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import UIKit

// Returns a list of points on the convex hull in counter-clockwise order.
// Note: the last point in the returned list is the same as the first one.
//
// https://en.wikibooks.org/wiki/Algorithm_Implementation/Geometry/Convex_hull/Monotone_chain
//
func closedConvexHull(points_ : [CGPoint]) -> [CGPoint] {
    
    // 2D cross product of OA and OB vectors, i.e. z-component of their 3D cross product.

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import Foundation
import SceneKit

class Icosahedron : Geometry {
    // The golden ratio
    static let t = (1.0 + sqrt(5.0)) / 2.0;
    
    // These vertices represent three orthogonal rectangles
    // The corners of which define the 12 vertices of an icosahedron
    // We get the normalized vector so that our points are on the unit sphere

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function retry(isDone, next) {
    var current_trial = 0, max_retry = 50, interval = 10, is_timeout = false;
    var id = window.setInterval(
        function() {
            if (isDone()) {
                window.clearInterval(id);
                next(is_timeout);
            }
            if (current_trial++ > max_retry) {
                window.clearInterval(id);

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//
//  SimpleScrollingStack.swift
//  A super-simple demo of a scrolling UIStackView in iOS 9
//
//  Created by Paul Hudson on 10/06/2015.
//  Learn Swift at www.hackingwithswift.com
//  @twostraws
//

import UIKit

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FILE SPACING:

 # double space a file
 sed G

 # double space a file which already has blank lines in it. Output file
 # should contain no more than one blank line between lines of text.
 sed '/^$/d;G'

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public struct Credentials {
    
    public init(key: String, secret: String) {
        self.key = key
        self.secret = secret
    }
    
    public let key: String
    public let secret: String
}

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⇐ back to the gist-blog at jrw.fi

Advanced SCSS

Or, 16 cool things you may not have known your stylesheets could do. I'd rather have kept it to a nice round number like 10, but they just kept coming. Sorry.

I've been using SCSS/SASS for most of my styling work since 2009, and I'm a huge fan of Compass (by the great @chriseppstein). It really helped many of us through the darkest cross-browser crap. Even though browsers are increasingly playing nice with CSS, another problem has become very topical: managing the complexity in stylesheets as our in-browser apps get larger and larger. SCSS is an indispensable tool for dealing with this.

This isn't an introduction to the language by a long shot; many things probably won't make sense unless you have some SCSS under your belt already. That said, if you're not yet comfy with the basics, check out the aweso

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