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SDL_syshaptic.c
795 lines (642 loc) · 19.6 KB
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/*
SDL - Simple DirectMedia Layer
Copyright (C) 2008 Edgar Simo
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Sam Lantinga
slouken@libsdl.org
*/
#include "SDL_config.h"
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#ifdef SDL_HAPTIC_LINUX
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#include "SDL_haptic.h"
#include "../SDL_syshaptic.h"
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#include "SDL_joystick.h"
#include "../../joystick/SDL_sysjoystick.h" /* For the real SDL_Joystick */
#include "../../joystick/linux/SDL_sysjoystick_c.h" /* For joystick hwdata */
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#include <unistd.h> /* close */
#include <linux/input.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <linux/limits.h>
#include <string.h>
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#include <errno.h>
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#include <math.h>
#ifndef M_PI
# define M_PI 3.14159265358979323846
#endif
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#define MAX_HAPTICS 32
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/*
* List of available haptic devices.
*/
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static struct
{
char *fname;
SDL_Haptic *haptic;
} SDL_hapticlist[MAX_HAPTICS];
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/*
* Haptic system hardware data.
*/
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struct haptic_hwdata
{
int fd;
};
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/*
* Haptic system effect data.
*/
struct haptic_hweffect
{
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struct ff_effect effect; /* The linux kernel effect structure. */
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};
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#define test_bit(nr, addr) \
(((1UL << ((nr) & 31)) & (((const unsigned int *) addr)[(nr) >> 5])) != 0)
#define EV_TEST(ev,f) \
if (test_bit((ev), features)) ret |= (f);
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/*
* Test whether a device has haptic properties.
* Returns available properties or 0 if there are none.
*/
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static int
EV_IsHaptic(int fd)
{
unsigned int ret;
unsigned long features[1 + FF_MAX/sizeof(unsigned long)];
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/* Ask device for what it has. */
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ret = 0;
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if (ioctl(fd, EVIOCGBIT(EV_FF, sizeof(features)), features) < 0) {
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SDL_SetError("Haptic: Unable to get device's features: %s", strerror(errno));
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return -1;
}
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/* Convert supported features to SDL_HAPTIC platform-neutral features. */
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EV_TEST(FF_CONSTANT, SDL_HAPTIC_CONSTANT);
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EV_TEST(FF_PERIODIC, SDL_HAPTIC_SINE |
SDL_HAPTIC_SQUARE |
SDL_HAPTIC_TRIANGLE |
SDL_HAPTIC_SAWTOOTHUP |
SDL_HAPTIC_SAWTOOTHDOWN);
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EV_TEST(FF_RAMP, SDL_HAPTIC_RAMP);
EV_TEST(FF_SPRING, SDL_HAPTIC_SPRING);
EV_TEST(FF_FRICTION, SDL_HAPTIC_FRICTION);
EV_TEST(FF_DAMPER, SDL_HAPTIC_DAMPER);
EV_TEST(FF_INERTIA, SDL_HAPTIC_INERTIA);
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EV_TEST(FF_CUSTOM, SDL_HAPTIC_CUSTOM);
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EV_TEST(FF_GAIN, SDL_HAPTIC_GAIN);
EV_TEST(FF_AUTOCENTER, SDL_HAPTIC_AUTOCENTER);
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/* Return what it supports. */
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return ret;
}
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/*
* Tests whether a device is a mouse or not.
*/
static int
EV_IsMouse(int fd)
{
unsigned long argp[40];
/* Ask for supported features. */
if (ioctl(fd, EVIOCGBIT(EV_KEY, sizeof(argp)), argp) < 0) {
return -1;
}
/* Currently we only test for BTN_MOUSE which can give fake positives. */
if (test_bit(BTN_MOUSE,argp) != 0) {
return 1;
}
return 0;
}
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/*
* Initializes the haptic subsystem by finding available devices.
*/
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int
SDL_SYS_HapticInit(void)
{
const char joydev_pattern[] = "/dev/input/event%d";
dev_t dev_nums[MAX_HAPTICS];
char path[PATH_MAX];
struct stat sb;
int fd;
int i, j, k;
int duplicate;
int numhaptics;
numhaptics = 0;
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/*
* Limit amount of checks to MAX_HAPTICS since we may or may not have
* permission to some or all devices.
