diff --git a/src/proc/engine/dispatcher.hpp b/src/proc/engine/dispatcher.hpp
index 3f06bb94b..6f9d0af8d 100644
--- a/src/proc/engine/dispatcher.hpp
+++ b/src/proc/engine/dispatcher.hpp
@@ -26,6 +26,7 @@
 
 #include "proc/common.hpp"
 //#include "proc/state.hpp"
+#include "proc/mobject/model-port.hpp"
 #include "proc/engine/time-anchor.hpp"
 #include "proc/engine/frame-coord.hpp"
 #include "proc/engine/job-ticket.hpp"
@@ -38,6 +39,7 @@
 namespace proc {
 namespace engine {
   
+  using mobject::ModelPort;
   using lib::time::TimeSpan;
   using lib::time::FSecs;
   using lib::time::Time;
@@ -50,12 +52,21 @@ namespace engine {
   class Dispatcher
     : boost::noncopyable
     {
+      struct CoordBuilder
+        {
+          Dispatcher& dispatcher_;
+          ModelPort modelPort_;
+          uint channel_;
+          
+          FrameCoord relativeFrameLocation (TimeAnchor refPoint, uint frameCountOffset);    
+        };
       
     public:
       virtual ~Dispatcher();  ///< this is an interface
       
+      CoordBuilder onCalcStream (ModelPort modelPort, uint channel);
       
-      virtual FrameCoord locateFrameNext (uint frameCountOffset)   =0;
+      virtual FrameCoord locateFrameNext (uint frameCountOffset, TimeAnchor refPoint)   =0;
       
       JobTicket& accessJobTicket (FrameCoord const&);
       
diff --git a/src/proc/engine/time-anchor.hpp b/src/proc/engine/time-anchor.hpp
index f65f7fa30..40b7105e5 100644
--- a/src/proc/engine/time-anchor.hpp
+++ b/src/proc/engine/time-anchor.hpp
@@ -26,7 +26,6 @@
 
 #include "proc/common.hpp"
 //#include "proc/state.hpp"
-#include "proc/mobject/model-port.hpp"
 #include "lib/time/timevalue.hpp"
 #include "proc/play/timings.hpp"
 
@@ -35,10 +34,9 @@
 namespace proc {
 namespace engine {
   
-  using mobject::ModelPort;
 //  using lib::time::TimeSpan;
 //  using lib::time::FSecs;
-//  using lib::time::Time;
+  using lib::time::Time;
 //  
 //  class ExitNode;
   
@@ -59,6 +57,9 @@ namespace engine {
    */
   class TimeAnchor
     {
+      ///////////////////////////TODO need some kind of scale or grid here
+      uint64_t anchorPoint_;
+      Time relatedRealTime_;
       
       TimeAnchor()
         {
@@ -69,7 +70,7 @@ namespace engine {
       // using default copy operations
       
       static TimeAnchor
-      build (play::Timings timings, uint64_t startFrame, ModelPort modelPort, uint channel)
+      build (play::Timings timings, uint64_t startFrame)
         {
           UNIMPLEMENTED ("representation of the Time Anchor closure");
         }
diff --git a/tests/components/proc/engine/dispatcher-interface-test.cpp b/tests/components/proc/engine/dispatcher-interface-test.cpp
index be2c4bf91..005ebbb06 100644
--- a/tests/components/proc/engine/dispatcher-interface-test.cpp
+++ b/tests/components/proc/engine/dispatcher-interface-test.cpp
@@ -71,7 +71,7 @@ namespace test  {
         /* == mock Dispatcher implementation == */
         
         FrameCoord
-        locateFrameNext (uint frameCountOffset)
+        locateFrameNext (uint frameCountOffset, TimeAnchor refPoint)
           {
             UNIMPLEMENTED ("dummy implementation of the core dispatch operation");
           }
@@ -132,10 +132,11 @@ namespace test  {
           uint startFrame(10);
           uint channel(0);
           
-          TimeAnchor refPoint = TimeAnchor::build (timings, startFrame, modelPort, channel);
+          TimeAnchor refPoint = TimeAnchor::build (timings, startFrame);
           CHECK (refPoint == Time::ZERO + Duration(10, FrameRate::PAL));
           
-          FrameCoord coordinates = dispatcher.locateFrameNext (15);
+          FrameCoord coordinates = dispatcher.onCalcStream (modelPort,channel)
+                                             .relativeFrameLocation (refPoint, 15);
           CHECK (coordinates.absoluteNominalTime == Time(0,1));
           CHECK (coordinates.absoluteFrameNumber == 25);
           CHECK (coordinates.remainingRealTime() >= Time(FSecs(24,25)));