Provided by: libsdl3-doc_3.2.10+ds-1_all 

NAME
SDL_STANDARD_GRAVITY - A constant to represent standard gravity for accelerometer sensors.
HEADER FILE
Defined in SDL3/SDL_sensor.h
SYNOPSIS
#include "SDL3/SDL.h" #define SDL_STANDARD_GRAVITY 9.80665f
DESCRIPTION
The accelerometer returns the current acceleration in SI meters per second squared. This measurement includes the force of gravity, so a device at rest will have an value of SDL_STANDARD_GRAVITY away from the center of the earth, which is a positive Y value.
AVAILABILITY
This macro is available since SDL 3.2.0. Simple Directmedia Layer SDL 3.2.10 SDL_STANDARD_GRAVITY(3)