SDL 3.0
SDL_touch.h
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1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>
4
5 This software is provided 'as-is', without any express or implied
6 warranty. In no event will the authors be held liable for any damages
7 arising from the use of this software.
8
9 Permission is granted to anyone to use this software for any purpose,
10 including commercial applications, and to alter it and redistribute it
11 freely, subject to the following restrictions:
12
13 1. The origin of this software must not be misrepresented; you must not
14 claim that you wrote the original software. If you use this software
15 in a product, an acknowledgment in the product documentation would be
16 appreciated but is not required.
17 2. Altered source versions must be plainly marked as such, and must not be
18 misrepresented as being the original software.
19 3. This notice may not be removed or altered from any source distribution.
20*/
21
22/**
23 * \file SDL_touch.h
24 *
25 * Include file for SDL touch event handling.
26 */
27
28#ifndef SDL_touch_h_
29#define SDL_touch_h_
30
31#include <SDL3/SDL_stdinc.h>
32#include <SDL3/SDL_error.h>
33#include <SDL3/SDL_video.h>
34
35#include <SDL3/SDL_begin_code.h>
36/* Set up for C function definitions, even when using C++ */
37#ifdef __cplusplus
38extern "C" {
39#endif
40
43
44typedef enum
45{
47 SDL_TOUCH_DEVICE_DIRECT, /* touch screen with window-relative coordinates */
48 SDL_TOUCH_DEVICE_INDIRECT_ABSOLUTE, /* trackpad with absolute device coordinates */
49 SDL_TOUCH_DEVICE_INDIRECT_RELATIVE /* trackpad with screen cursor-relative coordinates */
51
52typedef struct SDL_Finger
53{
55 float x;
56 float y;
57 float pressure;
59
60/* Used as the device ID for mouse events simulated with touch input */
61#define SDL_TOUCH_MOUSEID ((SDL_MouseID)-1)
62
63/* Used as the SDL_TouchID for touch events simulated with mouse input */
64#define SDL_MOUSE_TOUCHID ((SDL_TouchID)-1)
65
66
67/**
68 * Get a list of registered touch devices.
69 *
70 * On some platforms SDL first sees the touch device if it was actually used.
71 * Therefore the returned list might be empty, although devices are available.
72 * After using all devices at least once the number will be correct.
73 *
74 * This was fixed for Android in SDL 2.0.1.
75 *
76 * \param count a pointer filled in with the number of devices returned, can
77 * be NULL.
78 * \returns a 0 terminated array of touch device IDs which should be freed
79 * with SDL_free(), or NULL on error; call SDL_GetError() for more
80 * details.
81 *
82 * \since This function is available since SDL 3.0.0.
83 */
84extern DECLSPEC SDL_TouchID *SDLCALL SDL_GetTouchDevices(int *count);
85
86/**
87 * Get the touch device name as reported from the driver.
88 *
89 * You do not own the returned string, do not modify or free it.
90 *
91 * \param touchID the touch device instance ID.
92 * \returns touch device name, or NULL on error; call SDL_GetError() for more
93 * details.
94 *
95 * \since This function is available since SDL 3.0.0.
96 */
97extern DECLSPEC const char* SDLCALL SDL_GetTouchDeviceName(SDL_TouchID touchID);
98
99/**
100 * Get the type of the given touch device.
101 *
102 * \param touchID the ID of a touch device
103 * \returns touch device type
104 *
105 * \since This function is available since SDL 3.0.0.
106 */
108
109/**
110 * Get the number of active fingers for a given touch device.
111 *
112 * \param touchID the ID of a touch device
113 * \returns the number of active fingers for a given touch device on success
114 * or a negative error code on failure; call SDL_GetError() for more
115 * information.
116 *
117 * \since This function is available since SDL 3.0.0.
118 *
119 * \sa SDL_GetTouchFinger
120 */
121extern DECLSPEC int SDLCALL SDL_GetNumTouchFingers(SDL_TouchID touchID);
122
123/**
124 * Get the finger object for specified touch device ID and finger index.
125 *
126 * The returned resource is owned by SDL and should not be deallocated.
127 *
128 * \param touchID the ID of the requested touch device
129 * \param index the index of the requested finger
130 * \returns a pointer to the SDL_Finger object or NULL if no object at the
131 * given ID and index could be found.
132 *
133 * \since This function is available since SDL 3.0.0.
134 *
135 * \sa SDL_GetNumTouchFingers
136 */
137extern DECLSPEC SDL_Finger * SDLCALL SDL_GetTouchFinger(SDL_TouchID touchID, int index);
138
139/* Ends C function definitions when using C++ */
140#ifdef __cplusplus
141}
142#endif
143#include <SDL3/SDL_close_code.h>
144
145#endif /* SDL_touch_h_ */
uint64_t Uint64
Definition SDL_stdinc.h:187
Uint64 SDL_TouchID
Definition SDL_touch.h:41
SDL_TouchID * SDL_GetTouchDevices(int *count)
SDL_TouchDeviceType
Definition SDL_touch.h:45
@ SDL_TOUCH_DEVICE_INDIRECT_ABSOLUTE
Definition SDL_touch.h:48
@ SDL_TOUCH_DEVICE_DIRECT
Definition SDL_touch.h:47
@ SDL_TOUCH_DEVICE_INDIRECT_RELATIVE
Definition SDL_touch.h:49
@ SDL_TOUCH_DEVICE_INVALID
Definition SDL_touch.h:46
SDL_TouchDeviceType SDL_GetTouchDeviceType(SDL_TouchID touchID)
const char * SDL_GetTouchDeviceName(SDL_TouchID touchID)
int SDL_GetNumTouchFingers(SDL_TouchID touchID)
Uint64 SDL_FingerID
Definition SDL_touch.h:42
SDL_Finger * SDL_GetTouchFinger(SDL_TouchID touchID, int index)
float y
Definition SDL_touch.h:56
float pressure
Definition SDL_touch.h:57
SDL_FingerID id
Definition SDL_touch.h:54
float x
Definition SDL_touch.h:55