From 68bb67312e417fc6d93bf8856609587114a380c6 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Tue, 13 Feb 2018 12:12:34 +0000
Subject: [PATCH] Improved handling of updates to the Texture target that
 require the texture to be reapplied. Used State for applying Texture target
 to work better with lazy state updating.

---
 src/osg/BindImageTexture.cpp | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/osg/BindImageTexture.cpp b/src/osg/BindImageTexture.cpp
index 592ffa2fb..14d71151a 100644
--- a/src/osg/BindImageTexture.cpp
+++ b/src/osg/BindImageTexture.cpp
@@ -15,17 +15,19 @@ int BindImageTexture::compare(const osg::StateAttribute &sa) const
     return 0;
 }
 
-void BindImageTexture::apply(osg::State&state) const
+void BindImageTexture::apply(osg::State& state) const
 {
     if(_target.valid())
     {
-        osg::Texture::TextureObject *to = _target->getTextureObject( state.getContextID() );
-        if( !to )
+        unsigned int contextID = state.getContextID();
+        osg::Texture::TextureObject *to = _target->getTextureObject( contextID );
+        if( !to || _target->isDirty( contextID ))
         {
-            // _target never been applied yet
-            _target->apply(state);
-            to = _target->getTextureObject( state.getContextID() );
+            // _target never been applied yet or is dirty
+            state.applyTextureAttribute( state.getActiveTextureUnit(), _target.get());
+            to = _target->getTextureObject( contextID );
         }
+
         state.get<osg::GLExtensions>()->glBindImageTexture(_imageunit, to->id(), _level, _layered, _layer, _access, _format);
     }