From 44b8b0177c3ac752b41987af31f9c47d9836de8c Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Tue, 31 May 2005 05:37:13 +0000
Subject: [PATCH] Added ability to toggle on/off the pre compile of OpenGL
 objects in the DatabasePager via the setDoPreCompile(bool) method or via the
 env var OSG_DO_PRE_COMPILE=ON or OFF.

---
 include/osgDB/DatabasePager | 11 +++++++++++
 src/osgDB/DatabasePager.cpp | 17 ++++++++++++-----
 2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/include/osgDB/DatabasePager b/include/osgDB/DatabasePager
index c387ebda8..3b8fc45a8 100644
--- a/include/osgDB/DatabasePager
+++ b/include/osgDB/DatabasePager
@@ -157,6 +157,16 @@ class OSGDB_EXPORT DatabasePager : public osg::NodeVisitor::DatabaseRequestHandl
           * note, should be only be called from the update thread. */
         virtual void registerPagedLODs(osg::Node* subgraph);
 
+        /** Set whether the database pager should pre compile OpenGL objects before allowing
+          * them to be merged into the scene graph.
+          * Pre compilation helps reduce the chances of frame drops, but also slows the
+          * speed at which tiles are merged as they have to be compiled first.*/
+        void setDoPreCompile(bool flag) { _doPreCompile = flag; }
+
+        /** Get whether the database pager should pre compile OpenGL objects before allowing
+          * them to be merged into the scene graph.*/
+        bool getDoPreCompile() const { return _doPreCompile; }
+
 
         /** Set the target frame rate that the DatabasePager should assume.
           * Typically one would set this to the value refresh rate of your display system i.e. 60Hz.
@@ -367,6 +377,7 @@ class OSGDB_EXPORT DatabasePager : public osg::NodeVisitor::DatabaseRequestHandl
 
         ActiveGraphicsContexts          _activeGraphicsContexts;
         
+        bool                            _doPreCompile;
         double                          _targetFrameRate;
         double                          _minimumTimeAvailableForGLCompileAndDeletePerFrame;
         unsigned int                    _maximumNumOfObjectsToCompilePerFrame;
diff --git a/src/osgDB/DatabasePager.cpp b/src/osgDB/DatabasePager.cpp
index 4c2b63081..ad3884c73 100644
--- a/src/osgDB/DatabasePager.cpp
+++ b/src/osgDB/DatabasePager.cpp
@@ -20,8 +20,9 @@
 using namespace osgDB;
 using namespace OpenThreads;
 
-static osg::ApplicationUsageProxy DatabasePager_e0(osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE,"OSG_MINIMUM_COMPILE_TIME_PER_FRAME <float>","minimum compile time alloted to compiling GL objects per frame in database pager.");
-static osg::ApplicationUsageProxy DatabasePager_e1(osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE,"OSG_MAXIMUM_OBJECTS_TO_COMPILE_PER_FRAME <int>","maximum number of GL objects to compile per frame in database pager.");
+static osg::ApplicationUsageProxy DatabasePager_e0(osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE,"OSG_DO_PRE_COMPILE <ON/OFF>","Switch on or off the pre compile of OpenGL object database pager.");
+static osg::ApplicationUsageProxy DatabasePager_e1(osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE,"OSG_MINIMUM_COMPILE_TIME_PER_FRAME <float>","minimum compile time alloted to compiling OpenGL objects per frame in database pager.");
+static osg::ApplicationUsageProxy DatabasePager_e2(osg::ApplicationUsage::ENVIRONMENTAL_VARIABLE,"OSG_MAXIMUM_OBJECTS_TO_COMPILE_PER_FRAME <int>","maximum number of OpenGL objects to compile per frame in database pager.");
 
 DatabasePager::DatabasePager()
 {
@@ -56,11 +57,17 @@ DatabasePager::DatabasePager()
     
     _expiryDelay = 10;
 
+    const char* ptr=0;
+    _doPreCompile = true;
+    if( (ptr = getenv("OSG_DO_PRE_COMPILE")) != 0)
+    {
+        _doPreCompile = strcmp(ptr,"yes")==0 || strcmp(ptr,"YES")==0 ||
+                        strcmp(ptr,"ON")==0 || strcmp(ptr,"ON")==0;
+    }
+
     _targetFrameRate = 100.0;
     _minimumTimeAvailableForGLCompileAndDeletePerFrame = 0.001; // 1ms.
     _maximumNumOfObjectsToCompilePerFrame = 8;
-
-    const char* ptr=0;
     if( (ptr = getenv("OSG_MINIMUM_COMPILE_TIME_PER_FRAME")) != 0)
     {
         _minimumTimeAvailableForGLCompileAndDeletePerFrame = atof(ptr);
@@ -462,7 +469,7 @@ void DatabasePager::run()
                 
                 bool loadedObjectsNeedToBeCompiled = false;
 
-                if (databaseRequest->_loadedModel.valid() && !_activeGraphicsContexts.empty())
+                if (_doPreCompile && databaseRequest->_loadedModel.valid() && !_activeGraphicsContexts.empty())
                 {
                     // force a compute of the loaded model's bounding volume, so that when the subgraph
                     // merged with the main scene graph and large computeBound() isn't incurred.