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/**

 *  @file SurfaceView.h

 *  A View that implements a CoreSurface buffer

 *  The buffer is created automatically in initWithFrame: with the size

 *  passed to it and 5-6-5 RGB format.

 *  The memory can be accessed with the pixels property, and after modifying

 *  it you must call setNeedsDisplay on it for it to update.

 */

 

#import <UIKit/UIKit.h>

#import <CoreSurface/CoreSurface.h>

 

@interface SurfaceView : UIView

{

    CALayer *surfaceLayer;

    unsigned short *pixels;

    CoreSurfaceBufferRef surfaceBuffer;

}

 

@property (nonatomic, readonly) unsigned short *pixels;

 

@end

 

 

 

/**

 *  @file SurfaceView.m

 *  Implementation of SurfaceView

 */

 

#import "SurfaceView.h"

 

@implementation SurfaceView

 

- (id)initWithFrame:(CGRect)frame {

    frame.origin.x /= 2;

    frame.origin.y /= 2;

   

    if (self = [super initWithFrame:frame]) {

        // Create Surface

        int w = frame.size.width, h = frame.size.height;

        surfaceBuffer = CoreSurfaceBufferCreate((CFDictionaryRef)[NSDictionary dictionaryWithObjectsAndKeys:

            [NSNumber numberWithInt:w],         kCoreSurfaceBufferWidth,

            [NSNumber numberWithInt:h],         kCoreSurfaceBufferHeight,

            [NSNumber numberWithInt:'L565'],    kCoreSurfaceBufferPixelFormat,

            [NSNumber numberWithInt:2*w*h],     kCoreSurfaceBufferAllocSize,

            [NSNumber numberWithBool:YES],      kCoreSurfaceBufferGlobal,

            [NSNumber numberWithInt:2*w],       kCoreSurfaceBufferPitch,

            @"PurpleGFXMem",                    kCoreSurfaceBufferMemoryRegion,

            nil]);

       

        // Create layer for surface

        CGRect frame2 = CGRectMake(frame.origin.x, frame.origin.y,

                                   frame.size.width+1, frame.size.height+1);

        CoreSurfaceBufferLock(surfaceBuffer, 3);

        surfaceLayer = [[CALayer layer] retain];

        [surfaceLayer setMagnificationFilter:0];

        [surfaceLayer setEdgeAntialiasingMask:0];

        [surfaceLayer setFrame:frame2];

        [surfaceLayer setContents:surfaceBuffer];

        [surfaceLayer setOpaque:YES];

        [[self _layer] addSublayer:surfaceLayer];

        CoreSurfaceBufferUnlock(surfaceBuffer);

       

        // Get base address

        pixels = CoreSurfaceBufferGetBaseAddress(surfaceBuffer);

    }

    return self;

}

 

- (void)dealloc {

    [surfaceLayer release];

    [super dealloc];

}

 

- (void)drawRect:(CGRect)rect {

    // It will break if you remove this empty function

}

 

- (unsigned short*)pixels {

    return pixels;

}

@end

/** 

 *  @file SurfaceView.h

 *  A View that implements a CoreSurface buffer

 *  The buffer is created automatically in initWithFrame: with the size

 *  passed to it and 5-6-5 RGB format.

 *  The memory can be accessed with the pixels property, and after modifying

 *  it you must call setNeedsDisplay on it for it to update.

 */

 

#import <UIKit/UIKit.h>

#import <CoreSurface/CoreSurface.h>

@interface SurfaceView : UIView 

{

    CALayer *surfaceLayer;

    unsigned short *pixels;

    CoreSurfaceBufferRef surfaceBuffer;

}

@property (nonatomic, readonly) unsigned short *pixels;

@end

/** 

 *  @file SurfaceView.m

 *  Implementation of SurfaceView

 */

 

#import "SurfaceView.h"

@implementation SurfaceView

- (id)initWithFrame:(CGRect)frame {

    frame.origin.x /= 2;

    frame.origin.y /= 2;

    

    if (self = [super initWithFrame:frame]) {

        // Create Surface

        int w = frame.size.width, h = frame.size.height;

        surfaceBuffer = CoreSurfaceBufferCreate((CFDictionaryRef)[NSDictionary dictionaryWithObjectsAndKeys:

            [NSNumber numberWithInt:w],         kCoreSurfaceBufferWidth,

            [NSNumber numberWithInt:h],         kCoreSurfaceBufferHeight,

            [NSNumber numberWithInt:'L565'],    kCoreSurfaceBufferPixelFormat,

            [NSNumber numberWithInt:2*w*h],     kCoreSurfaceBufferAllocSize,

            [NSNumber numberWithBool:YES],      kCoreSurfaceBufferGlobal,

            [NSNumber numberWithInt:2*w],       kCoreSurfaceBufferPitch,

            @"PurpleGFXMem",                    kCoreSurfaceBufferMemoryRegion,

            nil]);

        

        // Create layer for surface

        CGRect frame2 = CGRectMake(frame.origin.x, frame.origin.y, 

                                   frame.size.width+1, frame.size.height+1);

        CoreSurfaceBufferLock(surfaceBuffer, 3);

        surfaceLayer = [[CALayer layer] retain];

        [surfaceLayer setMagnificationFilter:0];

        [surfaceLayer setEdgeAntialiasingMask:0];

        [surfaceLayer setFrame:frame2];

        [surfaceLayer setContents:surfaceBuffer];

        [surfaceLayer setOpaque:YES];

        [[self _layer] addSublayer:surfaceLayer];

        CoreSurfaceBufferUnlock(surfaceBuffer);

        

        // Get base address

        pixels = CoreSurfaceBufferGetBaseAddress(surfaceBuffer);

    }

    return self;

}

- (void)dealloc {

    [surfaceLayer release];

    [super dealloc];

}

- (void)drawRect:(CGRect)rect {

    // It will break if you remove this empty function

}

- (unsigned short*)pixels {

    return pixels;

}

@end