I don't think it was this tutorial, but something similar I did around 2006 after completing a year of games programming study. Generating noise as height maps, mapping height ranges for texture blending and creating these terrains had me hooked on programming. Sadly, web development was just a lot more lucrative, so I dropped C++ for C#, and only done games dev as a hobby every now and then. I love these kind of tutorials though, same with Open GL NeHe, Game Programming Gem books, GPU Gems, etc. Good times!