1 /*
2   Simple DirectMedia Layer
3   Copyright (C) 1997-2020 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_haptic.h
24  *
25  *  \brief The SDL haptic subsystem allows you to control haptic (force feedback)
26  *         devices.
27  *
28  *  The basic usage is as follows:
29  *   - Initialize the subsystem (::SDL_INIT_HAPTIC).
30  *   - Open a haptic device.
31  *    - SDL_HapticOpen() to open from index.
32  *    - SDL_HapticOpenFromJoystick() to open from an existing joystick.
33  *   - Create an effect (::SDL_HapticEffect).
34  *   - Upload the effect with SDL_HapticNewEffect().
35  *   - Run the effect with SDL_HapticRunEffect().
36  *   - (optional) Free the effect with SDL_HapticDestroyEffect().
37  *   - Close the haptic device with SDL_HapticClose().
38  *
39  * \par Simple rumble example:
40  * \code
41  *    SDL_Haptic *haptic;
42  *
43  *    // Open the device
44  *    haptic = SDL_HapticOpen( 0 );
45  *    if (haptic == NULL)
46  *       return -1;
47  *
48  *    // Initialize simple rumble
49  *    if (SDL_HapticRumbleInit( haptic ) != 0)
50  *       return -1;
51  *
52  *    // Play effect at 50% strength for 2 seconds
53  *    if (SDL_HapticRumblePlay( haptic, 0.5, 2000 ) != 0)
54  *       return -1;
55  *    SDL_Delay( 2000 );
56  *
57  *    // Clean up
58  *    SDL_HapticClose( haptic );
59  * \endcode
60  *
61  * \par Complete example:
62  * \code
63  * int test_haptic( SDL_Joystick * joystick ) {
64  *    SDL_Haptic *haptic;
65  *    SDL_HapticEffect effect;
66  *    int effect_id;
67  *
68  *    // Open the device
69  *    haptic = SDL_HapticOpenFromJoystick( joystick );
70  *    if (haptic == NULL) return -1; // Most likely joystick isn't haptic
71  *
72  *    // See if it can do sine waves
73  *    if ((SDL_HapticQuery(haptic) & SDL_HAPTIC_SINE)==0) {
74  *       SDL_HapticClose(haptic); // No sine effect
75  *       return -1;
76  *    }
77  *
78  *    // Create the effect
79  *    memset( &effect, 0, sizeof(SDL_HapticEffect) ); // 0 is safe default
80  *    effect.type = SDL_HAPTIC_SINE;
81  *    effect.periodic.direction.type = SDL_HAPTIC_POLAR; // Polar coordinates
82  *    effect.periodic.direction.dir[0] = 18000; // Force comes from south
83  *    effect.periodic.period = 1000; // 1000 ms
84  *    effect.periodic.magnitude = 20000; // 20000/32767 strength
85  *    effect.periodic.length = 5000; // 5 seconds long
86  *    effect.periodic.attack_length = 1000; // Takes 1 second to get max strength
87  *    effect.periodic.fade_length = 1000; // Takes 1 second to fade away
88  *
89  *    // Upload the effect
90  *    effect_id = SDL_HapticNewEffect( haptic, &effect );
91  *
92  *    // Test the effect
93  *    SDL_HapticRunEffect( haptic, effect_id, 1 );
94  *    SDL_Delay( 5000); // Wait for the effect to finish
95  *
96  *    // We destroy the effect, although closing the device also does this
97  *    SDL_HapticDestroyEffect( haptic, effect_id );
98  *
99  *    // Close the device
100  *    SDL_HapticClose(haptic);
101  *
102  *    return 0; // Success
103  * }
104  * \endcode
105  */
106 
107 #ifndef SDL_haptic_h_
108 #define SDL_haptic_h_
109 
110 #include "SDL_stdinc.h"
111 #include "SDL_error.h"
112 #include "SDL_joystick.h"
113 
114 #include "begin_code.h"
115 /* Set up for C function definitions, even when using C++ */
116 #ifdef __cplusplus
117 extern "C" {
118 #endif /* __cplusplus */
119 
120 /* FIXME: For SDL 2.1, adjust all the magnitude variables to be Uint16 (0xFFFF).
121  *
122  * At the moment the magnitude variables are mixed between signed/unsigned, and
123  * it is also not made clear that ALL of those variables expect a max of 0x7FFF.
124  *
125  * Some platforms may have higher precision than that (Linux FF, Windows XInput)
126  * so we should fix the inconsistency in favor of higher possible precision,
127  * adjusting for platforms that use different scales.
128  * -flibit
129  */
130 
131 /**
132  *  \typedef SDL_Haptic
133  *
134  *  \brief The haptic structure used to identify an SDL haptic.
135  *
136  *  \sa SDL_HapticOpen
137  *  \sa SDL_HapticOpenFromJoystick
138  *  \sa SDL_HapticClose
139  */
140 struct _SDL_Haptic;
141 typedef struct _SDL_Haptic SDL_Haptic;
142 
143 
144 /**
145  *  \name Haptic features
146  *
147  *  Different haptic features a device can have.
148  */
149 /* @{ */
150 
151 /**
152  *  \name Haptic effects
153  */
154 /* @{ */
155 
156 /**
157  *  \brief Constant effect supported.
158  *
159  *  Constant haptic effect.
160  *
161  *  \sa SDL_HapticCondition
162  */
163 #define SDL_HAPTIC_CONSTANT   (1u<<0)
164 
165 /**
166  *  \brief Sine wave effect supported.
167  *
168  *  Periodic haptic effect that simulates sine waves.
169  *
170  *  \sa SDL_HapticPeriodic
171  */
172 #define SDL_HAPTIC_SINE       (1u<<1)
173 
174 /**
175  *  \brief Left/Right effect supported.
176  *
177  *  Haptic effect for direct control over high/low frequency motors.
178  *
179  *  \sa SDL_HapticLeftRight
180  * \warning this value was SDL_HAPTIC_SQUARE right before 2.0.0 shipped. Sorry,
181  *          we ran out of bits, and this is important for XInput devices.
