GLEnable(GL_VERTEX_PROGRAM_NV);
    
    unsigned int shader_num;  

    GLGenPrograms(1, &shader_num);
    GLBindProgram(GL_VERTEX_PROGRAM_NV, shader_num);
    GLLoadProgram(GL_VERTEX_PROGRAM_NV, shader_num, shader_string.length(), &shader_code.front());

    GLDisable(GL_VERTEX_PROGRAM_NV);