SDL_haptic.h File Reference

The SDL haptic subsystem allows you to control haptic (force feedback) devices. More...

#include "SDL_stdinc.h"
#include "SDL_error.h"
#include "SDL_joystick.h"
#include "begin_code.h"
#include "close_code.h"

Include dependency graph for SDL_haptic.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

Data Structures
struct	SDL_HapticDirection
	Structure that represents a haptic direction. More...
struct	SDL_HapticConstant
	A structure containing a template for a Constant effect. More...
struct	SDL_HapticPeriodic
	A structure containing a template for a Periodic effect. More...
struct	SDL_HapticCondition
	A structure containing a template for a Condition effect. More...
struct	SDL_HapticRamp
	A structure containing a template for a Ramp effect. More...
struct	SDL_HapticLeftRight
	A structure containing a template for a Left/Right effect. More...
struct	SDL_HapticCustom
	A structure containing a template for the SDL_HAPTIC_CUSTOM effect. More...
union	SDL_HapticEffect
	The generic template for any haptic effect. More...

Macros
Haptic effects
#define	SDL_HAPTIC_CONSTANT   (1u<<0)
	Constant effect supported. More...
#define	SDL_HAPTIC_SINE   (1u<<1)
	Sine wave effect supported. More...
#define	SDL_HAPTIC_LEFTRIGHT   (1u<<2)
	Left/Right effect supported. More...
#define	SDL_HAPTIC_TRIANGLE   (1u<<3)
	Triangle wave effect supported. More...
#define	SDL_HAPTIC_SAWTOOTHUP   (1u<<4)
	Sawtoothup wave effect supported. More...
#define	SDL_HAPTIC_SAWTOOTHDOWN   (1u<<5)
	Sawtoothdown wave effect supported. More...
#define	SDL_HAPTIC_RAMP   (1u<<6)
	Ramp effect supported. More...
#define	SDL_HAPTIC_SPRING   (1u<<7)
	Spring effect supported - uses axes position. More...
#define	SDL_HAPTIC_DAMPER   (1u<<8)
	Damper effect supported - uses axes velocity. More...
#define	SDL_HAPTIC_INERTIA   (1u<<9)
	Inertia effect supported - uses axes acceleration. More...
#define	SDL_HAPTIC_FRICTION   (1u<<10)
	Friction effect supported - uses axes movement. More...
#define	SDL_HAPTIC_CUSTOM   (1u<<11)
	Custom effect is supported. More...
#define	SDL_HAPTIC_GAIN   (1u<<12)
	Device can set global gain. More...
#define	SDL_HAPTIC_AUTOCENTER   (1u<<13)
	Device can set autocenter. More...
#define	SDL_HAPTIC_STATUS   (1u<<14)
	Device can be queried for effect status. More...
#define	SDL_HAPTIC_PAUSE   (1u<<15)
	Device can be paused. More...

Direction encodings
#define	SDL_HAPTIC_POLAR   0
	Uses polar coordinates for the direction. More...
#define	SDL_HAPTIC_CARTESIAN   1
	Uses cartesian coordinates for the direction. More...
#define	SDL_HAPTIC_SPHERICAL   2
	Uses spherical coordinates for the direction. More...
#define	SDL_HAPTIC_STEERING_AXIS   3
	Use this value to play an effect on the steering wheel axis. This provides better compatibility across platforms and devices as SDL will guess the correct axis. More...
#define	SDL_HAPTIC_INFINITY   4294967295U
	Used to play a device an infinite number of times. More...
int	SDL_NumHaptics (void)
	Count the number of haptic devices attached to the system. More...
const char *	SDL_HapticName (int device_index)
	Get the implementation dependent name of a haptic device. More...
SDL_Haptic *	SDL_HapticOpen (int device_index)
	Opens a haptic device for use. More...
int	SDL_HapticOpened (int device_index)
	Checks if the haptic device at index has been opened. More...
int	SDL_HapticIndex (SDL_Haptic *haptic)
	Gets the index of a haptic device. More...
int	SDL_MouseIsHaptic (void)
	Gets whether or not the current mouse has haptic capabilities. More...
SDL_Haptic *	SDL_HapticOpenFromMouse (void)
	Tries to open a haptic device from the current mouse. More...
int	SDL_JoystickIsHaptic (SDL_Joystick *joystick)
	Checks to see if a joystick has haptic features. More...
SDL_Haptic *	SDL_HapticOpenFromJoystick (SDL_Joystick *joystick)
	Opens a haptic device for use from a joystick device. More...
void	SDL_HapticClose (SDL_Haptic *haptic)
	Closes a haptic device previously opened with SDL_HapticOpen(). More...
int	SDL_HapticNumEffects (SDL_Haptic *haptic)
	Returns the number of effects a haptic device can store. More...
int	SDL_HapticNumEffectsPlaying (SDL_Haptic *haptic)
	Returns the number of effects a haptic device can play at the same time. More...
unsigned int	SDL_HapticQuery (SDL_Haptic *haptic)
	Gets the haptic device's supported features in bitwise manner. More...
int	SDL_HapticNumAxes (SDL_Haptic *haptic)
	Gets the number of haptic axes the device has. More...
int	SDL_HapticEffectSupported (SDL_Haptic *haptic, SDL_HapticEffect *effect)
	Checks to see if effect is supported by haptic. More...
int	SDL_HapticNewEffect (SDL_Haptic *haptic, SDL_HapticEffect *effect)
	Creates a new haptic effect on the device. More...
int	SDL_HapticUpdateEffect (SDL_Haptic *haptic, int effect, SDL_HapticEffect *data)
	Updates the properties of an effect. More...
int	SDL_HapticRunEffect (SDL_Haptic *haptic, int effect, Uint32 iterations)
	Runs the haptic effect on its associated haptic device. More...
int	SDL_HapticStopEffect (SDL_Haptic *haptic, int effect)
	Stops the haptic effect on its associated haptic device. More...
void	SDL_HapticDestroyEffect (SDL_Haptic *haptic, int effect)
	Destroys a haptic effect on the device. More...
int	SDL_HapticGetEffectStatus (SDL_Haptic *haptic, int effect)
	Gets the status of the current effect on the haptic device. More...
int	SDL_HapticSetGain (SDL_Haptic *haptic, int gain)
	Sets the global gain of the device. More...
int	SDL_HapticSetAutocenter (SDL_Haptic *haptic, int autocenter)
	Sets the global autocenter of the device. More...
int	SDL_HapticPause (SDL_Haptic *haptic)
	Pauses a haptic device. More...
int	SDL_HapticUnpause (SDL_Haptic *haptic)
	Unpauses a haptic device. More...
int	SDL_HapticStopAll (SDL_Haptic *haptic)
	Stops all the currently playing effects on a haptic device. More...
int	SDL_HapticRumbleSupported (SDL_Haptic *haptic)
	Checks to see if rumble is supported on a haptic device. More...
int	SDL_HapticRumbleInit (SDL_Haptic *haptic)
	Initializes the haptic device for simple rumble playback. More...
int	SDL_HapticRumblePlay (SDL_Haptic *haptic, float strength, Uint32 length)
	Runs simple rumble on a haptic device. More...
int	SDL_HapticRumbleStop (SDL_Haptic *haptic)
	Stops the simple rumble on a haptic device. More...

