[Avida-SVN] r3019 - branches/movement/source/cpu

[welsberr at myxo.css.msu.edu]

Author: welsberr
Date: 2008-12-11 12:30:24 -0500 (Thu, 11 Dec 2008)
New Revision: 3019

Modified:
   branches/movement/source/cpu/cHardwareCPU.cc
Log:
Additional comments for cHardwareCPU.cc

Modified: branches/movement/source/cpu/cHardwareCPU.cc
===================================================================
--- branches/movement/source/cpu/cHardwareCPU.cc	2008-12-10 15:27:07 UTC (rev 3018)
+++ branches/movement/source/cpu/cHardwareCPU.cc	2008-12-11 17:30:24 UTC (rev 3019)
@@ -209,6 +209,7 @@
     tInstLibEntry<tMethod>("sense", &cHardwareCPU::Inst_SenseLog2, nInstFlag::STALL),           // If you add more sense instructions
     tInstLibEntry<tMethod>("sense-unit", &cHardwareCPU::Inst_SenseUnit, nInstFlag::STALL),      // and want to keep stats, also add
     tInstLibEntry<tMethod>("sense-m100", &cHardwareCPU::Inst_SenseMult100, nInstFlag::STALL),   // the names to cStats::cStats() @JEB
+	// @WRE: Single local knowledge sense instruction
 	tInstLibEntry<tMethod>("sense-diff-facing", &cHardwareCPU::Inst_SenseDiffFacing, nInstFlag::STALL),
     tInstLibEntry<tMethod>("if-resources", &cHardwareCPU::Inst_IfResources, nInstFlag::STALL),
     tInstLibEntry<tMethod>("collect", &cHardwareCPU::Inst_Collect, nInstFlag::STALL),
@@ -3320,11 +3321,17 @@
   // Note that we are converting <double> resources to <int> register values
 }
 
+// sense-diff-facing instruction
+// @WRE: 3 Oct 2008 
+// This implements a sense instruction that gets resource information from two cells,
+// the one currently occupied and the one currently faced, and puts the difference of those
+// values into the BX register, clearing the CX register. 
 bool cHardwareCPU::Inst_SenseDiffFacing(cAvidaContext& ctx)
 {
   return DoSenseDiffFacing(ctx, 1, 1000);
 }
- 
+
+// @WRE: Helper method that implements the sense-diff-facing instruction. 3 Oct 2008
 bool cHardwareCPU::DoSenseDiffFacing(cAvidaContext& ctx, int conversion_method, double base)
 {
   // Returns the amount of a resource or resources
@@ -3362,6 +3369,7 @@
   if (0 > organism->GetCellID()) return false;
   facedcellID = pop.GetCell(organism->GetCellID()).GetCellFaced().GetID();
   if (0 > facedcellID) return false;
+
   const tArray<double> & facedres_count = pop.GetResourceCount().GetCellResources(facedcellID);
 
   // Arbitrarily set to BX since the conditional instructions use this directly.
@@ -3429,13 +3437,13 @@
       if (conversion_method == 0) // Log
       {
         // for log, add together and then take log
-	dresource_result += ( (double) facedres_count[i] - (double) res_count[i]);
+        dresource_result += ( (double) facedres_count[i] - (double) res_count[i]);
       }
       else if (conversion_method == 1) // Addition of multiplied resource amount
       {
         int add_amount = ( (int) ((facedres_count[i] - res_count[i]) * base));
         // Do some range checking to make sure we don't overflow
-	resource_result = (INT_MAX - resource_result <= add_amount) ? INT_MAX : resource_result + add_amount;
+        resource_result = (INT_MAX - resource_result <= add_amount) ? INT_MAX : resource_result + add_amount;
       }
     }
   }