January 6, 2013
I recently saw a post on Twitter from @chpwn that described the alogorithm that Apple uses for its “rubber band” or “bungee” scrolling.
b = (1.0 – (1.0 / ((x * c / d) + 1.0))) * d
self.startButton.rac_command = [RACCommand command]; | |
self.stopButton.rac_command = [RACCommand command]; | |
self.resetButton.rac_command = [RACCommand command]; | |
static const CGFloat interval = 0.01; | |
__unsafe_unretained id weakSelf = self; | |
// Signal id -> Signal Signal Number | |
// Map each click of the start button to a signal that fires at our interval | |
// and stops when the stop button's clicked. | |
id<RACSignal> start = [self.startButton.rac_command map:^(id _) { |
// when setting the position of a layer, use this: | |
// layer.position = [ layer pixelAlignedPostionForPoint:<originalPoint> ] ; | |
@implementation CALayer (SetPositionPixelAligned) | |
-(CGPoint)pixelAlignedPositionForPoint:(CGPoint)p | |
{ | |
CGSize size = self.bounds.size ; | |
CGPoint anchorPoint = self.anchorPoint ; | |
// Taken from the commercial iOS PDF framework http://pspdfkit.com. | |
// Copyright (c) 2014 Peter Steinberger, PSPDFKit GmbH. All rights reserved. | |
// Licensed under MIT (http://opensource.org/licenses/MIT) | |
// | |
// You should only use this in debug builds. It doesn't use private API, but I wouldn't ship it. | |
// PLEASE DUPE rdar://27192338 (https://openradar.appspot.com/27192338) if you would like to see this in UIKit. | |
#import <objc/runtime.h> | |
#import <objc/message.h> |
// Defines a yet undocumented method to add a warning if super isn't called. | |
#ifndef NS_REQUIRES_SUPER | |
#if __has_attribute(objc_requires_super) | |
#define NS_REQUIRES_SUPER __attribute((objc_requires_super)) | |
#else | |
#define NS_REQUIRES_SUPER | |
#endif | |
#endif |
// Taken from http://PSPDFKit.com. This snippet is under public domain. | |
#define UIKitVersionNumber_iOS_7_0 0xB57 | |
BOOL PSPDFIsUIKitFlatMode(void) { | |
static BOOL isUIKitFlatMode = NO; | |
static dispatch_once_t onceToken; | |
dispatch_once(&onceToken, ^{ | |
// We get the modern UIKit if system is running >= iOS 7 and we were linked with >= SDK 7. | |
if (kCFCoreFoundationVersionNumber >= kCFCoreFoundationVersionNumber_iOS_7_0) { | |
isUIKitFlatMode = (NSVersionOfLinkTimeLibrary("UIKit") >> 16) >= UIKitVersionNumber_iOS_7_0; | |
} |
#ifndef NS_DESIGNATED_INITIALIZER | |
#if __has_attribute(objc_designated_initializer) | |
#define NS_DESIGNATED_INITIALIZER __attribute((objc_designated_initializer)) | |
#else | |
#define NS_DESIGNATED_INITIALIZER | |
#endif | |
#endif |
// | |
// Created by Tony Arnold on 4/03/2014. | |
// Copyright (c) 2014 The CocoaBots. All rights reserved. | |
// | |
#import "NSView+TCBAdditions.h" | |
#import <objc/runtime.h> | |
@implementation NSView (TCBAdditions) |
func encode<T>(var value: T) -> NSData { | |
return withUnsafePointer(&value) { p in | |
NSData(bytes: p, length: sizeofValue(value)) | |
} | |
} | |
func decode<T>(data: NSData) -> T { | |
let pointer = UnsafeMutablePointer<T>.alloc(sizeof(T.Type)) | |
data.getBytes(pointer) | |
// A type-level SAT solver in Swift | |
// Two types to model Booleans | |
struct True { } | |
struct False { } | |
// Negation, Conjunction, Disjunction |