NAME

       SDL_PenAxis - Pen axis indices.

SYNOPSIS

       #include <SDL3/SDL_pen.h>

       typedef enum SDL_PenAxis
       {
           SDL_PEN_AXIS_PRESSURE,  /**< Pen pressure.  Unidirectional: 0 to 1.0 */
           SDL_PEN_AXIS_XTILT,     /**< Pen horizontal tilt angle.  Bidirectional: -90.0 to 90.0 (left-to-right). */
           SDL_PEN_AXIS_YTILT,     /**< Pen vertical tilt angle.  Bidirectional: -90.0 to 90.0 (top-to-down). */
           SDL_PEN_AXIS_DISTANCE,  /**< Pen distance to drawing surface.  Unidirectional: 0.0 to 1.0 */
           SDL_PEN_AXIS_ROTATION,  /**< Pen barrel rotation.  Bidirectional: -180 to 179.9 (clockwise, 0 is facing up, -180.0 is facing down). */
           SDL_PEN_AXIS_SLIDER,    /**< Pen finger wheel or slider (e.g., Airbrush Pen).  Unidirectional: 0 to 1.0 */
           SDL_PEN_AXIS_TANGENTIAL_PRESSURE,    /**< Pressure from squeezing the pen ("barrel pressure"). */
           SDL_PEN_AXIS_COUNT       /**< Total known pen axis types in this version of SDL. This number may grow in future releases! */
       } SDL_PenAxis;

DESCRIPTION

       These  are  the  valid  values for the axis field in SDL_PenAxisEvent.  All axes are either normalised to
       0..1 or report a (positive or negative) angle in degrees, with  0.0  representing  the  centre.  Not  all
       pens/backends support all axes: unsupported axes are always zero.

       To  convert angles for tilt and rotation into vector representation, use SDL_sinf on the XTILT, YTILT, or
       ROTATION component, for example:

       SDL_sinf(xtilt * SDL_PI_F / 180.0).

AVAILABILITY

       This enum is available since SDL 3.2.0.

Simple Directmedia Layer                           SDL 3.2.20                                 SDL_PenAxis(3type)