From Terry Welsh, "Okay, here are the mods I wrote for drawing a filled bounding box

behind osgText::Text.  I made it so the box would get drawn using
whichever BackdropImplementation was selected.  However, I did not
implement STENCIL_BUFFER.  In that case it defaults to drawing the
bounding box using POLYGON_OFFSET instead.

Also made it so the BOUNDINGBOX and FILLEDBOUNDINGBOX are drawn with a
settable color and margin size.

While I was at it I tightened up the values applied with DEPTH_RANGE
and POLYGON_OFFSET, not just for drawing the bounding box but also for
drawing backdrop text (these values must be coupled since the bounding
box has to be drawn deeper in Z than the backdrop text).  The values
in use before seemed like overkill and I was seeing some z-clipping
with my background scenery in the case of DEPTH_RANGE.  If there was a
good reason for the large values please let me know...."

include/osgText/TextBase

@@ -194,15 +194,24 @@ public:
 
     enum DrawModeMask
     {
-        TEXT        = 1, /// default
-        BOUNDINGBOX = 2,
-        ALIGNMENT   = 4
+        TEXT              = 1, /// default
+        BOUNDINGBOX       = 2,
+        FILLEDBOUNDINGBOX = 4,
+        ALIGNMENT         = 8
     };
 
     void setDrawMode(unsigned int mode);
     
     unsigned int getDrawMode() const { return _drawMode; }
 
+    void setBoundingBoxMargin(float margin);
+    
+    float getBoundingBoxMargin() const { return _textBBMargin; }
+
+    void setBoundingBoxColor(const osg::Vec4& color){ _textBBColor = color; }
+    
+    const osg::Vec4& getBoundingBoxColor() const { return _textBBColor; }
+
     
     void setKerningType(KerningType kerningType) { _kerningType = kerningType; }
 
@@ -255,6 +264,8 @@ protected:
     bool                                    _autoRotateToScreen;
     Layout                                  _layout;
     unsigned int                            _drawMode;
+    float                                   _textBBMargin;
+    osg::Vec4                               _textBBColor;
     KerningType                             _kerningType;
     unsigned int                            _lineCount;