diff --git a/include/SDL3/SDL_events.h b/include/SDL3/SDL_events.h index 399e0feb96..779cc2fae8 100644 --- a/include/SDL3/SDL_events.h +++ b/include/SDL3/SDL_events.h @@ -707,6 +707,20 @@ typedef struct SDL_CameraDeviceEvent /** * Touch finger event structure (event.tfinger.*) * + * Coordinates in this event are normalized. `x` and `y` are normalized to a + * range between 0.0f and 1.0f, relative to the window, so (0,0) is the top + * left and (1,1) is the bottom right. Delta coordinates `dx` and `dy` are + * normalized in the ranges of -1.0f (traversed all the way from the bottom or + * right to all the way up or left) to 1.0f (traversed all the way from the + * top or left to all the way down or right). + * + * Note that while the coordinates are _normalized_, they are not _clamped_, + * which means in some circumstances you can get a value outside of this + * range. For example, a renderer using logical presentation might give a + * negative value when the touch is in the letterboxing. Some platforms might + * report a touch outside of the window, which will also be outside of the + * range. + * * \since This struct is available since SDL 3.0.0. */ typedef struct SDL_TouchFingerEvent