Next, using the ‘Add Other’ button, navigate to your downloaded NinevehGL folder and import the NinevehGL.framework. 
Now onto the code…….import NinevehGL into your header (.h) file, #import <NinevehGL/NinevehGL.h> add the delegate to your @interface, if this is missing your drawview method will never get called. @interface ViewController : UIViewController <NGLViewDelegate>; In order to see what is being rendered we will need an ivar for an NGLCamera, and for our single object, an NGLMesh. The complete code for all of this should look as follows. #import <UIKit/UIKit.h>#import <NinevehGL/NinevehGL.h> @interface ViewController : UIViewController <NGLViewDelegate> { NGLCamera *_camera; NGLMesh *_mesh; }In your source (.m) file you must initialize your NGLView, set its delgate to self, define a dictionary with a few basic settings, and initialize the mesh and camera. I am doing this in my viewDidLoad method but depending on your needs, this could be done elsewhere.
- (void)viewDidLoad{ [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. // Setup our NGLView. NGLView *theView = [[NGLView alloc] initWithFrame:CGRectMake(40, 40, 240, 360)]; // Set its delegate to self so the drawview method is used. theView.delegate = self; // Add the new view on top of our existing view. [self.view addSubview:theView]; // The content scale factor is used to increase the resolution to take advantage of retina displays and values range from 1.0 to 2.0. This sets the contentscalefactor to the max screen scale of the device. theView.contentScaleFactor = [[UIScreen mainScreen] scale]; // Setup some initial environment states to be applied to our mesh. NSDictionary *settings = [NSDictionary dictionaryWithObjectsAndKeys: kNGLMeshCentralizeYes, kNGLMeshKeyCentralize, @"0.3", kNGLMeshKeyNormalize, nil]; // Initialize the mesh which includes the model file to import (.obj or .dae). _mesh = [[NGLMesh alloc] initWithFile:@"earth.obj" settings:settings delegate:nil]; // Initialize the camera used to render the scene. _camera = [[NGLCamera alloc] initWithMeshes:_mesh, nil]; // If a trasparent background of the NGLView is needed //theView.backgroundColor = [UIColor clearColor]; //nglGlobalColorFormat(NGLColorFormatRGBA); //nglGlobalFlush(); // The following command displays a 3d view status monitor that will show your current frame rate and number of polygons being rendered in the view. [[NGLDebug debugMonitor] startWithView:(NGLView *)self.view];}You will need to add at least one method to your source (.m) file, this is the drawView loop. This drawView loop is used to generate each frame being displayed (up to 60 per second). This drawloop is where you would affect the mesh to animate movement or create the effects your a looking to display. The [_camera drawCamera] is needed to commit the changes and render the frame. The method usually ends with this command.
-(void)drawView{ // Rotate on Y axis _mesh.rotateY += .5; // Draw to our camera to display on our view [_camera drawCamera];} In the above example, the _mesh.rotateY += .5 is used to rotate the mesh .5 degrees each time the frame is rendered. Now build and run the project and you should see a slowly spinning planet Earth. The NGLView was purposely drawn smaller than the background view in order to show how you could overlay this NGLView over any other normal view to add 3D content. If you want the background of the NGLView to be transparent, set the background color of the view to clear and add the following additional commands. There is also a status monitor that can be run to display frame rates and the number of polygons being rendered for optimization. 
// If a trasparent background of the NGLView is needed theView.backgroundColor = [UIColor clearColor]; nglGlobalColorFormat(NGLColorFormatRGBA); nglGlobalFlush();// The following command displays a 3d view status monitor that will show your current frame rate and number of polygons being rendered in the view. [[NGLDebug debugMonitor] startWithView:(NGLView *)self.view];There are many commands you can use to affect your object, it’s movement and how it interacts in it’s 3D environment, here are just a few basic ones. Advanced animation, movement techniques, object hit testing, custom shaders, etc. would be worthy of a separate tutorial. Enjoy.
// rotation _mesh.rotateX, rotateY, rotateZ// scaling _mesh.scaleX, scaleY, scaleZ // placement _mesh.x,y,z // offset center of objects rotation _mesh.pivot = nglVec3Make(x, y, z)Assets Project file Awake & Evolve Workout of the Day Mature Athlete Workout of the Day Mommy Workout of the Day RKC Kettlebell Workout of the Day Strength & Conditioning Workout of the Day Sport Specific Workout of the Day Women's Workout of the Day
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