From Rob Radtke, "I recently ran into some issues trying to save/load a scene graph as a .ive file. The problems came about because the scene graph contained depth textures in it. I have attached a patch (against the current revision: 10919) that fixes the issues that I encountered. Both attachments contain the same patch--one is a .zip file that contains the modified files and the other is a text patch file. Here is a summary of the changes I made:

1) Add getShadowComparison() accessor function to osg::Texture class
2) Modify ReaderWriterTiff::writeTifStream() and _readColor() (in Image.cpp) to handle pixelFormat==GL_DEPTH_COMPONENT as if it were GL_LUMINANCE
3) Modify the Texture classes of the ive and osg plug-ins so that they save/load the following Texture members: _use_shadow_comparison, _shadow_compare_func and _shadow_texture_mode
"

src/osg/Image.cpp

@@ -1416,6 +1416,7 @@ Vec4 _readColor(GLenum pixelFormat, T* data,float scale)
 {
     switch(pixelFormat)
     {
+        case(GL_DEPTH_COMPONENT):   //intentionally fall through and execute the code for GL_LUMINANCE
         case(GL_LUMINANCE):         { float l = float(*data++)*scale; return Vec4(l, l, l, 1.0f); }
         case(GL_ALPHA):             { float a = float(*data++)*scale; return Vec4(1.0f, 1.0f, 1.0f, a); }
         case(GL_LUMINANCE_ALPHA):   { float l = float(*data++)*scale; float a = float(*data++)*scale; return Vec4(l,l,l,a); }