From fbd2dfcf173cb1d2d809efdf2b83e3a202e021e3 Mon Sep 17 00:00:00 2001
From: Alex Wilson <yourpalal2@gmail.com>
Date: Mon, 23 Jan 2012 17:00:36 +1300
Subject: [PATCH] Refactor ActiveSetSolver::Find{Min|Max}s().

---
 src/libs/linprog/ActiveSetSolver.cpp | 88 +++++++++++++++-------------
 src/libs/linprog/ActiveSetSolver.h   |  8 ++-
 2 files changed, 54 insertions(+), 42 deletions(-)

diff --git a/src/libs/linprog/ActiveSetSolver.cpp b/src/libs/linprog/ActiveSetSolver.cpp
index 250d0b075d..aa592a23d5 100644
--- a/src/libs/linprog/ActiveSetSolver.cpp
+++ b/src/libs/linprog/ActiveSetSolver.cpp
@@ -293,6 +293,26 @@ EquationSystem::_EliminateColumn(int32 column, int32 startRow, int32 endRow)
 }
 
 
+namespace {
+
+
+Constraint*
+AddMinConstraint(LinearSpec* spec, Variable* var)
+{
+	return spec->AddConstraint(1, var, kEQ, 0, 5, 5);
+}
+
+
+Constraint*
+AddMaxConstraint(LinearSpec* spec, Variable* var)
+{
+	static const double kHugeValue = 32000;
+	return spec->AddConstraint(1, var, kEQ, kHugeValue, 5, 5);
+}
+
+};
+
+
 ActiveSetSolver::ActiveSetSolver(LinearSpec* linearSpec)
 	:
 	QPSolverInterface(linearSpec),
@@ -582,53 +602,14 @@ ActiveSetSolver::MaxSize(Variable* width, Variable* height)
 ResultType
 ActiveSetSolver::FindMaxs(const VariableList* variables)
 {
-	ConstraintList softConstraints;
-	_RemoveSoftConstraint(softConstraints);
-
-	const double kHugeValue = 32000;
-	ConstraintList maxConstraints;
-	for (int32 i = variables->CountItems() - 1; i >= 0; i--) {
-		maxConstraints.AddItem(fLinearSpec->AddConstraint(1,
-			variables->ItemAt(i), kEQ, kHugeValue, 5, 5));
-	}
-
-	ResultType result = Solve();
-
-	for (int32 i = maxConstraints.CountItems() - 1; i >= 0; i--)
-		fLinearSpec->RemoveConstraint(maxConstraints.ItemAt(i));
-
-	_AddSoftConstraint(softConstraints);
-
-	if (result != kOptimal)
-		TRACE("Could not solve the layout specification (%d). ", result);
-
-	return result;
+	return _FindWithConstraintsNoSoft(variables, AddMaxConstraint);
 }
 
 
 ResultType
 ActiveSetSolver::FindMins(const VariableList* variables)
 {
-	ConstraintList softConstraints;
-	_RemoveSoftConstraint(softConstraints);
-
-	ConstraintList minConstraints;
-	for (int32 i = variables->CountItems() - 1; i >= 0; i--) {
-		minConstraints.AddItem(fLinearSpec->AddConstraint(1,
-			variables->ItemAt(i), kEQ, 0, 5, 5));
-	}
-
-	ResultType result = Solve();
-
-	for (int32 i = minConstraints.CountItems() - 1; i >= 0; i--)
-		fLinearSpec->RemoveConstraint(minConstraints.ItemAt(i));
-
-	_AddSoftConstraint(softConstraints);
-
-	if (result != kOptimal)
-		TRACE("Could not solve the layout specification (%d). ", result);
-
-	return result;
+	return _FindWithConstraintsNoSoft(variables, AddMinConstraint);
 }
 
 
@@ -658,3 +639,28 @@ ActiveSetSolver::_AddSoftConstraint(const ConstraintList& list)
 	}
 }
 
+
+ResultType
+ActiveSetSolver::_FindWithConstraintsNoSoft(const VariableList* variables,
+	AddConstraintFunc constraintFunc)
+{
+	ConstraintList softConstraints;
+	_RemoveSoftConstraint(softConstraints);
+
+	ConstraintList constraints;
+	for (int32 i = variables->CountItems() - 1; i >= 0; i--) {
+		constraints.AddItem(constraintFunc(fLinearSpec, variables->ItemAt(i)));
+	}
+
+	ResultType result = Solve();
+
+	for (int32 i = constraints.CountItems() - 1; i >= 0; i--)
+		fLinearSpec->RemoveConstraint(constraints.ItemAt(i));
+
+	_AddSoftConstraint(softConstraints);
+
+	if (result != kOptimal)
+		TRACE("Could not solve the layout specification (%d). ", result);
+
+	return result;
+}
diff --git a/src/libs/linprog/ActiveSetSolver.h b/src/libs/linprog/ActiveSetSolver.h
index 4a5118666a..ec55b1c906 100644
--- a/src/libs/linprog/ActiveSetSolver.h
+++ b/src/libs/linprog/ActiveSetSolver.h
@@ -77,10 +77,16 @@ public:
 			ResultType			FindMaxs(const VariableList* variables);
 			ResultType			FindMins(const VariableList* variables);
 
-public:
+private:
 			void				_RemoveSoftConstraint(ConstraintList& list);
 			void				_AddSoftConstraint(const ConstraintList& list);
 
+	typedef Constraint* (*AddConstraintFunc)(LinearSpec* spec, Variable* var);
+
+			ResultType			_FindWithConstraintsNoSoft(
+									const VariableList* variables,
+									AddConstraintFunc constraintFunc);
+
 	const	VariableList&		fVariables;
 	const	ConstraintList&		fConstraints;