182  */
183 #define SDL_HAPTIC_LEFTRIGHT     (1u<<2)
184 
185 /* !!! FIXME: put this back when we have more bits in 2.1 */
186 /* #define SDL_HAPTIC_SQUARE     (1<<2) */
187 
188 /**
189  *  \brief Triangle wave effect supported.
190  *
191  *  Periodic haptic effect that simulates triangular waves.
192  *
193  *  \sa SDL_HapticPeriodic
194  */
195 #define SDL_HAPTIC_TRIANGLE   (1u<<3)
196 
197 /**
198  *  \brief Sawtoothup wave effect supported.
199  *
200  *  Periodic haptic effect that simulates saw tooth up waves.
201  *
202  *  \sa SDL_HapticPeriodic
203  */
204 #define SDL_HAPTIC_SAWTOOTHUP (1u<<4)
205 
206 /**
207  *  \brief Sawtoothdown wave effect supported.
208  *
209  *  Periodic haptic effect that simulates saw tooth down waves.
210  *
211  *  \sa SDL_HapticPeriodic
212  */
213 #define SDL_HAPTIC_SAWTOOTHDOWN (1u<<5)
214 
215 /**
216  *  \brief Ramp effect supported.
217  *
218  *  Ramp haptic effect.
219  *
220  *  \sa SDL_HapticRamp
221  */
222 #define SDL_HAPTIC_RAMP       (1u<<6)
223 
224 /**
225  *  \brief Spring effect supported - uses axes position.
226  *
227  *  Condition haptic effect that simulates a spring.  Effect is based on the
228  *  axes position.
229  *
230  *  \sa SDL_HapticCondition
231  */
232 #define SDL_HAPTIC_SPRING     (1u<<7)
233 
234 /**
235  *  \brief Damper effect supported - uses axes velocity.
236  *
237  *  Condition haptic effect that simulates dampening.  Effect is based on the
238  *  axes velocity.
239  *
240  *  \sa SDL_HapticCondition
241  */
242 #define SDL_HAPTIC_DAMPER     (1u<<8)
243 
244 /**
245  *  \brief Inertia effect supported - uses axes acceleration.
246  *
247  *  Condition haptic effect that simulates inertia.  Effect is based on the axes
248  *  acceleration.
249  *
250  *  \sa SDL_HapticCondition
251  */
252 #define SDL_HAPTIC_INERTIA    (1u<<9)
253 
254 /**
255  *  \brief Friction effect supported - uses axes movement.
256  *
257  *  Condition haptic effect that simulates friction.  Effect is based on the
258  *  axes movement.
259  *
260  *  \sa SDL_HapticCondition
261  */
262 #define SDL_HAPTIC_FRICTION   (1u<<10)
263 
264 /**
265  *  \brief Custom effect is supported.
266  *
267  *  User defined custom haptic effect.
268  */
269 #define SDL_HAPTIC_CUSTOM     (1u<<11)
270 
271 /* @} *//* Haptic effects */
272 
273 /* These last few are features the device has, not effects */
274 
275 /**
276  *  \brief Device can set global gain.
277  *
278  *  Device supports setting the global gain.
279  *
280  *  \sa SDL_HapticSetGain
281  */
282 #define SDL_HAPTIC_GAIN       (1u<<12)
283 
284 /**
285  *  \brief Device can set autocenter.
286  *
287  *  Device supports setting autocenter.
288  *
289  *  \sa SDL_HapticSetAutocenter
290  */
291 #define SDL_HAPTIC_AUTOCENTER (1u<<13)
292 
293 /**
294  *  \brief Device can be queried for effect status.
295  *
296  *  Device supports querying effect status.
297  *
298  *  \sa SDL_HapticGetEffectStatus
299  */
300 #define SDL_HAPTIC_STATUS     (1u<<14)
301 
302 /**
303  *  \brief Device can be paused.
304  *
305  *  Devices supports being paused.
306  *
307  *  \sa SDL_HapticPause
308  *  \sa SDL_HapticUnpause
309  */
310 #define SDL_HAPTIC_PAUSE      (1u<<15)
311 
312 
313 /**
314  * \name Direction encodings
315  */
316 /* @{ */
317 
318 /**
319  *  \brief Uses polar coordinates for the direction.
320  *
321  *  \sa SDL_HapticDirection
322  */
323 #define SDL_HAPTIC_POLAR      0
324 
325 /**
326  *  \brief Uses cartesian coordinates for the direction.
327  *
328  *  \sa SDL_HapticDirection
329  */
330 #define SDL_HAPTIC_CARTESIAN  1
331 
332 /**
333  *  \brief Uses spherical coordinates for the direction.
334  *
335  *  \sa SDL_HapticDirection
336  */
337 #define SDL_HAPTIC_SPHERICAL  2
338 
339 /**
340  *  \brief Use this value to play an effect on the steering wheel axis. This
341  *  provides better compatibility across platforms and devices as SDL will guess
342  *  the correct axis.
343  *  \sa SDL_HapticDirection
344  */
345 #define SDL_HAPTIC_STEERING_AXIS 3
346 
347 /* @} *//* Direction encodings */
348 
349 /* @} *//* Haptic features */
350 
351 /*
352  * Misc defines.
353  */
354 
355 /**
356  * \brief Used to play a device an infinite number of times.
357  *
358  * \sa SDL_HapticRunEffect
359  */
360 #define SDL_HAPTIC_INFINITY   4294967295U
361 
362 
363 /**
364  *  \brief Structure that represents a haptic direction.
365  *
366  *  This is the direction where the force comes from,
367  *  instead of the direction in which the force is exerted.
368  *
369  *  Directions can be specified by:
370  *   - ::SDL_HAPTIC_POLAR : Specified by polar coordinates.
371  *   - ::SDL_HAPTIC_CARTESIAN : Specified by cartesian coordinates.
372  *   - ::SDL_HAPTIC_SPHERICAL : Specified by spherical coordinates.
373  *
374  *  Cardinal directions of the haptic device are relative to the positioning
375  *  of the device.  North is considered to be away from the user.
376  *
377  *  The following diagram represents the cardinal directions:
378  *  \verbatim
379                  .--.
380                  |__| .-------.
