Ticket #4076: extend_templates.diff

binaries/data/mods/public/simulation/templates/template_structure_civic_civil_centre.EXTENDS.public.xml

@@ +1 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Entity>
+  <Health>
+    <Max op="mul">10</Max>
+  </Health>
+</Entity>

source/ps/TemplateLoader.cpp

@@ -1 @@
-/* Copyright (C) 2015 Wildfire Games.
+/* Copyright (C) 2016 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -175 +175 @@
     // Load the new file into the template data (overriding parent values)
     CParamNode::LoadXML(m_TemplateFileData[templateName], xero, wstring_from_utf8(templateName).c_str());
 
+    // Load extensions to the template (usually coming from other mods)
+    VfsPaths fileNames;
+
+    if (vfs::GetPathnames(g_VFS, VfsPath(TEMPLATE_ROOT), wstring_from_utf8(templateName + ".EXTENDS.*.xml").c_str(), fileNames) != INFO::OK)
+        return true; // No extensions found -> use regular data
+
+    for (const VfsPath& fileName : fileNames)
+    {
+        CXeromyces xero;
+        PSRETURN ok = xero.Load(g_VFS, fileName);
+        if (ok != PSRETURN_OK)
+            return false; // (Xeromyces already logged an error with the full filename)
+        CStr parentName = xero.GetRoot().GetAttributes().GetNamedItem(attr_parent);
+        if (!parentName.empty())
+        {
+            LOGERROR("Failed to load %s. Extended templates can't redefine template parents.", fileName.string().c_str());
+            return false;
+        }
+        CParamNode::LoadXML(m_TemplateFileData[templateName], xero, fileName.string().c_str());
+    }
+
     return true;
 }