This repository has been archived by the owner on Feb 11, 2021. It is now read-only.
/
SDLUIAccelerationDelegate.m
142 lines (120 loc) · 4.32 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
/*
SDL - Simple DirectMedia Layer
Copyright (C) 1997-2006 Sam Lantinga
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
Sam Lantinga
slouken@libsdl.org
*/
22
23
#import "SDLUIAccelerationDelegate.h"
24
/* needed for SDL_IPHONE_MAX_GFORCE macro */
25
#import "../../../include/SDL_config_iphoneos.h"
26
27
28
29
30
static SDLUIAccelerationDelegate *sharedDelegate=nil;
@implementation SDLUIAccelerationDelegate
31
32
33
/*
Returns a shared instance of the SDLUIAccelerationDelegate, creating the shared delegate if it doesn't exist yet.
*/
34
35
36
37
38
39
+(SDLUIAccelerationDelegate *)sharedDelegate {
if (sharedDelegate == nil) {
sharedDelegate = [[SDLUIAccelerationDelegate alloc] init];
}
return sharedDelegate;
}
40
41
42
43
44
/*
UIAccelerometerDelegate delegate method. Invoked by the UIAccelerometer instance when it has new data for us.
We just take the data and mark that we have new data available so that the joystick system will pump it to the
events system when SDL_SYS_JoystickUpdate is called.
*/
45
46
47
48
49
50
-(void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration {
x = acceleration.x;
y = acceleration.y;
z = acceleration.z;
51
hasNewData = YES;
52
}
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
/*
getLastOrientation -- put last obtained accelerometer data into Sint16 array
Called from the joystick system when it needs the accelerometer data.
Function grabs the last data sent to the accelerometer and converts it
from floating point to Sint16, which is what the joystick system expects.
To do the conversion, the data is first clamped onto the interval
[-SDL_IPHONE_MAX_G_FORCE, SDL_IPHONE_MAX_G_FORCE], then the data is multiplied
by MAX_SINT16 so that it is mapped to the full range of an Sint16.
You can customize the clamped range of this function by modifying the
SDL_IPHONE_MAX_GFORCE macro in SDL_config_iphoneos.h.
Once converted to Sint16, the accelerometer data no longer has coherent units.
You can convert the data back to units of g-force by multiplying it
in your application's code by SDL_IPHONE_MAX_GFORCE / 0x7FFF.
*/
71
72
-(void)getLastOrientation:(Sint16 *)data {
73
#define MAX_SINT16 0x7FFF
74
75
/* clamp the data */
76
77
78
79
80
81
if (x > SDL_IPHONE_MAX_GFORCE) x = SDL_IPHONE_MAX_GFORCE;
else if (x < -SDL_IPHONE_MAX_GFORCE) x = -SDL_IPHONE_MAX_GFORCE;
if (y > SDL_IPHONE_MAX_GFORCE) y = SDL_IPHONE_MAX_GFORCE;
else if (y < -SDL_IPHONE_MAX_GFORCE) y = -SDL_IPHONE_MAX_GFORCE;
if (z > SDL_IPHONE_MAX_GFORCE) z = SDL_IPHONE_MAX_GFORCE;
else if (z < -SDL_IPHONE_MAX_GFORCE) z = -SDL_IPHONE_MAX_GFORCE;
82
83
/* pass in data mapped to range of SInt16 */
84
85
86
data[0] = (x / SDL_IPHONE_MAX_GFORCE) * MAX_SINT16;
data[1] = (y / SDL_IPHONE_MAX_GFORCE) * MAX_SINT16;
data[2] = (z / SDL_IPHONE_MAX_GFORCE) * MAX_SINT16;
87
88
89
}
90
91
92
93
/*
Initialize SDLUIAccelerationDelegate. Since we don't have any data yet,
just set our last received data to zero, and indicate we don't have any;
*/
94
95
96
-(id)init {
self = [super init];
x = y = z = 0.0;
97
hasNewData = NO;
98
99
100
101
102
return self;
}
-(void)dealloc {
sharedDelegate = nil;
103
[self shutdown];
104
105
106
[super dealloc];
}
107
108
109
/*
Lets our delegate start receiving accelerometer updates.
*/
110
111
112
113
-(void)startup {
[UIAccelerometer sharedAccelerometer].delegate = self;
isRunning = YES;
}
114
115
116
/*
Stops our delegate from receiving accelerometer updates.
*/
117
-(void)shutdown {
118
119
120
if ([UIAccelerometer sharedAccelerometer].delegate == self) {
[UIAccelerometer sharedAccelerometer].delegate = nil;
}
121
122
isRunning = NO;
}
123
124
125
/*
Our we currently receiving accelerometer updates?
*/
126
127
128
-(BOOL)isRunning {
return isRunning;
}
129
130
131
/*
Do we have any data that hasn't been pumped into SDL's event system?
*/
132
133
134
-(BOOL)hasNewData {
return hasNewData;
}
135
136
137
/*
When the joystick system grabs the new data, it sets this to NO.
*/
138
139
140
141
142
-(void)setHasNewData:(BOOL)value {
hasNewData = value;
}
@end