381                  |=.| |.-----.|
382                  |--| ||     ||
383                  |  | |'-----'|
384                  |__|~')_____('
385                    [ COMPUTER ]
386 
387 
388                      North (0,-1)
389                          ^
390                          |
391                          |
392    (-1,0)  West <----[ HAPTIC ]----> East (1,0)
393                          |
394                          |
395                          v
396                       South (0,1)
397 
398 
399                       [ USER ]
400                         \|||/
401                         (o o)
402                   ---ooO-(_)-Ooo---
403     \endverbatim
404  *
405  *  If type is ::SDL_HAPTIC_POLAR, direction is encoded by hundredths of a
406  *  degree starting north and turning clockwise.  ::SDL_HAPTIC_POLAR only uses
407  *  the first \c dir parameter.  The cardinal directions would be:
408  *   - North: 0 (0 degrees)
409  *   - East: 9000 (90 degrees)
410  *   - South: 18000 (180 degrees)
411  *   - West: 27000 (270 degrees)
412  *
413  *  If type is ::SDL_HAPTIC_CARTESIAN, direction is encoded by three positions
414  *  (X axis, Y axis and Z axis (with 3 axes)).  ::SDL_HAPTIC_CARTESIAN uses
415  *  the first three \c dir parameters.  The cardinal directions would be:
416  *   - North:  0,-1, 0
417  *   - East:   1, 0, 0
418  *   - South:  0, 1, 0
419  *   - West:  -1, 0, 0
420  *
421  *  The Z axis represents the height of the effect if supported, otherwise
422  *  it's unused.  In cartesian encoding (1, 2) would be the same as (2, 4), you
423  *  can use any multiple you want, only the direction matters.
424  *
425  *  If type is ::SDL_HAPTIC_SPHERICAL, direction is encoded by two rotations.
426  *  The first two \c dir parameters are used.  The \c dir parameters are as
427  *  follows (all values are in hundredths of degrees):
428  *   - Degrees from (1, 0) rotated towards (0, 1).
429  *   - Degrees towards (0, 0, 1) (device needs at least 3 axes).
430  *
431  *
432  *  Example of force coming from the south with all encodings (force coming
433  *  from the south means the user will have to pull the stick to counteract):
434  *  \code
435  *  SDL_HapticDirection direction;
436  *
437  *  // Cartesian directions
438  *  direction.type = SDL_HAPTIC_CARTESIAN; // Using cartesian direction encoding.
439  *  direction.dir[0] = 0; // X position
440  *  direction.dir[1] = 1; // Y position
441  *  // Assuming the device has 2 axes, we don't need to specify third parameter.
442  *
443  *  // Polar directions
444  *  direction.type = SDL_HAPTIC_POLAR; // We'll be using polar direction encoding.
445  *  direction.dir[0] = 18000; // Polar only uses first parameter
446  *
447  *  // Spherical coordinates
448  *  direction.type = SDL_HAPTIC_SPHERICAL; // Spherical encoding
449  *  direction.dir[0] = 9000; // Since we only have two axes we don't need more parameters.
450  *  \endcode
451  *
452  *  \sa SDL_HAPTIC_POLAR
453  *  \sa SDL_HAPTIC_CARTESIAN
454  *  \sa SDL_HAPTIC_SPHERICAL
455  *  \sa SDL_HAPTIC_STEERING_AXIS
456  *  \sa SDL_HapticEffect
457  *  \sa SDL_HapticNumAxes
458  */
459 typedef struct SDL_HapticDirection
460 {
461     Uint8 type;         /**< The type of encoding. */
462     Sint32 dir[3];      /**< The encoded direction. */
463 } SDL_HapticDirection;
464 
465 
466 /**
467  *  \brief A structure containing a template for a Constant effect.
468  *
469  *  This struct is exclusively for the ::SDL_HAPTIC_CONSTANT effect.
470  *
471  *  A constant effect applies a constant force in the specified direction
472  *  to the joystick.
473  *
474  *  \sa SDL_HAPTIC_CONSTANT
475  *  \sa SDL_HapticEffect
476  */
477 typedef struct SDL_HapticConstant
478 {
479     /* Header */
480     Uint16 type;            /**< ::SDL_HAPTIC_CONSTANT */
481     SDL_HapticDirection direction;  /**< Direction of the effect. */
482 
483     /* Replay */
484     Uint32 length;          /**< Duration of the effect. */
485     Uint16 delay;           /**< Delay before starting the effect. */
486 
487     /* Trigger */
488     Uint16 button;          /**< Button that triggers the effect. */
489     Uint16 interval;        /**< How soon it can be triggered again after button. */
490 
491     /* Constant */
492     Sint16 level;           /**< Strength of the constant effect. */
493 
494     /* Envelope */
495     Uint16 attack_length;   /**< Duration of the attack. */
496     Uint16 attack_level;    /**< Level at the start of the attack. */
497     Uint16 fade_length;     /**< Duration of the fade. */
498     Uint16 fade_level;      /**< Level at the end of the fade. */
499 } SDL_HapticConstant;
500 
501 /**
502  *  \brief A structure containing a template for a Periodic effect.
503  *
504  *  The struct handles the following effects:
505  *   - ::SDL_HAPTIC_SINE
506  *   - ::SDL_HAPTIC_LEFTRIGHT
507  *   - ::SDL_HAPTIC_TRIANGLE
508  *   - ::SDL_HAPTIC_SAWTOOTHUP
509  *   - ::SDL_HAPTIC_SAWTOOTHDOWN
510  *
511  *  A periodic effect consists in a wave-shaped effect that repeats itself
512  *  over time.  The type determines the shape of the wave and the parameters
513  *  determine the dimensions of the wave.
514  *
515  *  Phase is given by hundredth of a degree meaning that giving the phase a value
516  *  of 9000 will displace it 25% of its period.  Here are sample values:
517  *   -     0: No phase displacement.
518  *   -  9000: Displaced 25% of its period.
519  *   - 18000: Displaced 50% of its period.
520  *   - 27000: Displaced 75% of its period.
521  *   - 36000: Displaced 100% of its period, same as 0, but 0 is preferred.
