From 7409820a8f7d51bfdedd11f852beac2212d7565b Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Mon, 18 Jan 2016 11:50:07 +0000
Subject: [PATCH] Added
 Simplifier::requiresDownSampling()/requiresDownSamplingImplementation() to
 make it possible for the Simplfifer::ContinueSimplificationCallback to be
 able to decide whether up or downsampling is required, removing the previous
 hardwards reliance on getSampleRatio<1.0.

---
 include/osgUtil/Simplifier | 15 +++++++++++++++
 src/osgUtil/Simplifier.cpp |  7 +++++--
 2 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/include/osgUtil/Simplifier b/include/osgUtil/Simplifier
index ea7a14038..4b19ec81a 100644
--- a/include/osgUtil/Simplifier
+++ b/include/osgUtil/Simplifier
@@ -59,6 +59,11 @@ class OSGUTIL_EXPORT Simplifier : public osg::NodeVisitor
                 {
                     return simplifier.continueSimplificationImplementation(nextError, numOriginalPrimitives, numRemainingPrimitives);
                 }
+                
+                virtual bool requiresDownSampling(const Simplifier& simplifier) const
+                {
+                    return simplifier.requiresDownSamplingImplementation();
+                }
 
             protected:
                 virtual ~ContinueSimplificationCallback() {}
@@ -80,7 +85,17 @@ class OSGUTIL_EXPORT Simplifier : public osg::NodeVisitor
             if (getSampleRatio()<1.0) return ((float)numRemainingPrimitives > ((float)numOriginalPrimitives) * getSampleRatio()) && nextError<=getMaximumError();
             else return ((float)numRemainingPrimitives < ((float)numOriginalPrimitives) * getSampleRatio()) && nextError>getMaximumLength();
         }
+        
+        bool requiresDownSampling() const
+        {
+            if (_continueSimplificationCallback.valid()) return _continueSimplificationCallback->requiresDownSampling(*this);
+            else return requiresDownSamplingImplementation();
+        }
 
+        virtual bool requiresDownSamplingImplementation() const
+        {
+            return getSampleRatio()<1.0;
+        }
 
         virtual void apply(osg::Geode& geode)
         {
diff --git a/src/osgUtil/Simplifier.cpp b/src/osgUtil/Simplifier.cpp
index ec2a98b7f..8e883ef99 100644
--- a/src/osgUtil/Simplifier.cpp
+++ b/src/osgUtil/Simplifier.cpp
@@ -1744,14 +1744,17 @@ void Simplifier::simplify(osg::Geometry& geometry, const IndexList& protectedPoi
 {
     OSG_INFO<<"++++++++++++++simplifier************"<<std::endl;
 
+    bool downSample = requiresDownSampling();
+
     EdgeCollapse ec;
-    ec.setComputeErrorMetricUsingLength(getSampleRatio()>=1.0);
+    ec.setComputeErrorMetricUsingLength(!downSample);
     ec.setGeometry(&geometry, protectedPoints);
     ec.updateErrorMetricForAllEdges();
 
     unsigned int numOriginalPrimitives = ec._triangleSet.size();
 
-    if (getSampleRatio()<1.0)
+    
+    if (downSample)
     {
         while (!ec._edgeSet.empty() &&
                continueSimplification((*ec._edgeSet.begin())->getErrorMetric() , numOriginalPrimitives, ec._triangleSet.size()) &&