SDL_touch.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "../SDL_internal.h"
/* General touch handling code for SDL */
#include "SDL_assert.h"
#include "SDL_events.h"
#include "SDL_events_c.h"
static int SDL_num_touch = 0;
static SDL_Touch **SDL_touchDevices = NULL;
/* Public functions */
int
SDL_TouchInit(void)
{
return (0);
}
int
SDL_GetNumTouchDevices(void)
{
return SDL_num_touch;
}
SDL_TouchID
SDL_GetTouchDevice(int index)
{
if (index < 0 || index >= SDL_num_touch) {
SDL_SetError("Unknown touch device");
return 0;
}
return SDL_touchDevices[index]->id;
}
static int
SDL_GetTouchIndex(SDL_TouchID id)
{
int index;
SDL_Touch *touch;
for (index = 0; index < SDL_num_touch; ++index) {
touch = SDL_touchDevices[index];
if (touch->id == id) {
return index;
}
}
return -1;
}
SDL_Touch *
SDL_GetTouch(SDL_TouchID id)
{
int index = SDL_GetTouchIndex(id);
if (index < 0 || index >= SDL_num_touch) {
SDL_SetError("Unknown touch device");
return NULL;
}
return SDL_touchDevices[index];
}
static int
SDL_GetFingerIndex(const SDL_Touch * touch, SDL_FingerID fingerid)
{
int index;
for (index = 0; index < touch->num_fingers; ++index) {
if (touch->fingers[index]->id == fingerid) {
return index;
}
}
return -1;
}
SDL_Finger *
SDL_GetFinger(const SDL_Touch * touch, SDL_FingerID id)
{
int index = SDL_GetFingerIndex(touch, id);
if (index < 0 || index >= touch->num_fingers) {
return NULL;
}
return touch->fingers[index];
}
int
SDL_GetNumTouchFingers(SDL_TouchID touchID)
{
SDL_Touch *touch = SDL_GetTouch(touchID);
if (touch) {
return touch->num_fingers;
}
return 0;
}
SDL_Finger *
SDL_GetTouchFinger(SDL_TouchID touchID, int index)
{
SDL_Touch *touch = SDL_GetTouch(touchID);
if (!touch) {
return NULL;
}
if (index < 0 || index >= touch->num_fingers) {
SDL_SetError("Unknown touch finger");
return NULL;
}
return touch->fingers[index];
}
int
SDL_AddTouch(SDL_TouchID touchID, const char *name)
{
SDL_Touch **touchDevices;
int index;
index = SDL_GetTouchIndex(touchID);
if (index >= 0) {
return index;
}
/* Add the touch to the list of touch */
touchDevices = (SDL_Touch **) SDL_realloc(SDL_touchDevices,
(SDL_num_touch + 1) * sizeof(*touchDevices));
if (!touchDevices) {
return SDL_OutOfMemory();
}
SDL_touchDevices = touchDevices;
index = SDL_num_touch;
SDL_touchDevices[index] = (SDL_Touch *) SDL_malloc(sizeof(*SDL_touchDevices[index]));
if (!SDL_touchDevices[index]) {
return SDL_OutOfMemory();
}
/* Added touch to list */
++SDL_num_touch;
/* we're setting the touch properties */
SDL_touchDevices[index]->id = touchID;
SDL_touchDevices[index]->num_fingers = 0;
SDL_touchDevices[index]->max_fingers = 0;
SDL_touchDevices[index]->fingers = NULL;
/* Record this touch device for gestures */
/* We could do this on the fly in the gesture code if we wanted */
SDL_GestureAddTouch(touchID);
return index;
}
static int
SDL_AddFinger(SDL_Touch *touch, SDL_FingerID fingerid, float x, float y, float pressure)
{
SDL_Finger *finger;
if (touch->num_fingers == touch->max_fingers) {
SDL_Finger **new_fingers;
new_fingers = (SDL_Finger **)SDL_realloc(touch->fingers, (touch->max_fingers+1)*sizeof(*touch->fingers));
if (!new_fingers) {
return SDL_OutOfMemory();
}
touch->fingers = new_fingers;
touch->fingers[touch->max_fingers] = (SDL_Finger *)SDL_malloc(sizeof(*finger));
if (!touch->fingers[touch->max_fingers]) {
return SDL_OutOfMemory();
}
touch->max_fingers++;
}
finger = touch->fingers[touch->num_fingers++];
finger->id = fingerid;
finger->x = x;
finger->y = y;
finger->pressure = pressure;
return 0;
}
static int