Detailed Description

The SDL haptic subsystem allows you to control haptic (force feedback) devices.

The basic usage is as follows:

• Initialize the subsystem (SDL_INIT_HAPTIC).
• Open a haptic device.
  • SDL_HapticOpen() to open from index.
  • SDL_HapticOpenFromJoystick() to open from an existing joystick.
• Create an effect (SDL_HapticEffect).
• Upload the effect with SDL_HapticNewEffect().
• Run the effect with SDL_HapticRunEffect().
• (optional) Free the effect with SDL_HapticDestroyEffect().
• Close the haptic device with SDL_HapticClose().

Simple rumble example:

SDL_Haptic *haptic;
 
// Open the device
haptic = SDL_HapticOpen( 0 );
if (haptic == NULL)
   return -1;
 
// Initialize simple rumble
if (SDL_HapticRumbleInit( haptic ) != 0)
   return -1;
 
// Play effect at 50% strength for 2 seconds
if (SDL_HapticRumblePlay( haptic, 0.5, 2000 ) != 0)
   return -1;
SDL_Delay( 2000 );
 
// Clean up
SDL_HapticClose( haptic );

Complete example:

int test_haptic( SDL_Joystick * joystick ) {
   SDL_Haptic *haptic;
   SDL_HapticEffect effect;
   int effect_id;
 
   // Open the device
   haptic = SDL_HapticOpenFromJoystick( joystick );
   if (haptic == NULL) return -1; // Most likely joystick isn't haptic
 
   // See if it can do sine waves
   if ((SDL_HapticQuery(haptic) & SDL_HAPTIC_SINE)==0) {
      SDL_HapticClose(haptic); // No sine effect
      return -1;
   }
 
   // Create the effect
   memset( &effect, 0, sizeof(SDL_HapticEffect) ); // 0 is safe default
   effect.type = SDL_HAPTIC_SINE;
   effect.periodic.direction.type = SDL_HAPTIC_POLAR; // Polar coordinates
   effect.periodic.direction.dir[0] = 18000; // Force comes from south
   effect.periodic.period = 1000; // 1000 ms
   effect.periodic.magnitude = 20000; // 20000/32767 strength
   effect.periodic.length = 5000; // 5 seconds long
   effect.periodic.attack_length = 1000; // Takes 1 second to get max strength
   effect.periodic.fade_length = 1000; // Takes 1 second to fade away
 
   // Upload the effect
   effect_id = SDL_HapticNewEffect( haptic, &effect );
 
   // Test the effect
   SDL_HapticRunEffect( haptic, effect_id, 1 );
   SDL_Delay( 5000); // Wait for the effect to finish
 
   // We destroy the effect, although closing the device also does this
   SDL_HapticDestroyEffect( haptic, effect_id );
 
   // Close the device
   SDL_HapticClose(haptic);
 
   return 0; // Success
}

Definition in file SDL_haptic.h.

Macro Definition Documentation

SDL_HAPTIC_AUTOCENTER

#define SDL_HAPTIC_AUTOCENTER   (1u<<13)

Device can set autocenter.

Device supports setting autocenter.

See also

SDL_HapticSetAutocenter

Definition at line 291 of file SDL_haptic.h.

SDL_HAPTIC_CARTESIAN

#define SDL_HAPTIC_CARTESIAN   1

Uses cartesian coordinates for the direction.

See also

SDL_HapticDirection

Definition at line 330 of file SDL_haptic.h.

SDL_HAPTIC_CONSTANT

#define SDL_HAPTIC_CONSTANT   (1u<<0)

Constant effect supported.

Constant haptic effect.

See also

SDL_HapticCondition

Definition at line 163 of file SDL_haptic.h.

SDL_HAPTIC_CUSTOM

#define SDL_HAPTIC_CUSTOM   (1u<<11)

Custom effect is supported.

User defined custom haptic effect.

Definition at line 269 of file SDL_haptic.h.

SDL_HAPTIC_DAMPER

#define SDL_HAPTIC_DAMPER   (1u<<8)

Damper effect supported - uses axes velocity.

Condition haptic effect that simulates dampening. Effect is based on the axes velocity.

See also

SDL_HapticCondition

Definition at line 242 of file SDL_haptic.h.

SDL_HAPTIC_FRICTION

#define SDL_HAPTIC_FRICTION   (1u<<10)

Friction effect supported - uses axes movement.

Condition haptic effect that simulates friction. Effect is based on the axes movement.

See also

SDL_HapticCondition

Definition at line 262 of file SDL_haptic.h.

SDL_HAPTIC_GAIN

#define SDL_HAPTIC_GAIN   (1u<<12)

Device can set global gain.

Device supports setting the global gain.

See also

SDL_HapticSetGain

Definition at line 282 of file SDL_haptic.h.

SDL_HAPTIC_INERTIA

#define SDL_HAPTIC_INERTIA   (1u<<9)

Inertia effect supported - uses axes acceleration.

Condition haptic effect that simulates inertia. Effect is based on the axes acceleration.

See also

SDL_HapticCondition

Definition at line 252 of file SDL_haptic.h.

