fixed disappearing markers (webbukkit#2533), many thanks to tiagoad

DynmapCore/src/main/java/org/dynmap/common/DynmapServerInterface.java

@@ -178,6 +178,17 @@ public abstract class DynmapServerInterface {
      * @return block ID, or -1 if chunk at given coordinate isn't loaded
      */
     public abstract int getBlockIDAt(String wname, int x, int y, int z);
+
+    /**
+     * Checks if a sign is at a given coordinate in a given world (if chunk is loaded)
+     * @param wname - world name
+     * @param x - X coordinate
+     * @param y - Y coordinate
+     * @param z - Z coordinate
+     * @return 1 if a sign is at the location, 0 if it's not, -1 if the chunk isn't loaded
+     */
+    public abstract int isSignAt(String wname, int x, int y, int z);
+
     /**
      * Get current TPS for server (20.0 is nominal)
      * @return ticks per second

DynmapCore/src/main/java/org/dynmap/markers/impl/MarkerSignManager.java

@@ -20,9 +20,6 @@ public class MarkerSignManager {
     private static DynmapCore plugin = null;
     private static String defSignSet = null;
           
-    private static final int SIGNPOST_ID = 63;
-    private static final int WALLSIGN_ID = 68;
-        
     private static class SignRec {
         String wname;
         int x, y, z;
@@ -143,14 +140,13 @@ public class MarkerSignManager {
             for(Iterator<Entry<String, SignRec>> iter = sign_cache.entrySet().iterator(); iter.hasNext(); ) {
                 Entry<String, SignRec> ent = iter.next();
                 SignRec r = ent.getValue();
-                /* If deleted marker, remote */
+                /* If deleted marker, remove */
                 if(r.m.getMarkerSet() == null) {
                     iter.remove();
                 }
                 else {
-                    /* Get block ID */
+                    if(plugin.getServer().isSignAt(r.wname, r.x, r.y, r.z) == 0) {
-                    int blkid = plugin.getServer().getBlockIDAt(r.wname, r.x, r.y, r.z);
+                        System.out.println("Removing from cache sign " + r.m.getLabel());
-                    if((blkid >= 0) && (blkid != WALLSIGN_ID) && (blkid != SIGNPOST_ID)) {
                         r.m.deleteMarker();
                         iter.remove();
                     }                    

forge-1.10.2/src/main/java/org/dynmap/forge_1_10_2/DynmapPlugin.java

@@ -146,6 +146,9 @@ public class DynmapPlugin
     private boolean useSaveFolder = true;
     private Field displayName = null; // MCPC+ display name
 
+    private static final int SIGNPOST_ID = 63;
+    private static final int WALLSIGN_ID = 68;
+
     private static final String[] TRIGGER_DEFAULTS = { "blockupdate", "chunkpopulate", "chunkgenerate" };
 
     private static final Pattern patternControlCode = Pattern.compile("(?i)\\u00A7[0-9A-FK-OR]");
@@ -510,6 +513,20 @@ public class DynmapPlugin
             return -1;
         }
 
+        @Override
+        public int isSignAt(String wname, int x, int y, int z) {
+            int blkid = this.getBlockIDAt(wname, x, y, z);
+
+            if (blkid == -1)
+                return -1;
+
+            if((blkid == WALLSIGN_ID) || (blkid == SIGNPOST_ID)) {
+                return 1;
+            } else {
+                return 0;
+            }
+        }
+
         @Override
         public void scheduleServerTask(Runnable run, long delay)
         {

forge-1.11.2/src/main/java/org/dynmap/forge_1_11_2/DynmapPlugin.java

@@ -146,6 +146,9 @@ public class DynmapPlugin
     private boolean useSaveFolder = true;
     private Field displayName = null; // MCPC+ display name
 
+    private static final int SIGNPOST_ID = 63;
+    private static final int WALLSIGN_ID = 68;
+
     private static final String[] TRIGGER_DEFAULTS = { "blockupdate", "chunkpopulate", "chunkgenerate" };
 
     private static final Pattern patternControlCode = Pattern.compile("(?i)\\u00A7[0-9A-FK-OR]");
@@ -518,6 +521,20 @@ public class DynmapPlugin
             return -1;
         }
 
+        @Override
+        public int isSignAt(String wname, int x, int y, int z) {
+            int blkid = this.getBlockIDAt(wname, x, y, z);
+
+            if (blkid == -1)
+                return -1;
+
+            if((blkid == WALLSIGN_ID) || (blkid == SIGNPOST_ID)) {
+                return 1;
+            } else {
+                return 0;
+            }
+        }
+
         @Override
         public void scheduleServerTask(Runnable run, long delay)
         {

forge-1.12.2/src/main/java/org/dynmap/forge_1_12_2/DynmapPlugin.java

@@ -146,6 +146,9 @@ public class DynmapPlugin
     private boolean useSaveFolder = true;
     private Field displayName = null; // MCPC+ display name
 
