This texture format sets bit 15 manually to 1. This is slow, and it's
better if the developer converts graphics in a way that the bit is already
set to 1.
Using global variables is generally discouraged. Now that NE_ProcessArg()
and NE_ProcessDualArg() exist, it's better to show how to use them instead
of NE_Process() and NE_ProcessDual() while using global variables.
Also, switch from "int main(void)" to "int main(int argc, char *argv[])".