SDL_HAPTIC_INFINITY

#define SDL_HAPTIC_INFINITY   4294967295U

Used to play a device an infinite number of times.

See also

SDL_HapticRunEffect

Definition at line 360 of file SDL_haptic.h.

SDL_HAPTIC_LEFTRIGHT

#define SDL_HAPTIC_LEFTRIGHT   (1u<<2)

Left/Right effect supported.

Haptic effect for direct control over high/low frequency motors.

See also

SDL_HapticLeftRight

Warning

this value was SDL_HAPTIC_SQUARE right before 2.0.0 shipped. Sorry, we ran out of bits, and this is important for XInput devices.

Definition at line 183 of file SDL_haptic.h.

SDL_HAPTIC_PAUSE

#define SDL_HAPTIC_PAUSE   (1u<<15)

Device can be paused.

Devices supports being paused.

See also

SDL_HapticPause

SDL_HapticUnpause

Definition at line 310 of file SDL_haptic.h.

SDL_HAPTIC_POLAR

#define SDL_HAPTIC_POLAR   0

Uses polar coordinates for the direction.

See also

SDL_HapticDirection

Definition at line 323 of file SDL_haptic.h.

SDL_HAPTIC_RAMP

#define SDL_HAPTIC_RAMP   (1u<<6)

Ramp effect supported.

Ramp haptic effect.

See also

SDL_HapticRamp

Definition at line 222 of file SDL_haptic.h.

SDL_HAPTIC_SAWTOOTHDOWN

#define SDL_HAPTIC_SAWTOOTHDOWN   (1u<<5)

Sawtoothdown wave effect supported.

Periodic haptic effect that simulates saw tooth down waves.

See also

SDL_HapticPeriodic

Definition at line 213 of file SDL_haptic.h.

SDL_HAPTIC_SAWTOOTHUP

#define SDL_HAPTIC_SAWTOOTHUP   (1u<<4)

Sawtoothup wave effect supported.

Periodic haptic effect that simulates saw tooth up waves.

See also

SDL_HapticPeriodic

Definition at line 204 of file SDL_haptic.h.

SDL_HAPTIC_SINE

#define SDL_HAPTIC_SINE   (1u<<1)

Sine wave effect supported.

Periodic haptic effect that simulates sine waves.

See also

SDL_HapticPeriodic

Definition at line 172 of file SDL_haptic.h.

SDL_HAPTIC_SPHERICAL

#define SDL_HAPTIC_SPHERICAL   2

Uses spherical coordinates for the direction.

See also

SDL_HapticDirection

Definition at line 337 of file SDL_haptic.h.

SDL_HAPTIC_SPRING

#define SDL_HAPTIC_SPRING   (1u<<7)

Spring effect supported - uses axes position.

Condition haptic effect that simulates a spring. Effect is based on the axes position.

See also

SDL_HapticCondition

Definition at line 232 of file SDL_haptic.h.

SDL_HAPTIC_STATUS

#define SDL_HAPTIC_STATUS   (1u<<14)

Device can be queried for effect status.

Device supports querying effect status.

See also

SDL_HapticGetEffectStatus

Definition at line 300 of file SDL_haptic.h.

SDL_HAPTIC_STEERING_AXIS

#define SDL_HAPTIC_STEERING_AXIS   3

Use this value to play an effect on the steering wheel axis. This provides better compatibility across platforms and devices as SDL will guess the correct axis.

See also

SDL_HapticDirection

Definition at line 345 of file SDL_haptic.h.

SDL_HAPTIC_TRIANGLE

#define SDL_HAPTIC_TRIANGLE   (1u<<3)

Triangle wave effect supported.

Periodic haptic effect that simulates triangular waves.

See also

SDL_HapticPeriodic

Definition at line 195 of file SDL_haptic.h.

Function Documentation

SDL_HapticClose()

void SDL_HapticClose

(

SDL_Haptic *

haptic

)

Closes a haptic device previously opened with SDL_HapticOpen().

Parameters

haptic

Haptic device to close.

Definition at line 338 of file SDL_haptic.c.

{
    int i;
    SDL_Haptic *hapticlist;
    SDL_Haptic *hapticlistprev;
 
    /* Must be valid */
    if (!ValidHaptic(haptic)) {
        return;
    }
 
    /* Check if it's still in use */
    if (--haptic->ref_count > 0) {
        return;
    }
 
    /* Close it, properly removing effects if needed */
    for (i = 0; i < haptic->neffects; i++) {
        if (haptic->effects[i].hweffect != NULL) {
            SDL_HapticDestroyEffect(haptic, i);
        }
    }
    SDL_SYS_HapticClose(haptic);
 
    /* Remove from the list */
    hapticlist = SDL_haptics;
    hapticlistprev = NULL;
    while ( hapticlist )
    {
        if (haptic == hapticlist)
        {
            if ( hapticlistprev )
            {
                /* unlink this entry */
                hapticlistprev->next = hapticlist->next;
            }
            else
            {
                SDL_haptics = haptic->next;
            }
 
            break;
        }
        hapticlistprev = hapticlist;
        hapticlist = hapticlist->next;
    }
 
    /* Free */
    SDL_free(haptic);
}

References haptic, i, NULL, SDL_free, SDL_HapticDestroyEffect(), SDL_haptics, SDL_SYS_HapticClose(), and ValidHaptic().

Referenced by SDL_HapticQuit().

SDL_HapticDestroyEffect()

void SDL_HapticDestroyEffect	(	SDL_Haptic *	haptic,
		int	effect
	)

Destroys a haptic effect on the device.

This will stop the effect if it's running. Effects are automatically destroyed when the device is closed.

Parameters

haptic	Device to destroy the effect on.
effect	Identifier of the effect to destroy.

See also

SDL_HapticNewEffect

Definition at line 591 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic) || !ValidEffect(haptic, effect)) {
        return;
    }
 
    /* Not allocated */
    if (haptic->effects[effect].hweffect == NULL) {
        return;
    }
 
    SDL_SYS_HapticDestroyEffect(haptic, &haptic->effects[effect]);
}

References haptic, NULL, SDL_SYS_HapticDestroyEffect(), ValidEffect(), and ValidHaptic().

Referenced by SDL_HapticClose().