522  *
523  *  Examples:
524  *  \verbatim
525     SDL_HAPTIC_SINE
526       __      __      __      __
527      /  \    /  \    /  \    /
528     /    \__/    \__/    \__/
529 
530     SDL_HAPTIC_SQUARE
531      __    __    __    __    __
532     |  |  |  |  |  |  |  |  |  |
533     |  |__|  |__|  |__|  |__|  |
534 
535     SDL_HAPTIC_TRIANGLE
536       /\    /\    /\    /\    /\
537      /  \  /  \  /  \  /  \  /
538     /    \/    \/    \/    \/
539 
540     SDL_HAPTIC_SAWTOOTHUP
541       /|  /|  /|  /|  /|  /|  /|
542      / | / | / | / | / | / | / |
543     /  |/  |/  |/  |/  |/  |/  |
544 
545     SDL_HAPTIC_SAWTOOTHDOWN
546     \  |\  |\  |\  |\  |\  |\  |
547      \ | \ | \ | \ | \ | \ | \ |
548       \|  \|  \|  \|  \|  \|  \|
549     \endverbatim
550  *
551  *  \sa SDL_HAPTIC_SINE
552  *  \sa SDL_HAPTIC_LEFTRIGHT
553  *  \sa SDL_HAPTIC_TRIANGLE
554  *  \sa SDL_HAPTIC_SAWTOOTHUP
555  *  \sa SDL_HAPTIC_SAWTOOTHDOWN
556  *  \sa SDL_HapticEffect
557  */
558 typedef struct SDL_HapticPeriodic
559 {
560     /* Header */
561     Uint16 type;        /**< ::SDL_HAPTIC_SINE, ::SDL_HAPTIC_LEFTRIGHT,
562                              ::SDL_HAPTIC_TRIANGLE, ::SDL_HAPTIC_SAWTOOTHUP or
563                              ::SDL_HAPTIC_SAWTOOTHDOWN */
564     SDL_HapticDirection direction;  /**< Direction of the effect. */
565 
566     /* Replay */
567     Uint32 length;      /**< Duration of the effect. */
568     Uint16 delay;       /**< Delay before starting the effect. */
569 
570     /* Trigger */
571     Uint16 button;      /**< Button that triggers the effect. */
572     Uint16 interval;    /**< How soon it can be triggered again after button. */
573 
574     /* Periodic */
575     Uint16 period;      /**< Period of the wave. */
576     Sint16 magnitude;   /**< Peak value; if negative, equivalent to 180 degrees extra phase shift. */
577     Sint16 offset;      /**< Mean value of the wave. */
578     Uint16 phase;       /**< Positive phase shift given by hundredth of a degree. */
579 
580     /* Envelope */
581     Uint16 attack_length;   /**< Duration of the attack. */
582     Uint16 attack_level;    /**< Level at the start of the attack. */
583     Uint16 fade_length; /**< Duration of the fade. */
584     Uint16 fade_level;  /**< Level at the end of the fade. */
585 } SDL_HapticPeriodic;
586 
587 /**
588  *  \brief A structure containing a template for a Condition effect.
589  *
590  *  The struct handles the following effects:
591  *   - ::SDL_HAPTIC_SPRING: Effect based on axes position.
592  *   - ::SDL_HAPTIC_DAMPER: Effect based on axes velocity.
593  *   - ::SDL_HAPTIC_INERTIA: Effect based on axes acceleration.
594  *   - ::SDL_HAPTIC_FRICTION: Effect based on axes movement.
595  *
596  *  Direction is handled by condition internals instead of a direction member.
597  *  The condition effect specific members have three parameters.  The first
598  *  refers to the X axis, the second refers to the Y axis and the third
599  *  refers to the Z axis.  The right terms refer to the positive side of the
600  *  axis and the left terms refer to the negative side of the axis.  Please
601  *  refer to the ::SDL_HapticDirection diagram for which side is positive and
602  *  which is negative.
603  *
604  *  \sa SDL_HapticDirection
605  *  \sa SDL_HAPTIC_SPRING
606  *  \sa SDL_HAPTIC_DAMPER
607  *  \sa SDL_HAPTIC_INERTIA
608  *  \sa SDL_HAPTIC_FRICTION
609  *  \sa SDL_HapticEffect
610  */
611 typedef struct SDL_HapticCondition
612 {
613     /* Header */
614     Uint16 type;            /**< ::SDL_HAPTIC_SPRING, ::SDL_HAPTIC_DAMPER,
615                                  ::SDL_HAPTIC_INERTIA or ::SDL_HAPTIC_FRICTION */
616     SDL_HapticDirection direction;  /**< Direction of the effect - Not used ATM. */
617 
618     /* Replay */
619     Uint32 length;          /**< Duration of the effect. */
620     Uint16 delay;           /**< Delay before starting the effect. */
621 
622     /* Trigger */
623     Uint16 button;          /**< Button that triggers the effect. */
624     Uint16 interval;        /**< How soon it can be triggered again after button. */
625 
626     /* Condition */
627     Uint16 right_sat[3];    /**< Level when joystick is to the positive side; max 0xFFFF. */
628     Uint16 left_sat[3];     /**< Level when joystick is to the negative side; max 0xFFFF. */
629     Sint16 right_coeff[3];  /**< How fast to increase the force towards the positive side. */
630     Sint16 left_coeff[3];   /**< How fast to increase the force towards the negative side. */
631     Uint16 deadband[3];     /**< Size of the dead zone; max 0xFFFF: whole axis-range when 0-centered. */
632     Sint16 center[3];       /**< Position of the dead zone. */
633 } SDL_HapticCondition;
634 
635 /**
636  *  \brief A structure containing a template for a Ramp effect.
637  *
638  *  This struct is exclusively for the ::SDL_HAPTIC_RAMP effect.
639  *
640  *  The ramp effect starts at start strength and ends at end strength.
641  *  It augments in linear fashion.  If you use attack and fade with a ramp
642  *  the effects get added to the ramp effect making the effect become
643  *  quadratic instead of linear.
