//

// ViewController.m

// CoreImageOfDong

//

// Created by Dong on 15/6/30.

// Copyright (c) 2015年 xindong. All rights reserved.

//

#import ViewController.h

#import // 需要導入此庫

@interface ViewController ()

@property (nonatomic, strong) GLKView *glkView; //渲染用的buffer視圖(類似流媒體,實時改變)

@property (nonatomic, strong) CIFilter *filter;

@property (nonatomic, strong) CIImage *ciImage;

@property (nonatomic, strong) CIContext *ciContext;

@end

 

@implementation ViewController

 

- (void)viewDidLoad {

[super viewDidLoad];

 

UIImage *showImage = [UIImage imageNamed:@demo1.jpg];

CGRect rect = CGRectMake(0, 0, showImage.size.width, showImage.size.height);

 

// 獲取OpenGLES渲染的上下文

EAGLContext *eagContext = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];

 

// 創建出渲染的buffer

self.glkView = [[GLKView alloc] initWithFrame:rect context:eagContext];

[self.glkView bindDrawable]; // 綁定繪制,否則剛開始會黑屏

[self.view addSubview:self.glkView];

 

// 創建出CoreImage用的上下文

self.ciContext = [CIContext contextWithEAGLContext:eagContext options:@{kCIContextWorkingColorSpace : [NSNull null]}];

 

// CoreImage相關設置

self.ciImage = [[CIImage alloc] initWithImage:showImage];

self.filter = [CIFilter filterWithName:@CISepiaTone];

[self.filter setValue:self.ciImage forKey:kCIInputImageKey];

[self.filter setValue:@(0) forKey:kCIInputIntensityKey];

 

// 開始渲染

[self.ciContext drawImage:[self.filter valueForKey:kCIOutputImageKey] inRect:CGRectMake(0, 0, self.glkView.drawableWidth, self.glkView.drawableHeight) fromRect:[self.ciImage extent]];

[self.glkView display];

 

// 動態渲染

UISlider *slider = [[UISlider alloc] initWithFrame:CGRectMake(30, 500, 200, 10)];

slider.minimumValue = 0.f;

slider.maximumValue = 10.f;

[slider addTarget:self action:@selector(changeColorValue:) forControlEvents:UIControlEventValueChanged];

[self.view addSubview:slider];

}

- (void)changeColorValue:(UISlider *)slider

{

[self.filter setValue:self.ciImage forKey:kCIInputImageKey];

[self.filter setValue:@(slider.value) forKey:kCIInputIntensityKey];

// 開始渲染

[self.ciContext drawImage:[self.filter valueForKey:kCIOutputImageKey] inRect:CGRectMake(0, 0, self.glkView.drawableWidth, self.glkView.drawableHeight) fromRect:[self.ciImage extent]];

[self.glkView display];

}