SDL pen event handling. More...

Collaboration diagram for Pen Support:

Typedefs
using	SDL::PenID = SDL_PenID
	SDL pen instance IDs. More...

using	SDL::PenInputFlags = Uint32
	Pen input flags, as reported by various pen events' `pen_state` field. More...

using	SDL::PenAxis = SDL_PenAxis
	Pen axis indices. More...

Variables
constexpr MouseID	SDL::PEN_MOUSEID = SDL_PEN_MOUSEID
	The MouseID for mouse events simulated with pen input. More...

constexpr TouchID	SDL::PEN_TOUCHID = SDL_PEN_TOUCHID
	The TouchID for touch events simulated with pen input. More...

constexpr PenInputFlags	SDL::PEN_INPUT_DOWN
	pen is pressed down More...

constexpr PenInputFlags	SDL::PEN_INPUT_BUTTON_1
	button 1 is pressed More...

constexpr PenInputFlags	SDL::PEN_INPUT_BUTTON_2
	button 2 is pressed More...

constexpr PenInputFlags	SDL::PEN_INPUT_BUTTON_3
	button 3 is pressed More...

constexpr PenInputFlags	SDL::PEN_INPUT_BUTTON_4
	button 4 is pressed More...

constexpr PenInputFlags	SDL::PEN_INPUT_BUTTON_5
	button 5 is pressed More...

constexpr PenInputFlags	SDL::PEN_INPUT_ERASER_TIP
	eraser tip is used More...

constexpr PenAxis	SDL::PEN_AXIS_PRESSURE
	Pen pressure. Unidirectional: 0 to 1.0. More...

constexpr PenAxis	SDL::PEN_AXIS_XTILT = SDL_PEN_AXIS_XTILT
	Pen horizontal tilt angle. Bidirectional: -90.0 to 90.0 (left-to-right).

constexpr PenAxis	SDL::PEN_AXIS_YTILT = SDL_PEN_AXIS_YTILT
	Pen vertical tilt angle. Bidirectional: -90.0 to 90.0 (top-to-down).

constexpr PenAxis	SDL::PEN_AXIS_DISTANCE = SDL_PEN_AXIS_DISTANCE
	Pen distance to drawing surface. Unidirectional: 0.0 to 1.0.

constexpr PenAxis	SDL::PEN_AXIS_ROTATION = SDL_PEN_AXIS_ROTATION
	Pen barrel rotation. More...

constexpr PenAxis	SDL::PEN_AXIS_SLIDER = SDL_PEN_AXIS_SLIDER
	Pen finger wheel or slider (e.g., Airbrush Pen). Unidirectional: 0 to 1.0.

constexpr PenAxis	SDL::PEN_AXIS_TANGENTIAL_PRESSURE
	Pressure from squeezing the pen ("barrel pressure"). More...

constexpr PenAxis	SDL::PEN_AXIS_COUNT = SDL_PEN_AXIS_COUNT
	Total known pen axis types in this version of SDL. More...

Detailed Description

SDL provides an API 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, simply handle SDL_EVENT_PEN_* events. When a pen starts providing input, SDL will assign it a unique PenID, which will remain for the life of the process, as long as the pen stays connected.

Pens may provide more than simple touch input; they might have other axes, such as pressure, tilt, rotation, etc.

Typedef Documentation

◆ PenAxis

using SDL::PenAxis = typedef SDL_PenAxis

These are the valid values for the axis field in 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 sin on the XTILT, YTILT, or ROTATION component, for example:

sin(xtilt * PI_F / 180.0).

Since: This enum is available since SDL 3.2.0.

◆ PenID

using SDL::PenID = typedef SDL_PenID

Zero is used to signify an invalid/null device.

These show up in pen events when SDL sees input from them. They remain consistent as long as SDL can recognize a tool to be the same pen; but if a pen physically leaves the area and returns, it might get a new ID.

Since: This datatype is available since SDL 3.2.0.

◆ PenInputFlags

using SDL::PenInputFlags = typedef Uint32

Since: This datatype is available since SDL 3.2.0.

Variable Documentation

◆ PEN_AXIS_COUNT

constexpr PenAxis SDL::PEN_AXIS_COUNT = SDL_PEN_AXIS_COUNT

constexpr

This number may grow in future releases!

◆ PEN_AXIS_PRESSURE

constexpr PenAxis SDL::PEN_AXIS_PRESSURE

constexpr

Initial value:

=

constexpr MouseID SDL::PEN_MOUSEID = SDL_PEN_MOUSEID

constexpr

Since: This macro is available since SDL 3.2.0.

◆ PEN_TOUCHID

constexpr TouchID SDL::PEN_TOUCHID = SDL_PEN_TOUCHID

constexpr

Since: This macro is available since SDL 3.2.0.

Typedefs

Variables

Detailed Description

Typedef Documentation

◆ PenAxis

◆ PenID

◆ PenInputFlags

Variable Documentation

◆ PEN_AXIS_COUNT

◆ PEN_AXIS_PRESSURE

◆ PEN_AXIS_ROTATION

◆ PEN_AXIS_TANGENTIAL_PRESSURE

◆ PEN_INPUT_BUTTON_1

◆ PEN_INPUT_BUTTON_2

◆ PEN_INPUT_BUTTON_3

◆ PEN_INPUT_BUTTON_4

◆ PEN_INPUT_BUTTON_5

◆ PEN_INPUT_DOWN

◆ PEN_INPUT_ERASER_TIP

◆ PEN_MOUSEID

◆ PEN_TOUCHID