*/
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i = 0;
for (j = 0; j < MAX_HAPTICS; ++j) {
snprintf(path, PATH_MAX, joydev_pattern, i++);
/* check to see if file exists */
if (stat(path,&sb) != 0)
break;
/* check for duplicates */
duplicate = 0;
for (k = 0; (k < numhaptics) && !duplicate; ++k) {
if (sb.st_rdev == dev_nums[k]) {
duplicate = 1;
}
}
if (duplicate) {
continue;
}
/* try to open */
fd = open(path, O_RDWR, 0);
if (fd < 0) continue;
#ifdef DEBUG_INPUT_EVENTS
printf("Checking %s\n", path);
#endif
/* see if it works */
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if (EV_IsHaptic(fd) > 0) {
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SDL_hapticlist[numhaptics].fname = SDL_strdup(path);
SDL_hapticlist[numhaptics].haptic = NULL;
dev_nums[numhaptics] = sb.st_rdev;
++numhaptics;
}
close(fd);
}
return numhaptics;
}
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/*
* Return the name of a haptic device, does not need to be opened.
*/
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const char *
SDL_SYS_HapticName(int index)
{
int fd;
static char namebuf[128];
char *name;
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/* Open the haptic device. */
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name = NULL;
fd = open(SDL_hapticlist[index].fname, O_RDONLY, 0);
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if (fd >= 0) {
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/* Check for name ioctl. */
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if (ioctl(fd, EVIOCGNAME(sizeof(namebuf)), namebuf) <= 0) {
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/* No name found, return device character device */
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name = SDL_hapticlist[index].fname;
}
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/* Name found, return name. */
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else {
name = namebuf;
}
}
close(fd);
return name;
}
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/*
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* Opens the haptic device from the file descriptor.
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*/
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static int
SDL_SYS_HapticOpenFromFD(SDL_Haptic * haptic, int fd)
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{
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/* Allocate the hwdata */
haptic->hwdata = (struct haptic_hwdata *)
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SDL_malloc(sizeof(*haptic->hwdata));
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if (haptic->hwdata == NULL) {
SDL_OutOfMemory();
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goto open_err;
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}
SDL_memset(haptic->hwdata, 0, sizeof(*haptic->hwdata));
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/* Set the data */
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haptic->hwdata->fd = fd;
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haptic->supported = EV_IsHaptic(fd);
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/* Set the effects */
if (ioctl(fd, EVIOCGEFFECTS, &haptic->neffects) < 0) {
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SDL_SetError("Haptic: Unable to query device memory: %s", strerror(errno));
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goto open_err;
}
haptic->effects = (struct haptic_effect *)
SDL_malloc(sizeof(struct haptic_effect) * haptic->neffects);
if (haptic->effects == NULL) {
SDL_OutOfMemory();
goto open_err;
}
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/* Clear the memory */
SDL_memset(haptic->effects, 0,
sizeof(struct haptic_effect) * haptic->neffects);
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return 0;
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/* Error handling */
open_err:
close(fd);
if (haptic->hwdata != NULL) {
free(haptic->hwdata);
haptic->hwdata = NULL;
}
return -1;
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}
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/*
* Opens a haptic device for usage.
*/
int
SDL_SYS_HapticOpen(SDL_Haptic * haptic)
{
int fd;
/* Open the character device */
fd = open(SDL_hapticlist[haptic->index].fname, O_RDWR, 0);
if (fd < 0) {
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SDL_SetError("Haptic: Unable to open %s: %s",
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SDL_hapticlist[haptic->index], strerror(errno));
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return -1;
}
return SDL_SYS_HapticOpenFromFD(haptic,fd);
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}
/*
* Opens a haptic device from first mouse it finds for usage.
*/
int
SDL_SYS_HapticMouse(void)
{
int fd;
int i;
for (i=0; i<SDL_numhaptics; i++) {
/* Open the device. */
fd = open(SDL_hapticlist[i].fname, O_RDWR, 0);
if (fd < 0) {
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SDL_SetError("Haptic: Unable to open %s: %s",
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SDL_hapticlist[i], strerror(errno));
return -1;
}
if (EV_IsMouse(fd)) {
close(fd);
return i;
}
close(fd);
}
return -1;
}
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/*
* Checks to see if a joystick has haptic features.
*/
int
SDL_SYS_JoystickIsHaptic(SDL_Joystick * joystick)
{
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return EV_IsHaptic(joystick->hwdata->fd);
}
/*
* Checks to see if the haptic device and joystick and in reality the same.
*/
int
SDL_SYS_JoystickSameHaptic(SDL_Haptic * haptic, SDL_Joystick * joystick)
{
if (SDL_strcmp(joystick->name,haptic->name)==0) {
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return 1;
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}
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return 0;
}
/*
* Opens a SDL_Haptic from a SDL_Joystick.
