//

// RRFPSBar.m

//

// Created by Rolandas Razma on 07/03/2013.

// Copyright 2013 Rolandas Razma. All rights reserved.

//

// Permission is hereby granted, free of charge, to any person

// obtaining a copy of this software and associated documentation

// files (the "Software"), to deal in the Software without

// restriction, including without limitation the rights to use,

// copy, modify, merge, publish, distribute, sublicense, and/or sell

// copies of the Software, and to permit persons to whom the

// Software is furnished to do so, subject to the following

// conditions:

//

// The above copyright notice and this permission notice shall be

// included in all copies or substantial portions of the Software.

//

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

// OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

// WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

// OTHER DEALINGS IN THE SOFTWARE.

//

#import "RRFPSBar.h"

#import <QuartzCore/QuartzCore.h>

@implementation RRFPSBar {

CADisplayLink *_displayLink;

NSUInteger _historyDTLength;

NSUInteger _maxHistoryDTLength;

CFTimeInterval *_historyDT;

CFTimeInterval _displayLinkTickTimeLast;

CFTimeInterval _lastUIUpdateTime;

CATextLayer *_fpsTextLayer;

CAShapeLayer *_linesLayer;

CAShapeLayer *_chartLayer;

BOOL _showsAverage;

}

#pragma mark -

#pragma mark NSObject

- (void)dealloc {

[_displayLink setPaused:YES];

[_displayLink removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];

free(_historyDT);

}

- (id)init {

if( (self = [super initWithFrame:[[UIApplication sharedApplication] statusBarFrame]]) ){

_maxHistoryDTLength = (NSInteger)CGRectGetWidth(self.bounds);

_historyDT = malloc(sizeof(CFTimeInterval) * _maxHistoryDTLength);

_historyDTLength = 0;

_displayLinkTickTimeLast= CACurrentMediaTime();

[self setWindowLevel: UIWindowLevelStatusBar +1.0f];

[self setBackgroundColor:[UIColor clearColor]];

[[NSNotificationCenter defaultCenter] addObserver: self

selector: @selector(applicationDidBecomeActiveNotification)

name: UIApplicationDidBecomeActiveNotification

object: nil];

[[NSNotificationCenter defaultCenter] addObserver: self

selector: @selector(applicationWillResignActiveNotification)

name: UIApplicationWillResignActiveNotification

object: nil];

// Track FPS using display link

_displayLink = [CADisplayLink displayLinkWithTarget:self selector:@selector(displayLinkTick)];

[_displayLink setPaused:YES];

[_displayLink addToRunLoop:[NSRunLoop currentRunLoop] forMode:NSRunLoopCommonModes];

// Lines Layer

_linesLayer = [CAShapeLayer layer];

[_linesLayer setFrame: self.bounds];

[_linesLayer setStrokeColor:[UIColor colorWithRed:1.0f green:1.0f blue:1.0f alpha:0.5f].CGColor];

[_linesLayer setContentsScale: [UIScreen mainScreen].scale];

UIBezierPath *path = [UIBezierPath bezierPath];

[path moveToPoint:CGPointMake(0.0f, self.frame.size.height)];

[path addLineToPoint:CGPointMake(self.frame.size.width, self.frame.size.height)];

[path closePath];

[_linesLayer setPath:path.CGPath];

[self.layer addSublayer:_linesLayer];

// Chart Layer

_chartLayer = [CAShapeLayer layer];

[_chartLayer setFrame: self.bounds];

[_chartLayer setStrokeColor: [UIColor redColor].CGColor];

[_chartLayer setContentsScale: [UIScreen mainScreen].scale];

[self.layer addSublayer:_chartLayer];

// Info Layer

_fpsTextLayer = [CATextLayer layer];

[_fpsTextLayer setFrame: CGRectMake(CGRectGetWidth(self.bounds) - 120, 0, 120.0f, self.bounds.size.height)];

[_fpsTextLayer setFont:CGFontCreateWithFontName((CFStringRef)[UIFont boldSystemFontOfSize:12].fontName)];

