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Clamped values in struct ff_effect.
Added waveforms.
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@bobbens
bobbens committed Jul 1, 2008
1 parent aed0c4b commit f84a0cd
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Showing 2 changed files with 80 additions and 29 deletions.
45 changes: 37 additions & 8 deletions include/SDL_haptic.h
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Expand Up @@ -57,9 +57,38 @@ typedef struct _SDL_Haptic SDL_Haptic;
#define SDL_HAPTIC_GAIN (1<<8)
#define SDL_HAPTIC_AUTOCENTER (1<<9)

typedef enum SDL_waveform {
SDL_WAVEFORM_SINE,
SDL_WAVEFORM_SQUARE,
SDL_WAVEFORM_TRIANGLE,
SDL_WAVEFORM_SAWTOOTHUP,
SDL_WAVEFORM_SAWTOOTHDOWN
} SDL_waveform;


/*
* All values max at 32767 (0x7fff). Signed values also can be negative.
* Time values unless specified otherwise are in milliseconds.
*
* Common parts:
*
* Replay:
* Uint16 length; Duration of effect.
* Uint16 delay; Delay before starting effect.
*
* Trigger:
* Uint16 button; Button that triggers effect.
* Uint16 interval; How soon before effect can be triggered again.
*
* Envelope:
* Uint16 attack_length; Duration of the attack.
* Uint16 attack_level; Level at the start of the attack.
* Uint16 fade_length; Duration of the fade out.
* Uint16 fade_level; Level at the end of the fade.
*/
typedef struct SDL_HapticConstant {
/* Header */
Uint16 type;
Uint16 type; /* SDL_HAPTIC_CONSTANT */
Uint16 direction;

/* Replay */
Expand All @@ -71,7 +100,7 @@ typedef struct SDL_HapticConstant {
Uint16 interval;

/* Constant */
Sint16 level;
Sint16 level; /* Strength of the constant effect. */

/* Envelope */
Uint16 attack_length;
Expand All @@ -81,7 +110,7 @@ typedef struct SDL_HapticConstant {
} SDL_HapticConstant;
typedef struct SDL_HapticPeriodic {
/* Header */
Uint16 type;
Uint16 type; /* SDL_HAPTIC_PERIODIC */
Uint16 direction;

/* Replay */
Expand All @@ -93,11 +122,11 @@ typedef struct SDL_HapticPeriodic {
Uint16 interval;

/* Periodic */
Uint16 waveform;
Uint16 period;
Sint16 magnitude;
Sint16 offset;
Uint16 phase;
SDL_waveform waveform; /* Type of effect */
Uint16 period; /* Period of the wave */
Sint16 magnitude; /* Peak value */
Sint16 offset; /* Mean value of the wave */
Uint16 phase; /* Horizontal shift */

/* Envelope */
Uint16 attack_length;
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64 changes: 43 additions & 21 deletions src/haptic/linux/SDL_syshaptic.c
View file
Expand Up @@ -271,8 +271,10 @@ SDL_SYS_HapticQuit(void)
SDL_hapticlist[0].fname = NULL;
}

#define CLAMP(x) (((x) > 32767) ? 32767 : x)
/*
* Initializes the linux effect struct from a haptic_effect.
* Values above 32767 (for unsigned) are unspecified so we must clamp.
*/
static int
SDL_SYS_ToFFEffect( struct ff_effect * dest, SDL_HapticEffect * src )
Expand All @@ -289,24 +291,24 @@ SDL_SYS_ToFFEffect( struct ff_effect * dest, SDL_HapticEffect * src )

/* Header */
dest->type = FF_CONSTANT;
dest->direction = constant->direction;
dest->direction = CLAMP(constant->direction);

/* Replay */
dest->replay.length = constant->length;
dest->replay.delay = constant->delay;
dest->replay.length = CLAMP(constant->length);
dest->replay.delay = CLAMP(constant->delay);

/* Trigger */
dest->trigger.button = constant->button;
dest->trigger.interval = constant->interval;
dest->trigger.button = CLAMP(constant->button);
dest->trigger.interval = CLAMP(constant->interval);

/* Constant */
dest->u.constant.level = constant->level;

/* Envelope */
dest->u.constant.envelope.attack_length = constant->attack_length;
dest->u.constant.envelope.attack_level = constant->attack_level;
dest->u.constant.envelope.fade_length = constant->fade_length;
dest->u.constant.envelope.fade_level = constant->fade_level;
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);

break;

Expand All @@ -315,28 +317,48 @@ SDL_SYS_ToFFEffect( struct ff_effect * dest, SDL_HapticEffect * src )

/* Header */
dest->type = FF_PERIODIC;
dest->direction = periodic->direction;
dest->direction = CLAMP(periodic->direction);

/* Replay */
dest->replay.length = periodic->length;
dest->replay.delay = periodic->delay;
dest->replay.length = CLAMP(periodic->length);
dest->replay.delay = CLAMP(periodic->delay);

/* Trigger */
dest->trigger.button = periodic->button;
dest->trigger.interval = periodic->interval;
dest->trigger.button = CLAMP(periodic->button);
dest->trigger.interval = CLAMP(periodic->interval);

/* Constant */
dest->u.periodic.waveform = periodic->waveform;
dest->u.periodic.period = periodic->period;
switch (periodic->waveform) {
case SDL_WAVEFORM_SINE:
dest->u.periodic.waveform = FF_SINE;
break;
case SDL_WAVEFORM_SQUARE:
dest->u.periodic.waveform = FF_SQUARE;
break;
case SDL_WAVEFORM_TRIANGLE:
dest->u.periodic.waveform = FF_TRIANGLE;
break;
case SDL_WAVEFORM_SAWTOOTHUP:
dest->u.periodic.waveform = FF_SAW_UP;
break;
case SDL_WAVEFORM_SAWTOOTHDOWN:
dest->u.periodic.waveform = FF_SAW_DOWN;
break;

default:
SDL_SetError("Unknown waveform.");
return -1;
}
dest->u.periodic.period = CLAMP(periodic->period);
dest->u.periodic.magnitude = periodic->magnitude;
dest->u.periodic.offset = periodic->offset;
dest->u.periodic.phase = periodic->phase;
dest->u.periodic.phase = CLAMP(periodic->phase);

/* Envelope */
dest->u.periodic.envelope.attack_length = periodic->attack_length;
dest->u.periodic.envelope.attack_level = periodic->attack_level;
dest->u.periodic.envelope.fade_length = periodic->fade_length;
dest->u.periodic.envelope.fade_level = periodic->fade_level;
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);

break;

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