diff --git a/code/map_data_render.js b/code/map_data_render.js
new file mode 100644
index 00000000..4c448e8e
--- /dev/null
+++ b/code/map_data_render.js
@@ -0,0 +1,60 @@
+// MAP DATA RENDER ////////////////////////////////////////////////
+// class to handle rendering into leaflet the JSON data from the servers
+
+
+
+window.Render = function() {
+
+}
+
+
+// start a render pass. called as we start to make the batch of data requests to the servers
+window.Render.prototype.startRenderPass = function() {
+  this.isRendering = true;
+
+  this.deletedGuid = {};  // object - represents the set of all deleted game entity GUIDs seen in a render pass
+}
+
+// process deleted entity list and entity data
+window.Render.prototype.processTileData(deleted, entities) {
+  this.processDeletedGameEntityGuids(deleted);
+  this.processGameEntities(entities);
+}
+
+
+window.Render.prototype.processDeletedGamEntityGuids(deleted) {
+  for(var i in deleted) {
+    var guid = deleted[i];
+
+    if ( !(guid in this.deletedGuid) ) {
+      this.deletedGuid[guid] = true;  // flag this guid as having being processed
+
+      // the original code this is based on checked to see if the guid was for a field - and if so, removed it from the linkedFields of the relevant portals
+      // given that the server will also return updated portals - and the linkedFields data is not actively used in IITC, this seems pointless.
+
+      this.deleteEntity(guid);
+
+    }
+  }
+
+}
+
+window.Render.prototype.processGameEntities(entities) {
+  for (var i in entities) {
+    var ent = entities[i];
+
+    this.renderEntity(ent);
+  }
+
+  // TODO: reconstruct links 'optimised' out of the data from the portal link data
+
+
+}
+
+// end a render pass. does any cleaning up required, postponed processing of data, etc. called when the render
+// is considered complete
+window.Render.prototype.endRenderPass = function() {
+
+  this.isRendering = false;
+}
+