SDL_HapticEffectSupported()

int SDL_HapticEffectSupported	(	SDL_Haptic *	haptic,
		SDL_HapticEffect *	effect
	)

Checks to see if effect is supported by haptic.

Parameters

haptic	Haptic device to check on.
effect	Effect to check to see if it is supported.

Returns

SDL_TRUE if effect is supported, SDL_FALSE if it isn't or -1 on error.

See also

SDL_HapticQuery

SDL_HapticNewEffect

Definition at line 461 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    if ((haptic->supported & effect->type) != 0)
        return SDL_TRUE;
    return SDL_FALSE;
}

References haptic, SDL_FALSE, SDL_TRUE, SDL_HapticEffect::type, and ValidHaptic().

Referenced by SDL_HapticNewEffect().

SDL_HapticGetEffectStatus()

int SDL_HapticGetEffectStatus	(	SDL_Haptic *	haptic,
		int	effect
	)

Gets the status of the current effect on the haptic device.

Device must support the SDL_HAPTIC_STATUS feature.

Parameters

haptic	Haptic device to query the effect status on.
effect	Identifier of the effect to query its status.

Returns

0 if it isn't playing, 1 if it is playing or -1 on error.

See also

SDL_HapticRunEffect

SDL_HapticStopEffect

Definition at line 609 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic) || !ValidEffect(haptic, effect)) {
        return -1;
    }
 
    if ((haptic->supported & SDL_HAPTIC_STATUS) == 0) {
        return SDL_SetError("Haptic: Device does not support status queries.");
    }
 
    return SDL_SYS_HapticGetEffectStatus(haptic, &haptic->effects[effect]);
}

References haptic, SDL_HAPTIC_STATUS, SDL_SetError, SDL_SYS_HapticGetEffectStatus(), ValidEffect(), and ValidHaptic().

SDL_HapticIndex()

int SDL_HapticIndex

(

SDL_Haptic *

haptic

)

Gets the index of a haptic device.

Parameters

haptic

Haptic device to get the index of.

Returns

The index of the haptic device or -1 on error.

See also

SDL_HapticOpen

SDL_HapticOpened

Definition at line 203 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    return haptic->index;
}

References haptic, and ValidHaptic().

SDL_HapticName()

const char* SDL_HapticName

(

int

device_index

)

Get the implementation dependent name of a haptic device.

This can be called before any joysticks are opened. If no name can be found, this function returns NULL.

Parameters

device_index

Index of the device to get its name.

Returns

Name of the device or NULL on error.

See also

SDL_NumHaptics

Definition at line 96 of file SDL_haptic.c.

{
    if ((device_index < 0) || (device_index >= SDL_NumHaptics())) {
        SDL_SetError("Haptic: There are %d haptic devices available",
                     SDL_NumHaptics());
        return NULL;
    }
    return SDL_SYS_HapticName(device_index);
}

References NULL, SDL_NumHaptics(), SDL_SetError, and SDL_SYS_HapticName().

SDL_HapticNewEffect()

int SDL_HapticNewEffect	(	SDL_Haptic *	haptic,
		SDL_HapticEffect *	effect
	)

Creates a new haptic effect on the device.

Parameters

haptic	Haptic device to create the effect on.
effect	Properties of the effect to create.

Returns

The identifier of the effect on success or -1 on error.

See also

SDL_HapticUpdateEffect

SDL_HapticRunEffect

SDL_HapticDestroyEffect

Definition at line 476 of file SDL_haptic.c.

{
    int i;
 
    /* Check for device validity. */
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    /* Check to see if effect is supported */
    if (SDL_HapticEffectSupported(haptic, effect) == SDL_FALSE) {
        return SDL_SetError("Haptic: Effect not supported by haptic device.");
    }
 
    /* See if there's a free slot */
    for (i = 0; i < haptic->neffects; i++) {
        if (haptic->effects[i].hweffect == NULL) {
 
            /* Now let the backend create the real effect */
            if (SDL_SYS_HapticNewEffect(haptic, &haptic->effects[i], effect)
                != 0) {
                return -1;      /* Backend failed to create effect */
            }
 
            SDL_memcpy(&haptic->effects[i].effect, effect,
                       sizeof(SDL_HapticEffect));
            return i;
        }
    }
 
    return SDL_SetError("Haptic: Device has no free space left.");
}

References haptic, i, NULL, SDL_FALSE, SDL_HapticEffectSupported(), SDL_memcpy, SDL_SetError, SDL_SYS_HapticNewEffect(), and ValidHaptic().

Referenced by SDL_HapticRumbleInit().

SDL_HapticNumAxes()

int SDL_HapticNumAxes

(

SDL_Haptic *

haptic

)

Gets the number of haptic axes the device has.

See also

SDL_HapticDirection

Definition at line 448 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    return haptic->naxes;
}

References haptic, and ValidHaptic().

SDL_HapticNumEffects()

int SDL_HapticNumEffects

(

SDL_Haptic *

haptic

)

Returns the number of effects a haptic device can store.

On some platforms this isn't fully supported, and therefore is an approximation. Always check to see if your created effect was actually created and do not rely solely on SDL_HapticNumEffects().

Parameters

haptic

The haptic device to query effect max.

Returns

The number of effects the haptic device can store or -1 on error.

See also

SDL_HapticNumEffectsPlaying

SDL_HapticQuery

Definition at line 406 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    return haptic->neffects;
}

References haptic, and ValidHaptic().

SDL_HapticNumEffectsPlaying()

int SDL_HapticNumEffectsPlaying

(

SDL_Haptic *

haptic

)

Returns the number of effects a haptic device can play at the same time.

This is not supported on all platforms, but will always return a value. Added here for the sake of completeness.

Parameters

haptic

The haptic device to query maximum playing effects.

Returns

The number of effects the haptic device can play at the same time or -1 on error.

See also

SDL_HapticNumEffects

SDL_HapticQuery

Definition at line 420 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    return haptic->nplaying;
}

References haptic, and ValidHaptic().

SDL_HapticOpen()

SDL_Haptic* SDL_HapticOpen

(

int

device_index

)

Opens a haptic device for use.

The index passed as an argument refers to the N'th haptic device on this system.

When opening a haptic device, its gain will be set to maximum and autocenter will be disabled. To modify these values use SDL_HapticSetGain() and SDL_HapticSetAutocenter().

