I am writing my own application to use and present elevation data. So far, I've been easily using the three arc second SRTM data presented in ArcInfo ASCII format. But now I'm looking to use the higher resolution 1/3 arc second data. And I find them downloadable in three formats: arcgrid, gridfloat, and img. No ASCII format.
I looked into the arcgrid format, and it looks utterly opaque and complicated. So here's the question if anyone knows: which of these three would be easiest to code for, to read the elevation data into a C or C++ array in my program. And if anyone has any code snippets to share, I'd love to see them.