*/
int
SDL_SYS_HapticOpenFromJoystick(SDL_Haptic * haptic, SDL_Joystick * joystick)
{
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int fd;
fd = open(joystick->hwdata->fname, O_RDWR, 0);
return SDL_SYS_HapticOpenFromFD(haptic,fd);
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}
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/*
* Closes the haptic device.
*/
void
SDL_SYS_HapticClose(SDL_Haptic * haptic)
{
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if (haptic->hwdata) {
/* Clean up */
close(haptic->hwdata->fd);
/* Free */
SDL_free(haptic->hwdata);
haptic->hwdata = NULL;
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SDL_free(haptic->effects);
haptic->neffects = 0;
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}
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}
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/*
* Clean up after system specific haptic stuff
*/
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void
SDL_SYS_HapticQuit(void)
{
int i;
for (i=0; SDL_hapticlist[i].fname != NULL; i++) {
SDL_free(SDL_hapticlist[i].fname);
}
SDL_hapticlist[0].fname = NULL;
}
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/*
* Returns the ff_effect usable direction from a SDL_HapticDirection.
*/
static Uint16
SDL_SYS_ToDirection( SDL_HapticDirection * dir )
{
Uint32 tmp;
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float f; /* Ideally we'd use fixed point math instead of floats... */
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switch (dir->type) {
case SDL_HAPTIC_POLAR:
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/* Linux directions are inverted. */
tmp = (((18000 + dir->dir[0]) % 36000) * 0xFFFF) / 36000;
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return (Uint16) tmp;
case SDL_HAPTIC_CARTESIAN:
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/* We must invert "x" and "y" to go clockwise. */
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f = atan2(dir->dir[0], dir->dir[1]);
tmp = (int)(f*18000./M_PI) % 36000;
tmp = (tmp * 0xFFFF) / 36000;
return (Uint16) tmp;
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default:
return -1;
}
return 0;
}
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#define CLAMP(x) (((x) > 32767) ? 32767 : x)
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/*
* Initializes the linux effect struct from a haptic_effect.
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* Values above 32767 (for unsigned) are unspecified so we must clamp.
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*/
static int
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SDL_SYS_ToFFEffect( struct ff_effect * dest, SDL_HapticEffect * src )
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{
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int i;
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SDL_HapticConstant *constant;
SDL_HapticPeriodic *periodic;
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SDL_HapticCondition *condition;
SDL_HapticRamp *ramp;
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/* Clear up */
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SDL_memset(dest, 0, sizeof(struct ff_effect));
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switch (src->type) {
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case SDL_HAPTIC_CONSTANT:
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constant = &src->constant;
/* Header */
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dest->type = FF_CONSTANT;
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dest->direction = SDL_SYS_ToDirection(&constant->direction);
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/* Replay */
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dest->replay.length = CLAMP(constant->length);
dest->replay.delay = CLAMP(constant->delay);
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/* Trigger */
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dest->trigger.button = CLAMP(constant->button);
dest->trigger.interval = CLAMP(constant->interval);
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/* Constant */
dest->u.constant.level = constant->level;
/* Envelope */
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dest->u.constant.envelope.attack_length = CLAMP(constant->attack_length);
dest->u.constant.envelope.attack_level = CLAMP(constant->attack_level);
dest->u.constant.envelope.fade_length = CLAMP(constant->fade_length);
dest->u.constant.envelope.fade_level = CLAMP(constant->fade_level);
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break;
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case SDL_HAPTIC_SINE:
case SDL_HAPTIC_SQUARE:
case SDL_HAPTIC_TRIANGLE:
case SDL_HAPTIC_SAWTOOTHUP:
case SDL_HAPTIC_SAWTOOTHDOWN:
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periodic = &src->periodic;
/* Header */
dest->type = FF_PERIODIC;
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dest->direction = SDL_SYS_ToDirection(&periodic->direction);
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/* Replay */
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dest->replay.length = CLAMP(periodic->length);
dest->replay.delay = CLAMP(periodic->delay);
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/* Trigger */
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dest->trigger.button = CLAMP(periodic->button);
dest->trigger.interval = CLAMP(periodic->interval);
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/* Periodic */
if (periodic->type == SDL_HAPTIC_SINE)
dest->u.periodic.waveform = FF_SINE;
else if (periodic->type == SDL_HAPTIC_SQUARE)
dest->u.periodic.waveform = FF_SQUARE;
else if (periodic->type == SDL_HAPTIC_TRIANGLE)
dest->u.periodic.waveform = FF_TRIANGLE;
else if (periodic->type == SDL_HAPTIC_SAWTOOTHUP)
dest->u.periodic.waveform = FF_SAW_UP;