644  *
645  *  \sa SDL_HAPTIC_RAMP
646  *  \sa SDL_HapticEffect
647  */
648 typedef struct SDL_HapticRamp
649 {
650     /* Header */
651     Uint16 type;            /**< ::SDL_HAPTIC_RAMP */
652     SDL_HapticDirection direction;  /**< Direction of the effect. */
653 
654     /* Replay */
655     Uint32 length;          /**< Duration of the effect. */
656     Uint16 delay;           /**< Delay before starting the effect. */
657 
658     /* Trigger */
659     Uint16 button;          /**< Button that triggers the effect. */
660     Uint16 interval;        /**< How soon it can be triggered again after button. */
661 
662     /* Ramp */
663     Sint16 start;           /**< Beginning strength level. */
664     Sint16 end;             /**< Ending strength level. */
665 
666     /* Envelope */
667     Uint16 attack_length;   /**< Duration of the attack. */
668     Uint16 attack_level;    /**< Level at the start of the attack. */
669     Uint16 fade_length;     /**< Duration of the fade. */
670     Uint16 fade_level;      /**< Level at the end of the fade. */
671 } SDL_HapticRamp;
672 
673 /**
674  * \brief A structure containing a template for a Left/Right effect.
675  *
676  * This struct is exclusively for the ::SDL_HAPTIC_LEFTRIGHT effect.
677  *
678  * The Left/Right effect is used to explicitly control the large and small
679  * motors, commonly found in modern game controllers. The small (right) motor
680  * is high frequency, and the large (left) motor is low frequency.
681  *
682  * \sa SDL_HAPTIC_LEFTRIGHT
683  * \sa SDL_HapticEffect
684  */
685 typedef struct SDL_HapticLeftRight
686 {
687     /* Header */
688     Uint16 type;            /**< ::SDL_HAPTIC_LEFTRIGHT */
689 
690     /* Replay */
691     Uint32 length;          /**< Duration of the effect in milliseconds. */
692 
693     /* Rumble */
694     Uint16 large_magnitude; /**< Control of the large controller motor. */
695     Uint16 small_magnitude; /**< Control of the small controller motor. */
696 } SDL_HapticLeftRight;
697 
698 /**
699  *  \brief A structure containing a template for the ::SDL_HAPTIC_CUSTOM effect.
700  *
701  *  This struct is exclusively for the ::SDL_HAPTIC_CUSTOM effect.
702  *
703  *  A custom force feedback effect is much like a periodic effect, where the
704  *  application can define its exact shape.  You will have to allocate the
705  *  data yourself.  Data should consist of channels * samples Uint16 samples.
706  *
707  *  If channels is one, the effect is rotated using the defined direction.
708  *  Otherwise it uses the samples in data for the different axes.
709  *
710  *  \sa SDL_HAPTIC_CUSTOM
711  *  \sa SDL_HapticEffect
712  */
713 typedef struct SDL_HapticCustom
714 {
715     /* Header */
716     Uint16 type;            /**< ::SDL_HAPTIC_CUSTOM */
717     SDL_HapticDirection direction;  /**< Direction of the effect. */
718 
719     /* Replay */
720     Uint32 length;          /**< Duration of the effect. */
721     Uint16 delay;           /**< Delay before starting the effect. */
722 
723     /* Trigger */
724     Uint16 button;          /**< Button that triggers the effect. */
725     Uint16 interval;        /**< How soon it can be triggered again after button. */
726 
727     /* Custom */
728     Uint8 channels;         /**< Axes to use, minimum of one. */
729     Uint16 period;          /**< Sample periods. */
730     Uint16 samples;         /**< Amount of samples. */
731     Uint16 *data;           /**< Should contain channels*samples items. */
732 
733     /* Envelope */
734     Uint16 attack_length;   /**< Duration of the attack. */
735     Uint16 attack_level;    /**< Level at the start of the attack. */
736     Uint16 fade_length;     /**< Duration of the fade. */
737     Uint16 fade_level;      /**< Level at the end of the fade. */
738 } SDL_HapticCustom;
739 
740 /**
741  *  \brief The generic template for any haptic effect.
742  *
743  *  All values max at 32767 (0x7FFF).  Signed values also can be negative.
744  *  Time values unless specified otherwise are in milliseconds.
745  *
746  *  You can also pass ::SDL_HAPTIC_INFINITY to length instead of a 0-32767
747  *  value.  Neither delay, interval, attack_length nor fade_length support
748  *  ::SDL_HAPTIC_INFINITY.  Fade will also not be used since effect never ends.
749  *
750  *  Additionally, the ::SDL_HAPTIC_RAMP effect does not support a duration of
751  *  ::SDL_HAPTIC_INFINITY.
752  *
753  *  Button triggers may not be supported on all devices, it is advised to not
754  *  use them if possible.  Buttons start at index 1 instead of index 0 like
755  *  the joystick.
756  *
757  *  If both attack_length and fade_level are 0, the envelope is not used,
758  *  otherwise both values are used.
759  *
760  *  Common parts:
761  *  \code
762  *  // Replay - All effects have this
763  *  Uint32 length;        // Duration of effect (ms).
764  *  Uint16 delay;         // Delay before starting effect.
765  *
766  *  // Trigger - All effects have this
767  *  Uint16 button;        // Button that triggers effect.
768  *  Uint16 interval;      // How soon before effect can be triggered again.
769  *
770  *  // Envelope - All effects except condition effects have this
771  *  Uint16 attack_length; // Duration of the attack (ms).
772  *  Uint16 attack_level;  // Level at the start of the attack.
773  *  Uint16 fade_length;   // Duration of the fade out (ms).
774  *  Uint16 fade_level;    // Level at the end of the fade.
775  *  \endcode
776  *
777  *
778  *  Here we have an example of a constant effect evolution in time:
779  *  \verbatim
780     Strength
781     ^
782     |
783     |    effect level -->  _________________
784     |                     /                 \
785     |                    /                   \
786     |                   /                     \
787     |                  /                       \
788     | attack_level --> |                        \
789     |                  |                        |  <---  fade_level
790     |
791     +--------------------------------------------------> Time
792                        [--]                 [---]
793                        attack_length        fade_length
794 
795     [------------------][-----------------------]
796     delay               length
797     \endverbatim
798  *
799  *  Note either the attack_level or the fade_level may be above the actual
800  *  effect level.