SDL_DelFinger(SDL_Touch* touch, SDL_FingerID fingerid)
{
SDL_Finger *temp;
int index = SDL_GetFingerIndex(touch, fingerid);
if (index < 0) {
return -1;
}
touch->num_fingers--;
temp = touch->fingers[index];
touch->fingers[index] = touch->fingers[touch->num_fingers];
touch->fingers[touch->num_fingers] = temp;
return 0;
}
int
SDL_SendTouch(SDL_TouchID id, SDL_FingerID fingerid,
SDL_bool down, float x, float y, float pressure)
{
int posted;
SDL_Finger *finger;
SDL_Touch* touch = SDL_GetTouch(id);
if (!touch) {
return -1;
}
finger = SDL_GetFinger(touch, fingerid);
if (down) {
if (finger) {
/* This finger is already down */
return 0;
}
if (SDL_AddFinger(touch, fingerid, x, y, pressure) < 0) {
return 0;
}
posted = 0;
if (SDL_GetEventState(SDL_FINGERDOWN) == SDL_ENABLE) {
SDL_Event event;
event.tfinger.type = SDL_FINGERDOWN;
event.tfinger.touchId = id;
event.tfinger.fingerId = fingerid;
event.tfinger.x = x;
event.tfinger.y = y;
event.tfinger.dx = 0;
event.tfinger.dy = 0;
event.tfinger.pressure = pressure;
posted = (SDL_PushEvent(&event) > 0);
}
} else {
if (!finger) {
/* This finger is already up */
return 0;
}
posted = 0;
if (SDL_GetEventState(SDL_FINGERUP) == SDL_ENABLE) {
SDL_Event event;
event.tfinger.type = SDL_FINGERUP;
event.tfinger.touchId = id;
event.tfinger.fingerId = fingerid;
/* I don't trust the coordinates passed on fingerUp */
event.tfinger.x = finger->x;
event.tfinger.y = finger->y;
event.tfinger.dx = 0;
event.tfinger.dy = 0;
event.tfinger.pressure = pressure;
posted = (SDL_PushEvent(&event) > 0);
}
SDL_DelFinger(touch, fingerid);
}
return posted;
}
int
SDL_SendTouchMotion(SDL_TouchID id, SDL_FingerID fingerid,
float x, float y, float pressure)
{
SDL_Touch *touch;
SDL_Finger *finger;
int posted;
float xrel, yrel, prel;
touch = SDL_GetTouch(id);
if (!touch) {
return -1;
}
finger = SDL_GetFinger(touch,fingerid);
if (!finger) {
return SDL_SendTouch(id, fingerid, SDL_TRUE, x, y, pressure);
}
xrel = x - finger->x;
yrel = y - finger->y;
prel = pressure - finger->pressure;
/* Drop events that don't change state */
if (!xrel && !yrel && !prel) {
#if 0
printf("Touch event didn't change state - dropped!\n");
#endif
return 0;
}
/* Update internal touch coordinates */
finger->x = x;
finger->y = y;
finger->pressure = pressure;
/* Post the event, if desired */
posted = 0;
if (SDL_GetEventState(SDL_FINGERMOTION) == SDL_ENABLE) {
SDL_Event event;
event.tfinger.type = SDL_FINGERMOTION;
event.tfinger.touchId = id;
event.tfinger.fingerId = fingerid;
event.tfinger.x = x;
event.tfinger.y = y;
event.tfinger.dx = xrel;
event.tfinger.dy = yrel;
event.tfinger.pressure = pressure;
posted = (SDL_PushEvent(&event) > 0);
}
return posted;
}
void
SDL_DelTouch(SDL_TouchID id)
{
int i;
int index = SDL_GetTouchIndex(id);
SDL_Touch *touch = SDL_GetTouch(id);
if (!touch) {
return;
}
for (i = 0; i < touch->max_fingers; ++i) {
SDL_free(touch->fingers[i]);
}
SDL_free(touch->fingers);
SDL_free(touch);
SDL_num_touch--;
SDL_touchDevices[index] = SDL_touchDevices[SDL_num_touch];
}
void
SDL_TouchQuit(void)
{
int i;
for (i = SDL_num_touch; i--; ) {
SDL_DelTouch(SDL_touchDevices[i]->id);
}
SDL_assert(SDL_num_touch == 0);
SDL_free(SDL_touchDevices);
SDL_touchDevices = NULL;
}
/* vi: set ts=4 sw=4 expandtab: */
SDL_num_touch
static int SDL_num_touch
Definition: SDL_touch.c:30
id
GLuint id
Definition: SDL_opengl_glext.h:528
SDL_Touch::max_fingers
int max_fingers
Definition: SDL_touch_c.h:31
SDL_GetTouchDevice
SDL_TouchID SDL_GetTouchDevice(int index)
Get the touch ID with the given index, or 0 if the index is invalid.