Parameters

device_index

Index of the device to open.

Returns

Device identifier or NULL on error.

See also

SDL_HapticIndex

SDL_HapticOpenFromMouse

SDL_HapticOpenFromJoystick

SDL_HapticClose

SDL_HapticSetGain

SDL_HapticSetAutocenter

SDL_HapticPause

SDL_HapticStopAll

Definition at line 111 of file SDL_haptic.c.

{
    SDL_Haptic *haptic;
    SDL_Haptic *hapticlist;
 
    if ((device_index < 0) || (device_index >= SDL_NumHaptics())) {
        SDL_SetError("Haptic: There are %d haptic devices available",
                     SDL_NumHaptics());
        return NULL;
    }
 
    hapticlist = SDL_haptics;
    /* If the haptic is already open, return it
    * TODO: Should we create haptic instance IDs like the Joystick API?
    */
    while ( hapticlist )
    {
        if (device_index == hapticlist->index) {
            haptic = hapticlist;
            ++haptic->ref_count;
            return haptic;
        }
        hapticlist = hapticlist->next;
    }
 
    /* Create the haptic device */
    haptic = (SDL_Haptic *) SDL_malloc((sizeof *haptic));
    if (haptic == NULL) {
        SDL_OutOfMemory();
        return NULL;
    }
 
    /* Initialize the haptic device */
    SDL_memset(haptic, 0, (sizeof *haptic));
    haptic->rumble_id = -1;
    haptic->index = device_index;
    if (SDL_SYS_HapticOpen(haptic) < 0) {
        SDL_free(haptic);
        return NULL;
    }
 
    /* Add haptic to list */
    ++haptic->ref_count;
    /* Link the haptic in the list */
    haptic->next = SDL_haptics;
    SDL_haptics = haptic;
 
    /* Disable autocenter and set gain to max. */
    if (haptic->supported & SDL_HAPTIC_GAIN)
        SDL_HapticSetGain(haptic, 100);
    if (haptic->supported & SDL_HAPTIC_AUTOCENTER)
        SDL_HapticSetAutocenter(haptic, 0);
 
    return haptic;
}

References haptic, NULL, SDL_free, SDL_HAPTIC_AUTOCENTER, SDL_HAPTIC_GAIN, SDL_haptics, SDL_HapticSetAutocenter(), SDL_HapticSetGain(), SDL_malloc, SDL_memset, SDL_NumHaptics(), SDL_OutOfMemory, SDL_SetError, and SDL_SYS_HapticOpen().

Referenced by SDL_HapticOpenFromMouse().

SDL_HapticOpened()

int SDL_HapticOpened

(

int

device_index

)

Checks if the haptic device at index has been opened.

Parameters

device_index

Index to check to see if it has been opened.

Returns

1 if it has been opened or 0 if it hasn't.

See also

SDL_HapticOpen

SDL_HapticIndex

Definition at line 172 of file SDL_haptic.c.

{
    int opened;
    SDL_Haptic *hapticlist;
 
    /* Make sure it's valid. */
    if ((device_index < 0) || (device_index >= SDL_NumHaptics())) {
        SDL_SetError("Haptic: There are %d haptic devices available",
                     SDL_NumHaptics());
        return 0;
    }
 
    opened = 0;
    hapticlist = SDL_haptics;
    /* TODO Should this use an instance ID? */
    while ( hapticlist )
    {
        if (hapticlist->index == (Uint8) device_index) {
            opened = 1;
            break;
        }
        hapticlist = hapticlist->next;
    }
    return opened;
}

References SDL_haptics, SDL_NumHaptics(), and SDL_SetError.

SDL_HapticOpenFromJoystick()

SDL_Haptic* SDL_HapticOpenFromJoystick

(

SDL_Joystick *

joystick

)

Opens a haptic device for use from a joystick device.

You must still close the haptic device separately. It will not be closed with the joystick.

When opening from a joystick you should first close the haptic device before closing the joystick device. If not, on some implementations the haptic device will also get unallocated and you'll be unable to use force feedback on that device.

Parameters

joystick

Joystick to create a haptic device from.

Returns

A valid haptic device identifier on success or NULL on error.

See also

SDL_HapticOpen

SDL_HapticClose

Definition at line 272 of file SDL_haptic.c.

{
    SDL_Haptic *haptic;
    SDL_Haptic *hapticlist;
 
    /* Make sure there is room. */
    if (SDL_NumHaptics() <= 0) {
        SDL_SetError("Haptic: There are %d haptic devices available",
                     SDL_NumHaptics());
        return NULL;
    }
 
    /* Must be a valid joystick */
    if (!SDL_PrivateJoystickValid(joystick)) {
        SDL_SetError("Haptic: Joystick isn't valid.");
        return NULL;
    }
 
    /* Joystick must be haptic */
    if (SDL_SYS_JoystickIsHaptic(joystick) <= 0) {
        SDL_SetError("Haptic: Joystick isn't a haptic device.");
        return NULL;
    }
 
    hapticlist = SDL_haptics;
    /* Check to see if joystick's haptic is already open */
    while ( hapticlist )
    {
        if (SDL_SYS_JoystickSameHaptic(hapticlist, joystick)) {
            haptic = hapticlist;
            ++haptic->ref_count;
            return haptic;
        }
        hapticlist = hapticlist->next;
    }
 
    /* Create the haptic device */
    haptic = (SDL_Haptic *) SDL_malloc((sizeof *haptic));
    if (haptic == NULL) {
        SDL_OutOfMemory();
        return NULL;
    }
 
    /* Initialize the haptic device */
    SDL_memset(haptic, 0, sizeof(SDL_Haptic));
    haptic->rumble_id = -1;
    if (SDL_SYS_HapticOpenFromJoystick(haptic, joystick) < 0) {
        SDL_SetError("Haptic: SDL_SYS_HapticOpenFromJoystick failed.");
        SDL_free(haptic);
        return NULL;
    }
 
    /* Add haptic to list */
    ++haptic->ref_count;
    /* Link the haptic in the list */
    haptic->next = SDL_haptics;
    SDL_haptics = haptic;
 
    return haptic;
}

References haptic, joystick, NULL, SDL_free, SDL_haptics, SDL_malloc, SDL_memset, SDL_NumHaptics(), SDL_OutOfMemory, SDL_PrivateJoystickValid(), SDL_SetError, SDL_SYS_HapticOpenFromJoystick(), SDL_SYS_JoystickIsHaptic(), and SDL_SYS_JoystickSameHaptic().