else if (periodic->type == SDL_HAPTIC_SAWTOOTHDOWN)
dest->u.periodic.waveform = FF_SAW_DOWN;
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dest->u.periodic.period = CLAMP(periodic->period);
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dest->u.periodic.magnitude = periodic->magnitude;
dest->u.periodic.offset = periodic->offset;
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dest->u.periodic.phase = CLAMP(periodic->phase);
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/* Envelope */
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dest->u.periodic.envelope.attack_length = CLAMP(periodic->attack_length);
dest->u.periodic.envelope.attack_level = CLAMP(periodic->attack_level);
dest->u.periodic.envelope.fade_length = CLAMP(periodic->fade_length);
dest->u.periodic.envelope.fade_level = CLAMP(periodic->fade_level);
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break;
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case SDL_HAPTIC_SPRING:
case SDL_HAPTIC_DAMPER:
case SDL_HAPTIC_INERTIA:
case SDL_HAPTIC_FRICTION:
condition = &src->condition;
/* Header */
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if (condition->type == SDL_HAPTIC_SPRING)
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dest->type = FF_SPRING;
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else if (condition->type == SDL_HAPTIC_DAMPER)
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dest->type = FF_DAMPER;
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else if (condition->type == SDL_HAPTIC_INERTIA)
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dest->type = FF_INERTIA;
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else if (condition->type == SDL_HAPTIC_FRICTION)
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dest->type = FF_FRICTION;
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dest->direction = 0; /* Handled by the condition-specifics. */
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/* Replay */
dest->replay.length = CLAMP(condition->length);
dest->replay.delay = CLAMP(condition->delay);
/* Trigger */
dest->trigger.button = CLAMP(condition->button);
dest->trigger.interval = CLAMP(condition->interval);
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/* Condition */
/* X axis */
dest->u.condition[0].right_saturation = CLAMP(condition->right_sat[0]);
dest->u.condition[0].left_saturation = CLAMP(condition->left_sat[0]);
dest->u.condition[0].right_coeff = condition->right_coeff[0];
dest->u.condition[0].left_coeff = condition->left_coeff[0];
dest->u.condition[0].deadband = CLAMP(condition->deadband[0]);
dest->u.condition[0].center = condition->center[0];
/* Y axis */
dest->u.condition[1].right_saturation = CLAMP(condition->right_sat[1]);
dest->u.condition[1].left_saturation = CLAMP(condition->left_sat[1]);
dest->u.condition[1].right_coeff = condition->right_coeff[1];
dest->u.condition[1].left_coeff = condition->left_coeff[1];
dest->u.condition[1].deadband = CLAMP(condition->deadband[1]);
dest->u.condition[1].center = condition->center[1];
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break;
case SDL_HAPTIC_RAMP:
ramp = &src->ramp;
/* Header */
dest->type = FF_RAMP;
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dest->direction = SDL_SYS_ToDirection(&ramp->direction);
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/* Replay */
dest->replay.length = CLAMP(ramp->length);
dest->replay.delay = CLAMP(ramp->delay);
/* Trigger */
dest->trigger.button = CLAMP(ramp->button);
dest->trigger.interval = CLAMP(ramp->interval);
/* Ramp */
dest->u.ramp.start_level = ramp->start;
dest->u.ramp.end_level = ramp->end;
/* Envelope */
dest->u.ramp.envelope.attack_length = CLAMP(ramp->attack_length);
dest->u.ramp.envelope.attack_level = CLAMP(ramp->attack_level);
dest->u.ramp.envelope.fade_length = CLAMP(ramp->fade_length);
dest->u.ramp.envelope.fade_level = CLAMP(ramp->fade_level);
break;
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default:
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SDL_SetError("Haptic: Unknown effect type.");
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return -1;
}
return 0;
}
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/*
* Creates a new haptic effect.
*/
int
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SDL_SYS_HapticNewEffect(SDL_Haptic * haptic, struct haptic_effect * effect,
SDL_HapticEffect * base)
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{
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struct ff_effect * linux_effect;
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/* Allocate the hardware effect */
effect->hweffect = (struct haptic_hweffect *)
SDL_malloc(sizeof(struct haptic_hweffect));
if (effect->hweffect == NULL) {
SDL_OutOfMemory();
return -1;
}
/* Prepare the ff_effect */
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linux_effect = &effect->hweffect->effect;
if (SDL_SYS_ToFFEffect( linux_effect, base ) != 0) {
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goto new_effect_err;
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}
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linux_effect->id = -1; /* Have the kernel give it an id */
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/* Upload the effect */
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if (ioctl(haptic->hwdata->fd, EVIOCSFF, linux_effect) < 0) {
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SDL_SetError("Haptic: Error uploading effect to the device: %s", strerror(errno));
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goto new_effect_err;
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}
return 0;
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new_effect_err:
free(effect->hweffect);
effect->hweffect = NULL;
return -1;
}
/*
* Updates an effect.
