Fix support for paintings, also add a read and write position method.

src/main/java/us/myles/ViaVersion/PacketUtil.java

@@ -363,4 +363,17 @@ public class PacketUtil {
             e.printStackTrace();
         }
     }
+
+    public static long[] readBlockPosition(ByteBuf buf) {
+        long val = buf.readLong();
+        long x = (val >> 38); // signed
+        long y = (val >> 26) & 0xfff; // unsigned
+        // this shifting madness is used to preserve sign
+        long z = (val << 38) >> 38; // signed
+        return new long[]{x, y, z};
+    }
+
+    public static void writeBlockPosition(ByteBuf buf, long x, long y, long z) {
+        buf.writeLong(((x & 0x3ffffff) << 38) | ((y & 0xfff) << 26) | (z & 0x3ffffff));
+    }
 }

src/main/java/us/myles/ViaVersion/transformers/OutgoingTransformer.java

@@ -267,6 +267,23 @@ public class OutgoingTransformer {
 
             return;
         }
+        if (packet == PacketType.PLAY_SPAWN_PAINTING) {
+            int id = PacketUtil.readVarInt(input);
+            PacketUtil.writeVarInt(id, output);
+
+            PacketUtil.writeUUID(getUUID(id), output);
+
+            String title = PacketUtil.readString(input);
+            PacketUtil.writeString(title, output);
+
+            long[] position = PacketUtil.readBlockPosition(input);
+            PacketUtil.writeBlockPosition(output, position[0], position[1], position[2]);
+
+            byte direction = input.readByte();
+            output.writeByte(direction);
+
+            return;
+        }
         if (packet == PacketType.PLAY_OPEN_WINDOW) {
             int windowId = input.readUnsignedByte();
             String type = readString(input);