SDL_HapticOpenFromMouse()

SDL_Haptic* SDL_HapticOpenFromMouse

(

void

)

Tries to open a haptic device from the current mouse.

Returns

The haptic device identifier or NULL on error.

See also

SDL_MouseIsHaptic

SDL_HapticOpen

Definition at line 229 of file SDL_haptic.c.

{
    int device_index;
 
    device_index = SDL_SYS_HapticMouse();
 
    if (device_index < 0) {
        SDL_SetError("Haptic: Mouse isn't a haptic device.");
        return NULL;
    }
 
    return SDL_HapticOpen(device_index);
}

References NULL, SDL_HapticOpen(), SDL_SetError, and SDL_SYS_HapticMouse().

SDL_HapticPause()

int SDL_HapticPause

(

SDL_Haptic *

haptic

)

Pauses a haptic device.

Device must support the SDL_HAPTIC_PAUSE feature. Call SDL_HapticUnpause() to resume playback.

Do not modify the effects nor add new ones while the device is paused. That can cause all sorts of weird errors.

Parameters

haptic

Haptic device to pause.

Returns

0 on success or -1 on error.

See also

SDL_HapticUnpause

Definition at line 696 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    if ((haptic->supported & SDL_HAPTIC_PAUSE) == 0) {
        return SDL_SetError("Haptic: Device does not support setting pausing.");
    }
 
    return SDL_SYS_HapticPause(haptic);
}

References haptic, SDL_HAPTIC_PAUSE, SDL_SetError, SDL_SYS_HapticPause(), and ValidHaptic().

SDL_HapticQuery()

unsigned int SDL_HapticQuery

(

SDL_Haptic *

haptic

)

Gets the haptic device's supported features in bitwise manner.

Example:

if (SDL_HapticQuery(haptic) & SDL_HAPTIC_CONSTANT) {
    printf("We have constant haptic effect!\n");
}

Parameters

haptic

The haptic device to query.

Returns

Haptic features in bitwise manner (OR'd).

See also

SDL_HapticNumEffects

SDL_HapticEffectSupported

Definition at line 434 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return 0; /* same as if no effects were supported */
    }
 
    return haptic->supported;
}

References haptic, and ValidHaptic().

SDL_HapticRumbleInit()

int SDL_HapticRumbleInit

(

SDL_Haptic *

haptic

)

Initializes the haptic device for simple rumble playback.

Parameters

haptic

Haptic device to initialize for simple rumble playback.

Returns

0 on success or -1 on error.

See also

SDL_HapticOpen

SDL_HapticRumbleSupported

SDL_HapticRumblePlay

SDL_HapticRumbleStop

Definition at line 757 of file SDL_haptic.c.

{
    SDL_HapticEffect *efx = &haptic->rumble_effect;
 
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    /* Already allocated. */
    if (haptic->rumble_id >= 0) {
        return 0;
    }
 
    SDL_zerop(efx);
    if (haptic->supported & SDL_HAPTIC_SINE) {
        efx->type = SDL_HAPTIC_SINE;
        efx->periodic.direction.type = SDL_HAPTIC_CARTESIAN;
        efx->periodic.period = 1000;
        efx->periodic.magnitude = 0x4000;
        efx->periodic.length = 5000;
        efx->periodic.attack_length = 0;
        efx->periodic.fade_length = 0;
    } else if (haptic->supported & SDL_HAPTIC_LEFTRIGHT) {  /* XInput? */
        efx->type = SDL_HAPTIC_LEFTRIGHT;
        efx->leftright.length = 5000;
        efx->leftright.large_magnitude = 0x4000;
        efx->leftright.small_magnitude = 0x4000;
    } else {
        return SDL_SetError("Device doesn't support rumble");
    }
 
    haptic->rumble_id = SDL_HapticNewEffect(haptic, &haptic->rumble_effect);
    if (haptic->rumble_id >= 0) {
        return 0;
    }
    return -1;
}

References SDL_HapticPeriodic::attack_length, SDL_HapticPeriodic::direction, SDL_HapticPeriodic::fade_length, haptic, SDL_HapticLeftRight::large_magnitude, SDL_HapticEffect::leftright, SDL_HapticPeriodic::length, SDL_HapticLeftRight::length, SDL_HapticPeriodic::magnitude, SDL_HapticPeriodic::period, SDL_HapticEffect::periodic, SDL_HAPTIC_CARTESIAN, SDL_HAPTIC_LEFTRIGHT, SDL_HAPTIC_SINE, SDL_HapticNewEffect(), SDL_SetError, SDL_zerop, SDL_HapticLeftRight::small_magnitude, SDL_HapticDirection::type, SDL_HapticEffect::type, and ValidHaptic().

SDL_HapticRumblePlay()

int SDL_HapticRumblePlay	(	SDL_Haptic *	haptic,
		float	strength,
		Uint32	length
	)

Runs simple rumble on a haptic device.

Parameters

haptic	Haptic device to play rumble effect on.
strength	Strength of the rumble to play as a 0-1 float value.
length	Length of the rumble to play in milliseconds.

Returns

0 on success or -1 on error.

See also

SDL_HapticRumbleSupported

SDL_HapticRumbleInit

SDL_HapticRumbleStop

Definition at line 799 of file SDL_haptic.c.

