diff --git a/src/build_models/simplugin.h b/src/build_models/simplugin.h
new file mode 100644
--- /dev/null
+++ b/src/build_models/simplugin.h
@@ -0,0 +1,80 @@
+/*
+ * $Id$
+ *
+ * This file is part of the Virtual Leaf.
+ *
+ * The Virtual Leaf is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * The Virtual Leaf is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with the Virtual Leaf. If not, see .
+ *
+ * Copyright 2010 Roeland Merks.
+ *
+ */
+
+#ifndef _SIMPLUGIN_H_
+#define _SIMPLUGIN_H_
+
+#include
+#include
+#include "cellbase.h"
+#include "wallbase.h"
+
+class Parameter;
+
+#include
+#include
+
+
+class SimPluginInterface {
+
+public:
+ virtual QString ModelID(void) = 0;
+
+ virtual ~SimPluginInterface() { }
+
+ // Executed after the cellular mechanics steps have equillibrized
+ virtual void CellHouseKeeping(CellBase &c) = 0;
+
+ // Differential equations describing transport of chemicals from cell to cell
+ virtual void CelltoCellTransport(Wall *, double *dchem_c1, double *dchem_c2) = 0;
+
+ // Differential equations describing chemical reactions taking place at or near the cell walls
+ // (e.g. PIN accumulation)
+ virtual void WallDynamics(Wall *w, double *dw1, double *dw) = 0;
+
+ // Differential equations describing chemical reactions inside the cells
+ virtual void CellDynamics(CellBase *c, double *dchem) = 0;
+
+ // to be executed after a cell division
+ virtual void OnDivide(ParentInfo &parent_info, CellBase &daughter1, CellBase &daughter2) = 0;
+
+ // to be executed for coloring a cell
+ virtual void SetCellColor(CellBase &c, QColor &color) = 0;
+
+ // Number of chemicals
+ virtual int NChem(void) = 0;
+
+ // For internal use; not to be redefined by end users
+ virtual void SetParameters(Parameter *pass_pars);// { par = pass_pars; }
+ virtual void SetCellsStaticDatamembers (CellsStaticDatamembers *cells_static_data_members_of_main);
+
+protected:
+ class Parameter *par;
+
+};
+
+Q_DECLARE_INTERFACE(SimPluginInterface,
+ "nl.cwi.VirtualLeaf.SimPluginInterface/1.1")
+Q_DECLARE_METATYPE(SimPluginInterface *)
+
+
+#endif
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