmaster587/advancedRocketry/entity/EntityRocket.java

@@ -3852,7 +3852,20 @@ public LinkedList<IInfrastructure> getConnectedInfrastructure() {
 
     @Override
     public boolean isPlanetKnown(IDimensionProperties properties) {
-        return !ARConfiguration.getCurrentConfig().planetsMustBeDiscovered || DimensionManager.getInstance().isPlanetKnown(properties.getId());
+        if (!ARConfiguration.getCurrentConfig().planetsMustBeDiscovered) {
+            return true;
+        }
+        int target = properties.getId();
+        // The global set is the FLOOR - what a pack authored as known, plus dim 0. Everything past it
+        // is learned by a particular world, so the second question is asked of the body this rocket
+        // is standing on and not of the game.
+        if (DimensionManager.getInstance().isPlanetKnown(target)) {
+            return true;
+        }
+        DimensionProperties here = world == null
+                ? null
+                : DimensionManager.getInstance().getDimensionPropertiesOrNull(world.provider.getDimension());
+        return here != null && here.isPlanetKnownHere(target);
     }
 
     @Override

src/main/java/zmaster587/advancedRocketry/tile/TileAdvancedFlightComputer.java

@@ -594,8 +594,10 @@ public void update() {
                             // descend. The scan above must never allocate a dimension.
                             int targetDim = body.dimId();
                             if (targetDim == zmaster587.advancedRocketry.api.Constants.INVALID_PLANET) {
+                                // The BODY, not its cell: a moon shares its planet's address, so a
+                                // cell names a family and only the body says which of them was flown to.
                                 targetDim = zmaster587.advancedRocketry.universe.PlanetRealizer
-                                        .realize(server, body.name());
+                                        .realize(server, body);
                                 if (targetDim
                                         == zmaster587.advancedRocketry.api.Constants.INVALID_PLANET) {
                                     continue; // nothing landable here after all