Touch input

These functions are declared in the main Allegro header file:

 #include <allegro5/allegro.h>

ALLEGRO_TOUCH_INPUT

typedef struct ALLEGRO_TOUCH_INPUT ALLEGRO_TOUCH_INPUT;

Source Code

An abstract data type representing a physical touch screen or touch pad.

Since: 5.1.0

ALLEGRO_TOUCH_INPUT_MAX_TOUCH_COUNT

#define ALLEGRO_TOUCH_INPUT_MAX_TOUCH_COUNT        16

Source Code

The maximum amount of simultaneous touches that can be detected.

Since: 5.1.0

ALLEGRO_TOUCH_STATE

typedef struct ALLEGRO_TOUCH_STATE ALLEGRO_TOUCH_STATE;

Source Code

This is a structure that is used to hold a “snapshot” of a touch at a particular instant.

Public fields (read only):

id - identifier of the touch. If the touch is valid, this is positive.
x - touch x position
y - touch y position
dx - touch relative x position
dy - touch relative y position
primary - TRUE if this touch is the primary one (usually the first one).
display - The ALLEGRO_DISPLAY that was touched.

Since: 5.1.0

ALLEGRO_TOUCH_INPUT_STATE

typedef struct ALLEGRO_TOUCH_INPUT_STATE ALLEGRO_TOUCH_INPUT_STATE;

Source Code

This is a structure that holds a snapshot of all simultaneous touches at a particular instant.

Public fields (read only):

touches - an array of ALLEGRO_TOUCH_STATE

Since: 5.1.0

ALLEGRO_MOUSE_EMULATION_MODE

typedef enum ALLEGRO_MOUSE_EMULATION_MODE

Source Code

Type of mouse emulation to apply.

ALLEGRO_MOUSE_EMULATION_NONE: Disables mouse emulation.
ALLEGRO_MOUSE_EMULATION_TRANSPARENT: Enables transparent mouse emulation.
ALLEGRO_MOUSE_EMULATION_INCLUSIVE: Enable inclusive mouse emulation.
ALLEGRO_MOUSE_EMULATION_EXCLUSIVE: Enables exclusive mouse emulation.
ALLEGRO_MOUSE_EMULATION_5_0_x: Enables mouse emulation that is backwards compatible with Allegro 5.0.x.

Since: 5.1.0

Unstable API: Seems of limited value, as touch input tends to have different semantics compared to mouse input.

al_install_touch_input

bool al_install_touch_input(void)

Source Code

Install a touch input driver, returning true if successful. If a touch input driver was already installed, returns true immediately.

Since: 5.1.0

al_uninstall_touch_input

void al_uninstall_touch_input(void)

Source Code

Uninstalls the active touch input driver. If no touch input driver was active, this function does nothing.

This function is automatically called when Allegro is shut down.

Since: 5.1.0

al_is_touch_input_installed

bool al_is_touch_input_installed(void)

Source Code

Returns true if al_install_touch_input was called successfully.

Since: 5.1.0

Examples:

al_get_touch_input_state

void al_get_touch_input_state(ALLEGRO_TOUCH_INPUT_STATE *ret_state)

Source Code

Gets the current touch input state. The touch information is copied into the ALLEGRO_TOUCH_INPUT_STATE you provide to this function.

Since: 5.1.0

al_set_mouse_emulation_mode

void al_set_mouse_emulation_mode(int mode)

Source Code

Sets the kind of mouse emulation for the touch input subsystem to perform.

Since: 5.1.0

Unstable API: Seems of limited value, as touch input tends to have different semantics compared to mouse input.

Examples:

ex_native_filechooser.c

al_get_mouse_emulation_mode

int al_get_mouse_emulation_mode(void)

Source Code

Returns the kind of mouse emulation which the touch input subsystem is set to perform.

Since: 5.1.0

Unstable API: Seems of limited value, as touch input tends to have different semantics compared to mouse input.

al_get_touch_input_event_source

ALLEGRO_EVENT_SOURCE *al_get_touch_input_event_source(void)

Source Code

Returns the global touch input event source. This event source generates touch input events.

Since: 5.1.0

Examples:

al_get_touch_input_mouse_emulation_event_source

ALLEGRO_EVENT_SOURCE *al_get_touch_input_mouse_emulation_event_source(void)

Source Code

Returns the global touch input event source for emulated mouse events. This event source generates emulated mouse events that are based on touch events.

Since: 5.1.0

Unstable API: Seems of limited value, as touch input tends to have different semantics compared to mouse input.

Examples:

Allegro version 5.2.10 (20231119) - Last updated: 2024-11-21 07:18:33 UTC