/*

     File: GLGravityView.h

 Abstract: This class wraps the CAEAGLLayer from CoreAnimation into a convenient

 UIView subclass. The view content is basically an EAGL surface you render your

 OpenGL scene into.  Note that setting the view non-opaque will only work if the

 EAGL surface has an alpha channel.

  Version: 2.2

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*/

#import <UIKit/UIKit.h>

#import <OpenGLES/EAGL.h>

#import <OpenGLES/ES1/gl.h>

#import <OpenGLES/ES1/glext.h>

@interface GLGravityView : UIView

{

@private

    // The pixel dimensions of the backbuffer

    GLint backingWidth;

    GLint backingHeight;

    EAGLContext *context;

    // OpenGL names for the renderbuffer and framebuffers used to render to this view

    GLuint viewRenderbuffer, viewFramebuffer;

    // OpenGL name for the depth buffer that is attached to viewFramebuffer, if it exists (0 if it does not exist)

    GLuint depthRenderbuffer;

    BOOL animating;

    BOOL displayLinkSupported;

    NSInteger animationFrameInterval;

    // Use of the CADisplayLink class is the preferred method for controlling your animation timing.

    // CADisplayLink will link to the main display and fire every vsync when added to a given run-loop.

    // The NSTimer class is used only as fallback when running on a pre 3.1 device where CADisplayLink

    // isn't available.

    id displayLink;

    NSTimer *animationTimer;

    UIAccelerationValue *accel;

}

@property (readonly, nonatomic, getter=isAnimating) BOOL animating;

@property (nonatomic) NSInteger animationFrameInterval;

@property (nonatomic) UIAccelerationValue *accel;

-(void)startAnimation;

-(void)stopAnimation;

-(void)drawView;

@end