The glVertex library emulates the legacy OpenGL API, which has been deprecated in OpenGL core profiles. It is also a convenience wrapper around GLSL shaders, VBOs and FBOs.
Use map data to plan hikes or explore new areas. Includes 3D maps of terrain rendered in real-time; trace trails across the terrain and get height verses distance profiles; tile together adjacent maps to create seamless map areas. Reads USGS SDTS files.