gistfile1.swift

//
//  CGViewController.swift
//  Banksy
//
//  Created by Shayne Sweeney on 11/1/14.
//  Copyright (c) 2014 App Couture. All rights reserved.
//

import UIKit

class CGViewController: UIViewController {
    var alpha: Float = 1
    let imageView = UIImageView()
    
    let shirtMask = UIImage(named: "tshirt-mask")!
    let shirtShadows = UIImage(named: "tshirt-shadows")!
    let shirtHighlights = UIImage(named: "tshirt-highlights")!
    
    var text = "I feel pretty, oh so pretty"
    
    var shirtSize: CGSize {
        get {
            return self.shirtMask.size
        }
    }
    
    var shirtRect: CGRect {
        get {
            return CGRectMake(0.0, 0.0, self.shirtSize.width, self.shirtSize.height)
        }
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        imageView.frame = view.bounds
        imageView.contentMode = UIViewContentMode.ScaleAspectFit
        view.addSubview(imageView)
        
        let textField = UITextField(frame: CGRectMake(30, 30, 290, 30))
        textField.text = text
        textField.addTarget(self, action: "onTextFieldUpdate:", forControlEvents: .EditingChanged)
        view.addSubview(textField)
        
        renderShirt()
    }
    
    func onTextFieldUpdate(textField: UITextField) {
        text = textField.text
        renderShirt()
    }
    
    func renderShirt() {
        UIGraphicsBeginImageContextWithOptions(shirtSize, false, 0)
        
        // clip
        CGContextScaleCTM(UIGraphicsGetCurrentContext(), 1.0, -1.0)
        CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0.0, -shirtRect.size.height)
        CGContextClipToMask(UIGraphicsGetCurrentContext(), shirtRect, shirtMask.CGImage)
        CGContextScaleCTM(UIGraphicsGetCurrentContext(), 1.0, -1.0)
        CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0.0, -shirtRect.size.height)
        
        // fill the shirt color
//        UIColor(white: 0.5, alpha: 1).setFill()
        UIColor(red: 109/255, green: 108/255, blue: 108/255, alpha: 1.0).setFill()
//        UIColor(red: 1, green: 0, blue: 0, alpha: 0.99).setFill()
        CGContextSetBlendMode(UIGraphicsGetCurrentContext(), kCGBlendModeNormal)
        CGContextFillRect(UIGraphicsGetCurrentContext(), shirtRect)
        
        // render text
        renderTextImage().drawAtPoint(CGPointMake(110, 40), blendMode: kCGBlendModeNormal, alpha: 0.99)
        
        // draw the highlights and shadows
        shirtHighlights.drawAtPoint(CGPointZero, blendMode: kCGBlendModeHardLight, alpha: 0.7)
        shirtShadows.drawAtPoint(CGPointZero, blendMode: kCGBlendModeHardLight, alpha: 0.7)
        
        imageView.image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
    }
    
    func renderTextImage() -> UIImage {
        let label = UILabel()
        label.text = text
        label.font = UIFont(name: "F25 Executive", size: 50)
        label.textColor = UIColor(white: 1, alpha: 1)
        label.numberOfLines = 3
        
        let rect = CGRectMake(0, 0, 320, 320)
        
        UIGraphicsBeginImageContextWithOptions(rect.size, false, 0)
        
        label.drawTextInRect(rect)
        
        let textImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        
        UIGraphicsBeginImageContextWithOptions(shirtSize, false, 0)
        
        // clip
        CGContextScaleCTM(UIGraphicsGetCurrentContext(), 1.0, -1.0)
        CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0.0, -rect.size.height)
        CGContextClipToMask(UIGraphicsGetCurrentContext(), rect, textImage.CGImage)
        CGContextScaleCTM(UIGraphicsGetCurrentContext(), 1.0, -1.0)
        CGContextTranslateCTM(UIGraphicsGetCurrentContext(), 0.0, -rect.size.height)
        
        // draw the highlights and shadows
        shirtHighlights.drawAtPoint(CGPointZero, blendMode: kCGBlendModeHardLight, alpha: 0.99)
        shirtShadows.drawAtPoint(CGPointZero, blendMode: kCGBlendModeHardLight, alpha: 0.99)
        
        textImage.drawAtPoint(CGPointZero, blendMode: kCGBlendModeNormal, alpha: 0.99)
        
        let output = UIGraphicsGetImageFromCurrentImageContext()
        
        UIGraphicsEndImageContext()
        
        return output
    }
}