*
* Note: Dynamically updating the direction can in some cases force
* the effect to restart and run once.
*/
int SDL_SYS_HapticUpdateEffect(SDL_Haptic * haptic,
struct haptic_effect * effect, SDL_HapticEffect * data)
{
struct ff_effect linux_effect;
/* Create the new effect */
if (SDL_SYS_ToFFEffect( &linux_effect, data ) != 0) {
return -1;
}
linux_effect.id = effect->hweffect->effect.id;
/* See if it can be uploaded. */
if (ioctl(haptic->hwdata->fd, EVIOCSFF, &linux_effect) < 0) {
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SDL_SetError("Haptic: Error updating the effect: %s", strerror(errno));
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return -1;
}
/* Copy the new effect into memory. */
SDL_memcpy( &effect->hweffect->effect, &linux_effect, sizeof(struct ff_effect) );
return effect->hweffect->effect.id;
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}
/*
* Runs an effect.
*/
int
SDL_SYS_HapticRunEffect(SDL_Haptic * haptic, struct haptic_effect * effect)
{
struct input_event run;
/* Prepare to run the effect */
run.type = EV_FF;
run.code = effect->hweffect->effect.id;
run.value = 1;
if (write(haptic->hwdata->fd, (const void*) &run, sizeof(run)) < 0) {
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SDL_SetError("Haptic: Unable to run the effect: %s", strerror(errno));
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return -1;
}
return 0;
}
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/*
* Stops an effect.
*/
int
SDL_SYS_HapticStopEffect(SDL_Haptic * haptic, struct haptic_effect * effect)
{
struct input_event stop;
stop.type = EV_FF;
stop.code = effect->hweffect->effect.id;
stop.value = 0;
if (write(haptic->hwdata->fd, (const void*) &stop, sizeof(stop)) < 0) {
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SDL_SetError("Haptic: Unable to stop the effect: %s", strerror(errno));
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return -1;
}
return 0;
}
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/*
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* Frees the effect.
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*/
void
SDL_SYS_HapticDestroyEffect(SDL_Haptic * haptic, struct haptic_effect * effect)
{
if (ioctl(haptic->hwdata->fd, EVIOCRMFF, effect->hweffect->effect.id) < 0) {
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SDL_SetError("Haptic: Error removing the effect from the device: %s",
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strerror(errno));
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}
SDL_free(effect->hweffect);
effect->hweffect = NULL;
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}
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/*
* Gets the status of a haptic effect.
*/
int
SDL_SYS_HapticGetEffectStatus(SDL_Haptic * haptic, struct haptic_effect * effect)
{
#if 0 /* Not supported atm. */
struct input_event ie;
ie.type = EV_FF;
ie.type = EV_FF_STATUS;
ie.code = effect->hweffect->effect.id;
if (write(haptic->hwdata->fd, &ie, sizeof(ie)) < 0) {
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SDL_SetError("Haptic: Error getting device status.");
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return -1;
}
return 0;
#endif
return -1;
}
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/*
* Sets the gain.
*/
int
SDL_SYS_HapticSetGain(SDL_Haptic * haptic, int gain)
{
struct input_event ie;
ie.type = EV_FF;
ie.code = FF_GAIN;
ie.value = (0xFFFFUL * gain) / 100;
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if (write(haptic->hwdata->fd, &ie, sizeof(ie)) < 0) {
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SDL_SetError("Haptic: Error setting gain: %s", strerror(errno));
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return -1;
}
return 0;
}
/*
* Sets the autocentering.
*/
int
SDL_SYS_HapticSetAutocenter(SDL_Haptic * haptic, int autocenter)
{
struct input_event ie;
ie.type = EV_FF;
ie.code = FF_AUTOCENTER;
ie.value = (0xFFFFUL * autocenter) / 100;
if (write(haptic->hwdata->fd, &ie, sizeof(ie)) < 0) {
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SDL_SetError("Haptic: Error setting autocenter: %s", strerror(errno));
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return -1;
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}
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return 0;
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}
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#endif /* SDL_HAPTIC_LINUX */