Definition: SDL_touch.c:48
x
GLint GLint GLint GLint GLint x
Definition: SDL_opengl.h:1567
SDL_FingerID
Sint64 SDL_FingerID
Definition: SDL_touch.h:42
SDL_events.h
SDL_DelFinger
static int SDL_DelFinger(SDL_Touch *touch, SDL_FingerID fingerid)
Definition: SDL_touch.c:199
SDL_Touch::fingers
SDL_Finger ** fingers
Definition: SDL_touch_c.h:32
SDL_SendTouch
int SDL_SendTouch(SDL_TouchID id, SDL_FingerID fingerid, SDL_bool down, float x, float y, float pressure)
Definition: SDL_touch.c:216
SDL_ENABLE
#define SDL_ENABLE
Definition: SDL_events.h:718
SDL_GetFinger
SDL_Finger * SDL_GetFinger(const SDL_Touch *touch, SDL_FingerID id)
Definition: SDL_touch.c:96
name
GLuint const GLchar * name
Definition: SDL_opengl_glext.h:660
SDL_realloc
#define SDL_realloc
Definition: SDL_dynapi_overrides.h:382
SDL_Touch::id
SDL_TouchID id
Definition: SDL_touch_c.h:29
SDL_GetTouchIndex
static int SDL_GetTouchIndex(SDL_TouchID id)
Definition: SDL_touch.c:58
SDL_SendTouchMotion
int SDL_SendTouchMotion(SDL_TouchID id, SDL_FingerID fingerid, float x, float y, float pressure)
Definition: SDL_touch.c:278
SDL_bool
SDL_bool
Definition: SDL_stdinc.h:126
SDL_GestureAddTouch
int SDL_GestureAddTouch(SDL_TouchID touchId)
Definition: SDL_gesture.c:442
SDL_FINGERDOWN
Definition: SDL_events.h:125
SDL_GetEventState
#define SDL_GetEventState(type)
Definition: SDL_events.h:731
y
GLint GLint GLint GLint GLint GLint y
Definition: SDL_opengl.h:1567
event
struct _cl_event * event
Definition: SDL_opengl_glext.h:2649
SDL_free
void SDL_free(void *mem)
SDL_GetNumTouchFingers
int SDL_GetNumTouchFingers(SDL_TouchID touchID)
Get the number of active fingers for a given touch device.
Definition: SDL_touch.c:106
SDL_PushEvent
#define SDL_PushEvent
Definition: SDL_dynapi_overrides.h:131
SDL_DelTouch
void SDL_DelTouch(SDL_TouchID id)
Definition: SDL_touch.c:331
SDL_TouchID
Sint64 SDL_TouchID
Definition: SDL_touch.h:41
SDL_AddFinger
static int SDL_AddFinger(SDL_Touch *touch, SDL_FingerID fingerid, float x, float y, float pressure)
Definition: SDL_touch.c:172
SDL_TRUE
Definition: SDL_stdinc.h:129
SDL_FINGERMOTION
Definition: SDL_events.h:127
SDL_AddTouch
int SDL_AddTouch(SDL_TouchID touchID, const char *name)
Definition: SDL_touch.c:130
SDL_Finger::y
float y
Definition: SDL_touch.h:48
index
GLuint index
Definition: SDL_opengl_glext.h:660
SDL_GetTouchFinger
SDL_Finger * SDL_GetTouchFinger(SDL_TouchID touchID, int index)
Get the finger object of the given touch, with the given index.
Definition: SDL_touch.c:116
i
return Display return Display Bool Bool int int int return Display XEvent Bool(*) XPointer return Display return Display Drawable _Xconst char unsigned int unsigned int return Display Pixmap Pixmap XColor XColor unsigned int unsigned int return Display _Xconst char char int char return Display Visual unsigned int int int char unsigned int unsigned int in i)
Definition: SDL_x11sym.h:42
SDL_assert
#define SDL_assert(condition)
Definition: SDL_assert.h:167
SDL_events_c.h
SDL_Finger
Definition: SDL_touch.h:44
NULL
#define NULL
Definition: begin_code.h:143
SDL_OutOfMemory
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
SDL_SetError
#define SDL_SetError
Definition: SDL_dynapi_overrides.h:36
SDL_FINGERUP
Definition: SDL_events.h:126
SDL_Touch
Definition: SDL_touch_c.h:27
SDL_Touch::num_fingers
int num_fingers
Definition: SDL_touch_c.h:30
SDL_Finger::id
SDL_FingerID id
Definition: SDL_touch.h:46
SDL_GetNumTouchDevices
int SDL_GetNumTouchDevices(void)
Get the number of registered touch devices.
Definition: SDL_touch.c:42
SDL_Event
General event structure.
Definition: SDL_events.h:521
SDL_malloc
#define SDL_malloc
Definition: SDL_dynapi_overrides.h:380
SDL_touchDevices
static SDL_Touch ** SDL_touchDevices
Definition: SDL_touch.c:31
SDL_GetFingerIndex
static int SDL_GetFingerIndex(const SDL_Touch *touch, SDL_FingerID fingerid)
Definition: SDL_touch.c:84
SDL_Finger::pressure
float pressure
Definition: SDL_touch.h:49
SDL_GetTouch
SDL_Touch * SDL_GetTouch(SDL_TouchID id)
Definition: SDL_touch.c:73
SDL_TouchQuit
void SDL_TouchQuit(void)
Definition: SDL_touch.c:352
SDL_TouchInit
int SDL_TouchInit(void)
Definition: SDL_touch.c:36
SDL_assert.h
SDL_Finger::x
float x
Definition: SDL_touch.h:47