801  *
802  *  \sa SDL_HapticConstant
803  *  \sa SDL_HapticPeriodic
804  *  \sa SDL_HapticCondition
805  *  \sa SDL_HapticRamp
806  *  \sa SDL_HapticLeftRight
807  *  \sa SDL_HapticCustom
808  */
809 typedef union SDL_HapticEffect
810 {
811     /* Common for all force feedback effects */
812     Uint16 type;                    /**< Effect type. */
813     SDL_HapticConstant constant;    /**< Constant effect. */
814     SDL_HapticPeriodic periodic;    /**< Periodic effect. */
815     SDL_HapticCondition condition;  /**< Condition effect. */
816     SDL_HapticRamp ramp;            /**< Ramp effect. */
817     SDL_HapticLeftRight leftright;  /**< Left/Right effect. */
818     SDL_HapticCustom custom;        /**< Custom effect. */
819 } SDL_HapticEffect;
820 
821 
822 /* Function prototypes */
823 /**
824  *  \brief Count the number of haptic devices attached to the system.
825  *
826  *  \return Number of haptic devices detected on the system.
827  */
828 extern DECLSPEC int SDLCALL SDL_NumHaptics(void);
829 
830 /**
831  *  \brief Get the implementation dependent name of a haptic device.
832  *
833  *  This can be called before any joysticks are opened.
834  *  If no name can be found, this function returns NULL.
835  *
836  *  \param device_index Index of the device to get its name.
837  *  \return Name of the device or NULL on error.
838  *
839  *  \sa SDL_NumHaptics
840  */
841 extern DECLSPEC const char *SDLCALL SDL_HapticName(int device_index);
842 
843 /**
844  *  \brief Opens a haptic device for use.
845  *
846  *  The index passed as an argument refers to the N'th haptic device on this
847  *  system.
848  *
849  *  When opening a haptic device, its gain will be set to maximum and
850  *  autocenter will be disabled.  To modify these values use
851  *  SDL_HapticSetGain() and SDL_HapticSetAutocenter().
852  *
853  *  \param device_index Index of the device to open.
854  *  \return Device identifier or NULL on error.
855  *
856  *  \sa SDL_HapticIndex
857  *  \sa SDL_HapticOpenFromMouse
858  *  \sa SDL_HapticOpenFromJoystick
859  *  \sa SDL_HapticClose
860  *  \sa SDL_HapticSetGain
861  *  \sa SDL_HapticSetAutocenter
862  *  \sa SDL_HapticPause
863  *  \sa SDL_HapticStopAll
864  */
865 extern DECLSPEC SDL_Haptic *SDLCALL SDL_HapticOpen(int device_index);
866 
867 /**
868  *  \brief Checks if the haptic device at index has been opened.
869  *
870  *  \param device_index Index to check to see if it has been opened.
871  *  \return 1 if it has been opened or 0 if it hasn't.
872  *
873  *  \sa SDL_HapticOpen
874  *  \sa SDL_HapticIndex
875  */
876 extern DECLSPEC int SDLCALL SDL_HapticOpened(int device_index);
877 
878 /**
879  *  \brief Gets the index of a haptic device.
880  *
881  *  \param haptic Haptic device to get the index of.
882  *  \return The index of the haptic device or -1 on error.
883  *
884  *  \sa SDL_HapticOpen
885  *  \sa SDL_HapticOpened
886  */
887 extern DECLSPEC int SDLCALL SDL_HapticIndex(SDL_Haptic * haptic);
888 
889 /**
890  *  \brief Gets whether or not the current mouse has haptic capabilities.
891  *
892  *  \return SDL_TRUE if the mouse is haptic, SDL_FALSE if it isn't.
893  *
894  *  \sa SDL_HapticOpenFromMouse
895  */
896 extern DECLSPEC int SDLCALL SDL_MouseIsHaptic(void);
897 
898 /**
899  *  \brief Tries to open a haptic device from the current mouse.
900  *
901  *  \return The haptic device identifier or NULL on error.
902  *
903  *  \sa SDL_MouseIsHaptic
904  *  \sa SDL_HapticOpen
905  */
906 extern DECLSPEC SDL_Haptic *SDLCALL SDL_HapticOpenFromMouse(void);
907 
908 /**
909  *  \brief Checks to see if a joystick has haptic features.
910  *
911  *  \param joystick Joystick to test for haptic capabilities.
912  *  \return SDL_TRUE if the joystick is haptic, SDL_FALSE if it isn't
913  *          or -1 if an error occurred.
914  *
915  *  \sa SDL_HapticOpenFromJoystick
916  */
917 extern DECLSPEC int SDLCALL SDL_JoystickIsHaptic(SDL_Joystick * joystick);
918 
919 /**
920  *  \brief Opens a haptic device for use from a joystick device.
921  *
922  *  You must still close the haptic device separately.  It will not be closed
923  *  with the joystick.
924  *
925  *  When opening from a joystick you should first close the haptic device before
926  *  closing the joystick device.  If not, on some implementations the haptic
927  *  device will also get unallocated and you'll be unable to use force feedback
928  *  on that device.
929  *
930  *  \param joystick Joystick to create a haptic device from.
931  *  \return A valid haptic device identifier on success or NULL on error.
932  *
933  *  \sa SDL_HapticOpen
934  *  \sa SDL_HapticClose
935  */
936 extern DECLSPEC SDL_Haptic *SDLCALL SDL_HapticOpenFromJoystick(SDL_Joystick *
937                                                                joystick);
938 
939 /**
940  *  \brief Closes a haptic device previously opened with SDL_HapticOpen().
941  *
942  *  \param haptic Haptic device to close.
943  */
944 extern DECLSPEC void SDLCALL SDL_HapticClose(SDL_Haptic * haptic);
945 
946 /**
947  *  \brief Returns the number of effects a haptic device can store.
948  *
949  *  On some platforms this isn't fully supported, and therefore is an
950  *  approximation.  Always check to see if your created effect was actually
951  *  created and do not rely solely on SDL_HapticNumEffects().
952  *
953  *  \param haptic The haptic device to query effect max.
954  *  \return The number of effects the haptic device can store or
955  *          -1 on error.
956  *
957  *  \sa SDL_HapticNumEffectsPlaying
958  *  \sa SDL_HapticQuery
959  */
960 extern DECLSPEC int SDLCALL SDL_HapticNumEffects(SDL_Haptic * haptic);
961 
962 /**
963  *  \brief Returns the number of effects a haptic device can play at the same
964  *         time.
