Obating an XRay effect

i am working on a medical software project i am facing a problem
i render a number of give slices from a volume dataset and i need to apply a blending on them to have an X-ray image effect, but i didn’t succeeded.
i have done this at past using delphi and an opengl extenstion library known as DGL using this code:
glEnable(GL_BLEND);
glBlendFunc(GL_CONSTANT_ALPHA_EXT, GL_ONE);
glBlendColorEXT(1.0, 1.0, 1.0, 1.0/npicNum);

now i am using Visual Studio 2008 C++ and opengl ihave used the GLEW extension but i didn’t find the similar method and constants that do the same effect as with the delphi.
Kindly, if any one have any suggestion it will be appreciated.

for constants, be sure to get glext.h and for glBlendColorEXT one can use GLEW or Glee if you don’t want to get the pointer yourself.

For reference :
http://www.opengl.org/wiki/Getting_started#OpenGL_2.0.2B_and_extensions

glBlendFunc(GL_ONE, GL_ONE); // additive blending

could be useful.

For the GLEW does it support 64-bit as icompiled it using VC++ 9 x64 and i get a linkage error due to the presence of the glBlendColorEXT method

Correct, this is what you need for an x-ray effect, or glBlendFunc(GL_SRC_ALPHA, GL_ONE); depending on whether your intensity is stored in color or alpha (or both).