1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2022 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 "SDL_stdinc.h"
32#include "SDL_error.h"
33#include "SDL_video.h"
34
35#include "begin_code.h"
36/* Set up for C function definitions, even when using C++ */
37#ifdef __cplusplus
38extern "C" {
39#endif
40
41typedef Sint64 SDL_TouchID;
42typedef Sint64 SDL_FingerID;
43
44typedef enum
45{
46 SDL_TOUCH_DEVICE_INVALID = -1,
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 */
50} SDL_TouchDeviceType;
51
52typedef struct SDL_Finger
53{
54 SDL_FingerID id;
55 float x;
56 float y;
57 float pressure;
58} SDL_Finger;
59
60/* Used as the device ID for mouse events simulated with touch input */
61#define SDL_TOUCH_MOUSEID ((Uint32)-1)
62
63/* Used as the SDL_TouchID for touch events simulated with mouse input */
64#define SDL_MOUSE_TOUCHID ((Sint64)-1)
65
66
67/**
68 * Get the number of registered touch devices.
69 *
70 * On some platforms SDL first sees the touch device if it was actually used.
71 * Therefore SDL_GetNumTouchDevices() may return 0 although devices are
72 * available. After using all devices at least once the number will be
73 * correct.
74 *
75 * This was fixed for Android in SDL 2.0.1.
76 *
77 * \returns the number of registered touch devices.
78 *
79 * \since This function is available since SDL 2.0.0.
80 *
81 * \sa SDL_GetTouchDevice
82 */
83extern DECLSPEC int SDLCALL SDL_GetNumTouchDevices(void);
84
85/**
86 * Get the touch ID with the given index.
87 *
88 * \param index the touch device index
89 * \returns the touch ID with the given index on success or 0 if the index is
90 * invalid; call SDL_GetError() for more information.
91 *
92 * \since This function is available since SDL 2.0.0.
93 *
94 * \sa SDL_GetNumTouchDevices
95 */
96extern DECLSPEC SDL_TouchID SDLCALL SDL_GetTouchDevice(int index);
97
98/**
99 * Get the type of the given touch device.
100 *
101 * \since This function is available since SDL 2.0.10.
102 */
103extern DECLSPEC SDL_TouchDeviceType SDLCALL SDL_GetTouchDeviceType(SDL_TouchID touchID);
104
105/**
106 * Get the number of active fingers for a given touch device.
107 *
108 * \param touchID the ID of a touch device
109 * \returns the number of active fingers for a given touch device on success
110 * or 0 on failure; call SDL_GetError() for more information.
111 *
112 * \since This function is available since SDL 2.0.0.
113 *
114 * \sa SDL_GetTouchFinger
115 */
116extern DECLSPEC int SDLCALL SDL_GetNumTouchFingers(SDL_TouchID touchID);
117
118/**
119 * Get the finger object for specified touch device ID and finger index.
120 *
121 * The returned resource is owned by SDL and should not be deallocated.
122 *
123 * \param touchID the ID of the requested touch device
124 * \param index the index of the requested finger
125 * \returns a pointer to the SDL_Finger object or NULL if no object at the
126 * given ID and index could be found.
127 *
128 * \since This function is available since SDL 2.0.0.
129 *
130 * \sa SDL_RecordGesture
131 */
132extern DECLSPEC SDL_Finger * SDLCALL SDL_GetTouchFinger(SDL_TouchID touchID, int index);
133
134/* Ends C function definitions when using C++ */
135#ifdef __cplusplus
136}
137#endif
138#include "close_code.h"
139
140#endif /* SDL_touch_h_ */
141
142/* vi: set ts=4 sw=4 expandtab: */
143