+    private static final int SIGNPOST_ID = 63;
+    private static final int WALLSIGN_ID = 68;
+
     private static final String[] TRIGGER_DEFAULTS = { "blockupdate", "chunkpopulate", "chunkgenerate" };
 
     private static final Pattern patternControlCode = Pattern.compile("(?i)\\u00A7[0-9A-FK-OR]");
@@ -523,6 +526,20 @@ public class DynmapPlugin
             return -1;
         }
 
+        @Override
+        public int isSignAt(String wname, int x, int y, int z) {
+            int blkid = this.getBlockIDAt(wname, x, y, z);
+
+            if (blkid == -1)
+                return -1;
+
+            if((blkid == WALLSIGN_ID) || (blkid == SIGNPOST_ID)) {
+                return 1;
+            } else {
+                return 0;
+            }
+        }
+
         @Override
         public void scheduleServerTask(Runnable run, long delay)
         {

forge-1.13.2/src/main/java/org/dynmap/forge_1_13_2/DynmapPlugin.java

@@ -157,6 +157,9 @@ public class DynmapPlugin
     private boolean useSaveFolder = true;
     private Field displayName = null; // MCPC+ display name
 
+    private static final int SIGNPOST_ID = 63;
+    private static final int WALLSIGN_ID = 68;
+
     private static final String[] TRIGGER_DEFAULTS = { "blockupdate", "chunkpopulate", "chunkgenerate" };
 
     private static final Pattern patternControlCode = Pattern.compile("(?i)\\u00A7[0-9A-FK-OR]");
@@ -514,6 +517,11 @@ public class DynmapPlugin
             return -1;
         }
 
+        @Override
+        public int isSignAt(String wname, int x, int y, int z) {
+            return -1;
+        }
+
         @Override
         public void scheduleServerTask(Runnable run, long delay)
         {

forge-1.8.9/src/main/java/org/dynmap/forge_1_8_9/DynmapPlugin.java

@@ -141,6 +141,9 @@ public class DynmapPlugin
     private boolean useSaveFolder = true;
     private Field displayName = null; // MCPC+ display name
 
+    private static final int SIGNPOST_ID = 63;
+    private static final int WALLSIGN_ID = 68;
+
     private static final String[] TRIGGER_DEFAULTS = { "blockupdate", "chunkpopulate", "chunkgenerate" };
 
     private static final Pattern patternControlCode = Pattern.compile("(?i)\\u00A7[0-9A-FK-OR]");
@@ -494,6 +497,20 @@ public class DynmapPlugin
             return -1;
         }
 
+        @Override
+        public int isSignAt(String wname, int x, int y, int z) {
+            int blkid = this.getBlockIDAt(wname, x, y, z);
+
+            if (blkid == -1)
+                return -1;
+
+            if((blkid == WALLSIGN_ID) || (blkid == SIGNPOST_ID)) {
+                return 1;
+            } else {
+                return 0;
+            }
+        }
+
         @Override
         public void scheduleServerTask(Runnable run, long delay)
         {

forge-1.9.4/src/main/java/org/dynmap/forge_1_9_4/DynmapPlugin.java

@@ -139,6 +139,9 @@ public class DynmapPlugin
     private boolean useSaveFolder = true;
     private Field displayName = null; // MCPC+ display name
 
+    private static final int SIGNPOST_ID = 63;
+    private static final int WALLSIGN_ID = 68;
+
     private static final String[] TRIGGER_DEFAULTS = { "blockupdate", "chunkpopulate", "chunkgenerate" };
 
     private static final Pattern patternControlCode = Pattern.compile("(?i)\\u00A7[0-9A-FK-OR]");
@@ -497,6 +500,20 @@ public class DynmapPlugin
             return -1;
         }
 
+        @Override
+        public int isSignAt(String wname, int x, int y, int z) {
+            int blkid = this.getBlockIDAt(wname, x, y, z);
+
+            if (blkid == -1)
+                return -1;
+
+            if((blkid == WALLSIGN_ID) || (blkid == SIGNPOST_ID)) {
+                return 1;
+            } else {
+                return 0;
+            }
+        }
+
         @Override
         public void scheduleServerTask(Runnable run, long delay)
         {

spigot/src/main/java/org/dynmap/bukkit/DynmapPlugin.java

@@ -28,6 +28,7 @@ import org.bukkit.World;
 import org.bukkit.block.Block;
 import org.bukkit.block.BlockFace;
 import org.bukkit.block.BlockState;
+import org.bukkit.block.Sign;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandSender;
 import org.bukkit.entity.Player;
@@ -213,6 +214,22 @@ public class DynmapPlugin extends JavaPlugin implements DynmapAPI {
             return -1;
         }
 
+        @Override
+        public int isSignAt(String wname, int x, int y, int z) {
+            World w = getServer().getWorld(wname);
+            if((w != null) && w.isChunkLoaded(x >> 4, z >> 4)) {
+                Block b = w.getBlockAt(x, y, z);
+                BlockState s = b.getState();
+
+                if (s instanceof Sign) {
+                    return 1;
+                } else {
+                    return 0;
+                }
+            }
+            return -1;
+        }
+
         @Override
         public void scheduleServerTask(Runnable run, long delay) {
             getServer().getScheduler().scheduleSyncDelayedTask(DynmapPlugin.this, run, delay);