apple-fractal/GLEssentials/iOS/ViewController.m

//
//  ViewController.m
//  iOS GLEssentials
//
//  Created by Joshua Moerman on 07/03/14.
//  Copyright (c) 2014 Joshua Moerman. All rights reserved.
//

#import "ViewController.h"
#import "Game.h"

@interface ViewController () {
    Game * game;
}

@property (nonatomic) EAGLContext *context;
- (void)setupGL;
- (void)tearDownGL;
@end

@implementation ViewController

- (void)viewDidLoad{
    [super viewDidLoad];
    
    // all devices supporting ios 5 also support ES 2.0
    // only a couple of devices support ES 3.0
    self.context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
    assert(self.context);
    
    GLKView *view = (GLKView *)self.view;
    view.context = self.context;
    view.drawableDepthFormat = GLKViewDrawableDepthFormat24;
    view.drawableMultisample = GLKViewDrawableMultisampleNone;
    view.contentScaleFactor = 1.0;
    
    self.preferredFramesPerSecond = 60;
    
    [self setupGL];
}

- (void)dealloc{
    [self tearDownGL];
    
    if ([EAGLContext currentContext] == self.context) {
        [EAGLContext setCurrentContext:nil];
    }
}

- (void)didReceiveMemoryWarning{
    [super didReceiveMemoryWarning];

    if (self.isViewLoaded && (!self.view.window)) {
        self.view = nil;
        
        [self tearDownGL];
        
        if ([EAGLContext currentContext] == self.context) {
            [EAGLContext setCurrentContext:nil];
        }
        self.context = nil;
    }

    // Dispose of any resources that can be recreated.
}

- (void)setupGL{
    [EAGLContext setCurrentContext:self.context];
    game = [[Game alloc] init];
}

- (void)tearDownGL{
    [EAGLContext setCurrentContext:self.context];
    game = nil;
}

#pragma mark - GLKView and GLKViewController delegate methods

- (void)update{
    [game update:(float)self.timeSinceLastUpdate];
}

- (void)glkView:(GLKView *)view drawInRect:(CGRect)rect{
    // If we drew on a different fbo in the meantime, do this
    [((GLKView *) self.view) bindDrawable];
    
    [game draw];
}

@end