Added osg::Image::setPixelFormat(..) and setInternalTextureFormat(), and

renamed osg::Image::pixelFormat(), internalTextureFormat(),dataType() to
osg::Image::getPixelFormat() etc.  These changes are to bring it more
into line with the style of the rest of the OSG.

Updated the rest of the distribution to take account for these names changes.

src/osg/Image.cpp

@@ -163,6 +163,29 @@ const unsigned int Image::computeRowWidthInBytes(int width,GLenum format,GLenum
 }
 
 
+void Image::setInternalTextureFormat(GLint internalFormat)
+{
+    // won't do any sanity checking right now, leave it to 
+    // OpenGL to make the call.
+    _internalTextureFormat = internalFormat;
+}
+
+void Image::setPixelFormat(const GLenum format)
+{
+    if (_pixelFormat==format) return; // do nothing if the same.
+
+    if (computeNumComponents(_pixelFormat)==computeNumComponents(format))
+    {
+       // if the two formats have the same number of componets then
+       // we can do a straight swap.
+        _pixelFormat = format;
+    }
+    else
+    {
+        notify(WARN)<<"Image::setPixelFormat(..) - warning, attempt to reset the pixel format with a different number of components."<<std::endl;
+    }
+}
+
 void Image::createImage(int s,int t,int r,
                         GLenum format,GLenum type,
                         int packing)