NJInputAnalog.m

   1 //
   2 //  NJInputAnalog.m
   3 //  Enjoy
   4 //
   5 //  Created by Sam McCall on 5/05/09.
   6 //
   7
   8 #define DEAD_ZONE 0.3
   9
  10 #import "NJInputAnalog.h"
  11
  12 static float normalize(long p, long min, long max) {
  13     return 2 * (p - min) / (float)(max - min) - 1;
  14 }
  15
  16 @implementation NJInputAnalog {
  17     float magnitude;
  18     long rawMin;
  19     long rawMax;
  20 }
  21
  22 - (id)initWithIndex:(int)index rawMin:(long)rawMin_ rawMax:(long)rawMax_ {
  23     if ((self = [super init])) {
  24         self.name = [[NSString alloc] initWithFormat: @"Axis %d", index];
  25         self.children = @[[[NJInput alloc] initWithName:@"Low" base:self],
  26                           [[NJInput alloc] initWithName:@"High" base:self]];
  27         rawMax = rawMax_;
  28         rawMin = rawMin_;
  29     }
  30     return self;
  31 }
  32
  33 - (id)findSubInputForValue:(IOHIDValueRef)value {
  34     float mag = normalize(IOHIDValueGetIntegerValue(value), rawMin, rawMax);
  35     if (mag < -DEAD_ZONE)
  36         return self.children[0];
  37     else if (mag > DEAD_ZONE)
  38         return self.children[1];
  39     else
  40         return nil;
  41 }
  42
  43 - (void)notifyEvent:(IOHIDValueRef)value {
  44     magnitude = normalize(IOHIDValueGetIntegerValue(value), rawMin, rawMax);
  45     [self.children[0] setMagnitude:fabsf(MIN(magnitude, 0))];
  46     [self.children[1] setMagnitude:fabsf(MAX(magnitude, 0))];
  47     [self.children[0] setActive:magnitude < -DEAD_ZONE];
  48     [self.children[1] setActive:magnitude > DEAD_ZONE];
  49 }
  50
  51 - (float)magnitude {
  52     return magnitude;
  53 }
  54
  55 @end