{
    SDL_HapticEffect *efx;
    Sint16 magnitude;
 
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    if (haptic->rumble_id < 0) {
        return SDL_SetError("Haptic: Rumble effect not initialized on haptic device");
    }
 
    /* Clamp strength. */
    if (strength > 1.0f) {
        strength = 1.0f;
    } else if (strength < 0.0f) {
        strength = 0.0f;
    }
    magnitude = (Sint16)(32767.0f*strength);
 
    efx = &haptic->rumble_effect;
    if (efx->type == SDL_HAPTIC_SINE) {
        efx->periodic.magnitude = magnitude;
        efx->periodic.length = length;
    } else if (efx->type == SDL_HAPTIC_LEFTRIGHT) {
        efx->leftright.small_magnitude = efx->leftright.large_magnitude = magnitude;
        efx->leftright.length = length;
    } else {
        SDL_assert(0 && "This should have been caught elsewhere");
    }
 
    if (SDL_HapticUpdateEffect(haptic, haptic->rumble_id, &haptic->rumble_effect) < 0) {
        return -1;
    }
 
    return SDL_HapticRunEffect(haptic, haptic->rumble_id, 1);
}

References haptic, SDL_HapticLeftRight::large_magnitude, SDL_HapticEffect::leftright, SDL_HapticPeriodic::length, SDL_HapticLeftRight::length, SDL_HapticPeriodic::magnitude, SDL_HapticEffect::periodic, SDL_assert, SDL_HAPTIC_LEFTRIGHT, SDL_HAPTIC_SINE, SDL_HapticRunEffect(), SDL_HapticUpdateEffect(), SDL_SetError, SDL_HapticLeftRight::small_magnitude, SDL_HapticEffect::type, and ValidHaptic().

SDL_HapticRumbleStop()

int SDL_HapticRumbleStop

(

SDL_Haptic *

haptic

)

Stops the simple rumble on a haptic device.

Parameters

haptic

Haptic to stop the rumble on.

Returns

0 on success or -1 on error.

See also

SDL_HapticRumbleSupported

SDL_HapticRumbleInit

SDL_HapticRumblePlay

Definition at line 842 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    if (haptic->rumble_id < 0) {
        return SDL_SetError("Haptic: Rumble effect not initialized on haptic device");
    }
 
    return SDL_HapticStopEffect(haptic, haptic->rumble_id);
}

References haptic, SDL_HapticStopEffect(), SDL_SetError, and ValidHaptic().

SDL_HapticRumbleSupported()

int SDL_HapticRumbleSupported

(

SDL_Haptic *

haptic

)

Checks to see if rumble is supported on a haptic device.

Parameters

haptic

Haptic device to check to see if it supports rumble.

Returns

SDL_TRUE if effect is supported, SDL_FALSE if it isn't or -1 on error.

See also

SDL_HapticRumbleInit

SDL_HapticRumblePlay

SDL_HapticRumbleStop

Definition at line 743 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    /* Most things can use SINE, but XInput only has LEFTRIGHT. */
    return ((haptic->supported & (SDL_HAPTIC_SINE|SDL_HAPTIC_LEFTRIGHT)) != 0);
}

References haptic, SDL_HAPTIC_LEFTRIGHT, SDL_HAPTIC_SINE, and ValidHaptic().

SDL_HapticRunEffect()

int SDL_HapticRunEffect	(	SDL_Haptic *	haptic,
		int	effect,
		Uint32	iterations
	)

Runs the haptic effect on its associated haptic device.

If iterations are SDL_HAPTIC_INFINITY, it'll run the effect over and over repeating the envelope (attack and fade) every time. If you only want the effect to last forever, set SDL_HAPTIC_INFINITY in the effect's length parameter.

Parameters

haptic	Haptic device to run the effect on.
effect	Identifier of the haptic effect to run.
iterations	Number of iterations to run the effect. Use SDL_HAPTIC_INFINITY for infinity.

Returns

0 on success or -1 on error.

See also

SDL_HapticStopEffect

SDL_HapticDestroyEffect

SDL_HapticGetEffectStatus

Definition at line 554 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic) || !ValidEffect(haptic, effect)) {
        return -1;
    }
 
    /* Run the effect */
    if (SDL_SYS_HapticRunEffect(haptic, &haptic->effects[effect], iterations)
        < 0) {
        return -1;
    }
 
    return 0;
}

References haptic, iterations, SDL_SYS_HapticRunEffect(), ValidEffect(), and ValidHaptic().

Referenced by SDL_HapticRumblePlay().

SDL_HapticSetAutocenter()

int SDL_HapticSetAutocenter	(	SDL_Haptic *	haptic,
		int	autocenter
	)

Sets the global autocenter of the device.

Autocenter should be between 0 and 100. Setting it to 0 will disable autocentering.

Device must support the SDL_HAPTIC_AUTOCENTER feature.

Parameters

haptic	Haptic device to set autocentering on.
autocenter	Value to set autocenter to, 0 disables autocentering.

Returns

0 on success or -1 on error.

See also

SDL_HapticQuery

Definition at line 671 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    if ((haptic->supported & SDL_HAPTIC_AUTOCENTER) == 0) {
        return SDL_SetError("Haptic: Device does not support setting autocenter.");
    }
 
    if ((autocenter < 0) || (autocenter > 100)) {
        return SDL_SetError("Haptic: Autocenter must be between 0 and 100.");
    }
 
    if (SDL_SYS_HapticSetAutocenter(haptic, autocenter) < 0) {
        return -1;
    }
 
    return 0;
}

References haptic, SDL_HAPTIC_AUTOCENTER, SDL_SetError, SDL_SYS_HapticSetAutocenter(), and ValidHaptic().

Referenced by SDL_HapticOpen().

SDL_HapticSetGain()

int SDL_HapticSetGain	(	SDL_Haptic *	haptic,
		int	gain
	)

Sets the global gain of the device.

Device must support the SDL_HAPTIC_GAIN feature.

The user may specify the maximum gain by setting the environment variable SDL_HAPTIC_GAIN_MAX which should be between 0 and 100. All calls to SDL_HapticSetGain() will scale linearly using SDL_HAPTIC_GAIN_MAX as the maximum.

Parameters

haptic	Haptic device to set the gain on.
gain	Value to set the gain to, should be between 0 and 100.

Returns

0 on success or -1 on error.

See also

SDL_HapticQuery

Definition at line 626 of file SDL_haptic.c.

