Include file for SDL pen event handling.
This file describes operations for pressure-sensitive pen (stylus and/or eraser) handling, e.g., for input and drawing tablets or suitably equipped mobile / tablet devices.
To get started with pens:
which
== SDL_PEN_MOUSEID.We primarily identify pens by SDL_PenID. The implementation makes a best effort to relate each SDL_PenID to the same physical device during a session. Formerly valid SDL_PenID values remain valid even if a device disappears.
For identifying pens across sessions, the API provides the type SDL_GUID .