965  *
966  *  This is not supported on all platforms, but will always return a value.
967  *  Added here for the sake of completeness.
968  *
969  *  \param haptic The haptic device to query maximum playing effects.
970  *  \return The number of effects the haptic device can play at the same time
971  *          or -1 on error.
972  *
973  *  \sa SDL_HapticNumEffects
974  *  \sa SDL_HapticQuery
975  */
976 extern DECLSPEC int SDLCALL SDL_HapticNumEffectsPlaying(SDL_Haptic * haptic);
977 
978 /**
979  *  \brief Gets the haptic device's supported features in bitwise manner.
980  *
981  *  Example:
982  *  \code
983  *  if (SDL_HapticQuery(haptic) & SDL_HAPTIC_CONSTANT) {
984  *      printf("We have constant haptic effect!\n");
985  *  }
986  *  \endcode
987  *
988  *  \param haptic The haptic device to query.
989  *  \return Haptic features in bitwise manner (OR'd).
990  *
991  *  \sa SDL_HapticNumEffects
992  *  \sa SDL_HapticEffectSupported
993  */
994 extern DECLSPEC unsigned int SDLCALL SDL_HapticQuery(SDL_Haptic * haptic);
995 
996 
997 /**
998  *  \brief Gets the number of haptic axes the device has.
999  *
1000  *  \sa SDL_HapticDirection
1001  */
1002 extern DECLSPEC int SDLCALL SDL_HapticNumAxes(SDL_Haptic * haptic);
1003 
1004 /**
1005  *  \brief Checks to see if effect is supported by haptic.
1006  *
1007  *  \param haptic Haptic device to check on.
1008  *  \param effect Effect to check to see if it is supported.
1009  *  \return SDL_TRUE if effect is supported, SDL_FALSE if it isn't or -1 on error.
1010  *
1011  *  \sa SDL_HapticQuery
1012  *  \sa SDL_HapticNewEffect
1013  */
1014 extern DECLSPEC int SDLCALL SDL_HapticEffectSupported(SDL_Haptic * haptic,
1015                                                       SDL_HapticEffect *
1016                                                       effect);
1017 
1018 /**
1019  *  \brief Creates a new haptic effect on the device.
1020  *
1021  *  \param haptic Haptic device to create the effect on.
1022  *  \param effect Properties of the effect to create.
1023  *  \return The identifier of the effect on success or -1 on error.
1024  *
1025  *  \sa SDL_HapticUpdateEffect
1026  *  \sa SDL_HapticRunEffect
1027  *  \sa SDL_HapticDestroyEffect
1028  */
1029 extern DECLSPEC int SDLCALL SDL_HapticNewEffect(SDL_Haptic * haptic,
1030                                                 SDL_HapticEffect * effect);
1031 
1032 /**
1033  *  \brief Updates the properties of an effect.
1034  *
1035  *  Can be used dynamically, although behavior when dynamically changing
1036  *  direction may be strange.  Specifically the effect may reupload itself
1037  *  and start playing from the start.  You cannot change the type either when
1038  *  running SDL_HapticUpdateEffect().
1039  *
1040  *  \param haptic Haptic device that has the effect.
1041  *  \param effect Identifier of the effect to update.
1042  *  \param data New effect properties to use.
1043  *  \return 0 on success or -1 on error.
1044  *
1045  *  \sa SDL_HapticNewEffect
1046  *  \sa SDL_HapticRunEffect
1047  *  \sa SDL_HapticDestroyEffect
1048  */
1049 extern DECLSPEC int SDLCALL SDL_HapticUpdateEffect(SDL_Haptic * haptic,
1050                                                    int effect,
1051                                                    SDL_HapticEffect * data);
1052 
1053 /**
1054  *  \brief Runs the haptic effect on its associated haptic device.
1055  *
1056  *  If iterations are ::SDL_HAPTIC_INFINITY, it'll run the effect over and over
1057  *  repeating the envelope (attack and fade) every time.  If you only want the
1058  *  effect to last forever, set ::SDL_HAPTIC_INFINITY in the effect's length
1059  *  parameter.
1060  *
1061  *  \param haptic Haptic device to run the effect on.
1062  *  \param effect Identifier of the haptic effect to run.
1063  *  \param iterations Number of iterations to run the effect. Use
1064  *         ::SDL_HAPTIC_INFINITY for infinity.
1065  *  \return 0 on success or -1 on error.
1066  *
1067  *  \sa SDL_HapticStopEffect
1068  *  \sa SDL_HapticDestroyEffect
1069  *  \sa SDL_HapticGetEffectStatus
1070  */
1071 extern DECLSPEC int SDLCALL SDL_HapticRunEffect(SDL_Haptic * haptic,
1072                                                 int effect,
1073                                                 Uint32 iterations);
1074 
1075 /**
1076  *  \brief Stops the haptic effect on its associated haptic device.
1077  *
1078  *  \param haptic Haptic device to stop the effect on.
1079  *  \param effect Identifier of the effect to stop.
1080  *  \return 0 on success or -1 on error.
1081  *
1082  *  \sa SDL_HapticRunEffect
1083  *  \sa SDL_HapticDestroyEffect
1084  */
1085 extern DECLSPEC int SDLCALL SDL_HapticStopEffect(SDL_Haptic * haptic,
1086                                                  int effect);
1087 
1088 /**
1089  *  \brief Destroys a haptic effect on the device.
1090  *
1091  *  This will stop the effect if it's running.  Effects are automatically
1092  *  destroyed when the device is closed.
1093  *
1094  *  \param haptic Device to destroy the effect on.
1095  *  \param effect Identifier of the effect to destroy.
1096  *
1097  *  \sa SDL_HapticNewEffect
1098  */
1099 extern DECLSPEC void SDLCALL SDL_HapticDestroyEffect(SDL_Haptic * haptic,
1100                                                      int effect);
1101 
1102 /**
1103  *  \brief Gets the status of the current effect on the haptic device.
1104  *
1105  *  Device must support the ::SDL_HAPTIC_STATUS feature.