[_fpsTextLayer setFontSize: 12.0f];

[_fpsTextLayer setForegroundColor: [UIColor redColor].CGColor];

[_fpsTextLayer setAlignmentMode:kCAAlignmentCenter];

[_fpsTextLayer setBackgroundColor:[UIColor colorWithWhite:0 alpha:0.8].CGColor];

[_fpsTextLayer setContentsScale: [UIScreen mainScreen].scale];

[self.layer addSublayer:_fpsTextLayer];

// Draw asynchronously on iOS6+

if( [_chartLayer respondsToSelector:@selector(setDrawsAsynchronously:)] ){

[_linesLayer setDrawsAsynchronously:YES];

[_chartLayer setDrawsAsynchronously:YES];

[_fpsTextLayer setDrawsAsynchronously:YES];

}

[self setDesiredChartUpdateInterval: 1.0f /60.0f];

}

return self;

}

#pragma mark -

#pragma mark RRFPSBar

+ (RRFPSBar *)sharedInstance {

static RRFPSBar *_sharedInstance;

static dispatch_once_t onceToken;

dispatch_once(&onceToken, ^{

_sharedInstance = [[RRFPSBar alloc] init];

if([[UIDevice currentDevice].systemVersion floatValue] >= 9.0)

_sharedInstance.rootViewController = [UIViewController new]; // iOS 9 requires rootViewController for any window

});

return _sharedInstance;

}

- (void)applicationDidBecomeActiveNotification {

[_displayLink setPaused:NO];

}

- (void)applicationWillResignActiveNotification {

[_displayLink setPaused:YES];

}

- (void)becomeKeyWindow{//prevent self to be key window

self.hidden = YES;

dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(1.0 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{

self.hidden = NO;

});

}

- (void)displayLinkTick {

// Shift up the buffer

for (NSUInteger i = _historyDTLength; i >= 1; i-- ) {

_historyDT[i] = _historyDT[i -1];

}

// Store new state

_historyDT[0] = _displayLink.timestamp -_displayLinkTickTimeLast;

// Update length if there is more place

if ( _historyDTLength < _maxHistoryDTLength - 1) _historyDTLength++;

// Store last timestamp

_displayLinkTickTimeLast = _displayLink.timestamp;

// Update UI

CFTimeInterval timeSinceLastUIUpdate = _displayLinkTickTimeLast -_lastUIUpdateTime;

if( _historyDT[0] < 0.1f && timeSinceLastUIUpdate >= _desiredChartUpdateInterval ){

[self updateChartAndText];

}

}

- (void)updateChartAndText {

UIBezierPath *path = [UIBezierPath bezierPath];

[path moveToPoint:CGPointZero];

CFTimeInterval maxDT = CGFLOAT_MIN;

CFTimeInterval avgDT = 0.0f;

for( NSUInteger i=0; i<=_historyDTLength; i++ ){

maxDT = MAX(maxDT, _historyDT[i]);

avgDT += _historyDT[i];

CGFloat fraction = roundf(1.0f /(float)_historyDT[i]) /60.0f;

CGFloat y = _chartLayer.frame.size.height -_chartLayer.frame.size.height *fraction;

y = MAX(0.0f, MIN(_chartLayer.frame.size.height, y));

[path addLineToPoint:CGPointMake(i +1.0f, y)];

}

[path addLineToPoint:CGPointMake(_historyDTLength, 0)];

avgDT /= _historyDTLength;

_chartLayer.path = path.CGPath;

CFTimeInterval minFPS = roundf(1.0f /(float)maxDT);

CFTimeInterval avgFPS = roundf(1.0f /(float)avgDT);

NSString *text;

if( _showsAverage ){

text = [NSString stringWithFormat:@"low: %.f | avg: %.f", minFPS, avgFPS];

} else {

text = [NSString stringWithFormat:@"low %.f", minFPS];

}

[_fpsTextLayer setString: text];

_lastUIUpdateTime = _displayLinkTickTimeLast;

}

@end