{
    const char *env;
    int real_gain, max_gain;
 
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    if ((haptic->supported & SDL_HAPTIC_GAIN) == 0) {
        return SDL_SetError("Haptic: Device does not support setting gain.");
    }
 
    if ((gain < 0) || (gain > 100)) {
        return SDL_SetError("Haptic: Gain must be between 0 and 100.");
    }
 
    /* We use the envvar to get the maximum gain. */
    env = SDL_getenv("SDL_HAPTIC_GAIN_MAX");
    if (env != NULL) {
        max_gain = SDL_atoi(env);
 
        /* Check for sanity. */
        if (max_gain < 0)
            max_gain = 0;
        else if (max_gain > 100)
            max_gain = 100;
 
        /* We'll scale it linearly with SDL_HAPTIC_GAIN_MAX */
        real_gain = (gain * max_gain) / 100;
    } else {
        real_gain = gain;
    }
 
    if (SDL_SYS_HapticSetGain(haptic, real_gain) < 0) {
        return -1;
    }
 
    return 0;
}

References haptic, NULL, SDL_atoi, SDL_getenv, SDL_HAPTIC_GAIN, SDL_SetError, SDL_SYS_HapticSetGain(), and ValidHaptic().

Referenced by SDL_HapticOpen().

SDL_HapticStopAll()

int SDL_HapticStopAll

(

SDL_Haptic *

haptic

)

Stops all the currently playing effects on a haptic device.

Parameters

haptic

Haptic device to stop.

Returns

0 on success or -1 on error.

Definition at line 730 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    return SDL_SYS_HapticStopAll(haptic);
}

References haptic, SDL_SYS_HapticStopAll(), and ValidHaptic().

SDL_HapticStopEffect()

int SDL_HapticStopEffect	(	SDL_Haptic *	haptic,
		int	effect
	)

Stops the haptic effect on its associated haptic device.

Parameters

haptic	Haptic device to stop the effect on.
effect	Identifier of the effect to stop.

Returns

0 on success or -1 on error.

See also

SDL_HapticRunEffect

SDL_HapticDestroyEffect

Definition at line 573 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic) || !ValidEffect(haptic, effect)) {
        return -1;
    }
 
    /* Stop the effect */
    if (SDL_SYS_HapticStopEffect(haptic, &haptic->effects[effect]) < 0) {
        return -1;
    }
 
    return 0;
}

References haptic, SDL_SYS_HapticStopEffect(), ValidEffect(), and ValidHaptic().

Referenced by SDL_HapticRumbleStop().

SDL_HapticUnpause()

int SDL_HapticUnpause

(

SDL_Haptic *

haptic

)

Unpauses a haptic device.

Call to unpause after SDL_HapticPause().

Parameters

haptic

Haptic device to unpause.

Returns

0 on success or -1 on error.

See also

SDL_HapticPause

Definition at line 713 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic)) {
        return -1;
    }
 
    if ((haptic->supported & SDL_HAPTIC_PAUSE) == 0) {
        return 0;               /* Not going to be paused, so we pretend it's unpaused. */
    }
 
    return SDL_SYS_HapticUnpause(haptic);
}

References haptic, SDL_HAPTIC_PAUSE, SDL_SYS_HapticUnpause(), and ValidHaptic().

SDL_HapticUpdateEffect()

int SDL_HapticUpdateEffect	(	SDL_Haptic *	haptic,
		int	effect,
		SDL_HapticEffect *	data
	)

Updates the properties of an effect.

Can be used dynamically, although behavior when dynamically changing direction may be strange. Specifically the effect may reupload itself and start playing from the start. You cannot change the type either when running SDL_HapticUpdateEffect().

Parameters

haptic	Haptic device that has the effect.
effect	Identifier of the effect to update.
data	New effect properties to use.

Returns

0 on success or -1 on error.

See also

SDL_HapticNewEffect

SDL_HapticRunEffect

SDL_HapticDestroyEffect

Definition at line 526 of file SDL_haptic.c.

{
    if (!ValidHaptic(haptic) || !ValidEffect(haptic, effect)) {
        return -1;
    }
 
    /* Can't change type dynamically. */
    if (data->type != haptic->effects[effect].effect.type) {
        return SDL_SetError("Haptic: Updating effect type is illegal.");
    }
 
    /* Updates the effect */
    if (SDL_SYS_HapticUpdateEffect(haptic, &haptic->effects[effect], data) <
        0) {
        return -1;
    }
 
    SDL_memcpy(&haptic->effects[effect].effect, data,
               sizeof(SDL_HapticEffect));
    return 0;
}

References haptic, SDL_memcpy, SDL_SetError, SDL_SYS_HapticUpdateEffect(), ValidEffect(), and ValidHaptic().

Referenced by SDL_HapticRumblePlay().

SDL_JoystickIsHaptic()

int SDL_JoystickIsHaptic

(

SDL_Joystick *

joystick

)

Checks to see if a joystick has haptic features.

Parameters

joystick

Joystick to test for haptic capabilities.

Returns

SDL_TRUE if the joystick is haptic, SDL_FALSE if it isn't or -1 if an error occurred.

See also

SDL_HapticOpenFromJoystick

Definition at line 248 of file SDL_haptic.c.

{
    int ret;
 
    /* Must be a valid joystick */
    if (!SDL_PrivateJoystickValid(joystick)) {
        return -1;
    }
 
    ret = SDL_SYS_JoystickIsHaptic(joystick);
 
    if (ret > 0)
        return SDL_TRUE;
    else if (ret == 0)
        return SDL_FALSE;
    else
        return -1;
}

References joystick, SDL_FALSE, SDL_PrivateJoystickValid(), SDL_SYS_JoystickIsHaptic(), and SDL_TRUE.

SDL_MouseIsHaptic()

int SDL_MouseIsHaptic

(

void

)

Gets whether or not the current mouse has haptic capabilities.

Returns

SDL_TRUE if the mouse is haptic, SDL_FALSE if it isn't.

See also

SDL_HapticOpenFromMouse

Definition at line 195 of file SDL_dynapi_procs.h.

References SDL_FALSE, SDL_SYS_HapticMouse(), and SDL_TRUE.

SDL_NumHaptics()

int SDL_NumHaptics

(

void

)

Count the number of haptic devices attached to the system.

Returns

Number of haptic devices detected on the system.

Definition at line 86 of file SDL_haptic.c.

{
    return SDL_SYS_NumHaptics();
}

References SDL_SYS_NumHaptics().

Referenced by SDL_HapticName(), SDL_HapticOpen(), SDL_HapticOpened(), and SDL_HapticOpenFromJoystick().