1106  *
1107  *  \param haptic Haptic device to query the effect status on.
1108  *  \param effect Identifier of the effect to query its status.
1109  *  \return 0 if it isn't playing, 1 if it is playing or -1 on error.
1110  *
1111  *  \sa SDL_HapticRunEffect
1112  *  \sa SDL_HapticStopEffect
1113  */
1114 extern DECLSPEC int SDLCALL SDL_HapticGetEffectStatus(SDL_Haptic * haptic,
1115                                                       int effect);
1116 
1117 /**
1118  *  \brief Sets the global gain of the device.
1119  *
1120  *  Device must support the ::SDL_HAPTIC_GAIN feature.
1121  *
1122  *  The user may specify the maximum gain by setting the environment variable
1123  *  SDL_HAPTIC_GAIN_MAX which should be between 0 and 100.  All calls to
1124  *  SDL_HapticSetGain() will scale linearly using SDL_HAPTIC_GAIN_MAX as the
1125  *  maximum.
1126  *
1127  *  \param haptic Haptic device to set the gain on.
1128  *  \param gain Value to set the gain to, should be between 0 and 100.
1129  *  \return 0 on success or -1 on error.
1130  *
1131  *  \sa SDL_HapticQuery
1132  */
1133 extern DECLSPEC int SDLCALL SDL_HapticSetGain(SDL_Haptic * haptic, int gain);
1134 
1135 /**
1136  *  \brief Sets the global autocenter of the device.
1137  *
1138  *  Autocenter should be between 0 and 100.  Setting it to 0 will disable
1139  *  autocentering.
1140  *
1141  *  Device must support the ::SDL_HAPTIC_AUTOCENTER feature.
1142  *
1143  *  \param haptic Haptic device to set autocentering on.
1144  *  \param autocenter Value to set autocenter to, 0 disables autocentering.
1145  *  \return 0 on success or -1 on error.
1146  *
1147  *  \sa SDL_HapticQuery
1148  */
1149 extern DECLSPEC int SDLCALL SDL_HapticSetAutocenter(SDL_Haptic * haptic,
1150                                                     int autocenter);
1151 
1152 /**
1153  *  \brief Pauses a haptic device.
1154  *
1155  *  Device must support the ::SDL_HAPTIC_PAUSE feature.  Call
1156  *  SDL_HapticUnpause() to resume playback.
1157  *
1158  *  Do not modify the effects nor add new ones while the device is paused.
1159  *  That can cause all sorts of weird errors.
1160  *
1161  *  \param haptic Haptic device to pause.
1162  *  \return 0 on success or -1 on error.
1163  *
1164  *  \sa SDL_HapticUnpause
1165  */
1166 extern DECLSPEC int SDLCALL SDL_HapticPause(SDL_Haptic * haptic);
1167 
1168 /**
1169  *  \brief Unpauses a haptic device.
1170  *
1171  *  Call to unpause after SDL_HapticPause().
1172  *
1173  *  \param haptic Haptic device to unpause.
1174  *  \return 0 on success or -1 on error.
1175  *
1176  *  \sa SDL_HapticPause
1177  */
1178 extern DECLSPEC int SDLCALL SDL_HapticUnpause(SDL_Haptic * haptic);
1179 
1180 /**
1181  *  \brief Stops all the currently playing effects on a haptic device.
1182  *
1183  *  \param haptic Haptic device to stop.
1184  *  \return 0 on success or -1 on error.
1185  */
1186 extern DECLSPEC int SDLCALL SDL_HapticStopAll(SDL_Haptic * haptic);
1187 
1188 /**
1189  *  \brief Checks to see if rumble is supported on a haptic device.
1190  *
1191  *  \param haptic Haptic device to check to see if it supports rumble.
1192  *  \return SDL_TRUE if effect is supported, SDL_FALSE if it isn't or -1 on error.
1193  *
1194  *  \sa SDL_HapticRumbleInit
1195  *  \sa SDL_HapticRumblePlay
1196  *  \sa SDL_HapticRumbleStop
1197  */
1198 extern DECLSPEC int SDLCALL SDL_HapticRumbleSupported(SDL_Haptic * haptic);
1199 
1200 /**
1201  *  \brief Initializes the haptic device for simple rumble playback.
1202  *
1203  *  \param haptic Haptic device to initialize for simple rumble playback.
1204  *  \return 0 on success or -1 on error.
1205  *
1206  *  \sa SDL_HapticOpen
1207  *  \sa SDL_HapticRumbleSupported
1208  *  \sa SDL_HapticRumblePlay
1209  *  \sa SDL_HapticRumbleStop
1210  */
1211 extern DECLSPEC int SDLCALL SDL_HapticRumbleInit(SDL_Haptic * haptic);
1212 
1213 /**
1214  *  \brief Runs simple rumble on a haptic device
1215  *
1216  *  \param haptic Haptic device to play rumble effect on.
1217  *  \param strength Strength of the rumble to play as a 0-1 float value.
1218  *  \param length Length of the rumble to play in milliseconds.
1219  *  \return 0 on success or -1 on error.
1220  *
1221  *  \sa SDL_HapticRumbleSupported
1222  *  \sa SDL_HapticRumbleInit
1223  *  \sa SDL_HapticRumbleStop
1224  */
1225 extern DECLSPEC int SDLCALL SDL_HapticRumblePlay(SDL_Haptic * haptic, float strength, Uint32 length );
1226 
1227 /**
1228  *  \brief Stops the simple rumble on a haptic device.
1229  *
1230  *  \param haptic Haptic to stop the rumble on.
1231  *  \return 0 on success or -1 on error.
1232  *
1233  *  \sa SDL_HapticRumbleSupported
1234  *  \sa SDL_HapticRumbleInit
1235  *  \sa SDL_HapticRumblePlay
1236  */
1237 extern DECLSPEC int SDLCALL SDL_HapticRumbleStop(SDL_Haptic * haptic);
1238 
1239 /* Ends C function definitions when using C++ */
1240 #ifdef __cplusplus
1241 }
1242 #endif
1243 #include "close_code.h"
1244 
1245 #endif /* SDL_haptic_h_ */
1246 
1247 /* vi: set ts=4 sw=4 expandtab: */
1248