/*

     File: SampleCIView.m

 Abstract: Simple OpenGL based CoreImage view

  Version: 2.1

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 */

#import "SampleCIView.h"

#import <OpenGL/OpenGL.h>

#import <OpenGL/gl.h>

@interface SampleCIView (internalCalls)

- (BOOL)displaysWhenScreenProfileChanges;

- (void)viewWillMoveToWindow:(NSWindow*)newWindow;

- (void)displayProfileChanged:(NSNotification*)notification;

@end

@implementation SampleCIView

+ (NSOpenGLPixelFormat *)defaultPixelFormat

{

    static NSOpenGLPixelFormat *pf;

    if (pf == nil)

    {

        /* Making sure the context's pixel format doesn't have a recovery

         * renderer is important - otherwise CoreImage may not be able to

         * create deeper context's that share textures with this one. */

        static const NSOpenGLPixelFormatAttribute attr[] = {

            NSOpenGLPFAAccelerated,

            NSOpenGLPFANoRecovery,

            NSOpenGLPFAColorSize, 32,

#if MAC_OS_X_VERSION_MAX_ALLOWED >= MAC_OS_X_VERSION_10_5

            NSOpenGLPFAAllowOfflineRenderers,  /* allow use of offline renderers               */

#endif

            0

        };

        pf = [[NSOpenGLPixelFormat alloc] initWithAttributes:(void *)&attr];

    }

    return pf;

}

- (void)dealloc

{

    [[NSNotificationCenter defaultCenter] removeObserver:self];

    [_image release];

    [_contextOptions release];

    [_context release];

    [super dealloc];

}

- (void)setContextOptions:(NSMutableDictionary *)dict

{

    [_contextOptions release];

    _contextOptions = [dict retain];

    [_context release];

    _context = nil;

}

- (CIImage *)image

{

    return [[_image retain] autorelease];

}

- (void)setImage:(CIImage *)image dirtyRect:(CGRect)r

{

    if (_image != image)

    {

        [_image release];

        _image = [image retain];

        if (CGRectIsInfinite (r))

            [self setNeedsDisplay:YES];

        else

            [self setNeedsDisplayInRect:*(NSRect *)&r];

    }

}

- (void)setImage:(CIImage *)image

{

    [self setImage:image dirtyRect:CGRectInfinite];

}

- (void)prepareOpenGL

{

    GLint parm = 1;

    /* Enable beam-synced updates. */

    [[self openGLContext] setValues:&parm forParameter:NSOpenGLCPSwapInterval];

    /* Make sure that everything we don't need is disabled. Some of these

     * are enabled by default and can slow down rendering. */

    glDisable (GL_ALPHA_TEST);

    glDisable (GL_DEPTH_TEST);

    glDisable (GL_SCISSOR_TEST);

    glDisable (GL_BLEND);

    glDisable (GL_DITHER);

    glDisable (GL_CULL_FACE);

    glColorMask (GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);

    glDepthMask (GL_FALSE);

    glStencilMask (0);

    glClearColor (0.0f, 0.0f, 0.0f, 0.0f);

    glHint (GL_TRANSFORM_HINT_APPLE, GL_FASTEST);

}

- (void)viewBoundsDidChange:(NSRect)bounds

{

    /* For subclasses. */

}

- (void)updateMatrices

{

    NSRect r = [self bounds];

    if (!NSEqualRects (r, _lastBounds))

    {

        [[self openGLContext] update];

        /* Install an orthographic projection matrix (no perspective)

         * with the origin in the bottom left and one unit equal to one

         * device pixel. */

        glViewport (0, 0, r.size.width, r.size.height);

        glMatrixMode (GL_PROJECTION);

        glLoadIdentity ();

        glOrtho (0, r.size.width, 0, r.size.height, -1, 1);

        glMatrixMode (GL_MODELVIEW);

        glLoadIdentity ();

        _lastBounds = r;

        [self viewBoundsDidChange:r];

    }

}

- (BOOL)displaysWhenScreenProfileChanges

{

    return YES;

}

- (void)viewWillMoveToWindow:(NSWindow*)newWindow

{

    NSNotificationCenter* center = [NSNotificationCenter defaultCenter];

    [center removeObserver:self name:NSWindowDidChangeScreenProfileNotification object:nil];

    [center addObserver:self selector:@selector(displayProfileChanged:) name:NSWindowDidChangeScreenProfileNotification object:newWindow];

    [center addObserver:self selector:@selector(displayProfileChanged:) name:NSWindowDidMoveNotification object:newWindow];

    // When using OpenGL, we should disable the window's "one-shot" feature

    [newWindow setOneShot:NO];

}

- (void)displayProfileChanged:(NSNotification*)notification

{

    CGDirectDisplayID oldDid = _did;

    _did = (CGDirectDisplayID)[[[[[self window] screen] deviceDescription] objectForKey:@"NSScreenNumber"] pointerValue];

    if(_did == oldDid)

        return;

    _cglContext = [[self openGLContext] CGLContextObj];

    if(_pf == nil)

    {

        _pf = [self pixelFormat];

        if (_pf == nil)

            _pf = [[self class] defaultPixelFormat];

    }

    CGLLockContext(_cglContext);

    {

        // Create a new CIContext using the new output color space      

        [_context release];

#if MAC_OS_X_VERSION_MAX_ALLOWED <= MAC_OS_X_VERSION_10_5

        CMProfileRef displayProfile = NULL;

        CGColorSpaceRef displayColorSpace = NULL;

        // Ask ColorSync for our current display's profile

        CMGetProfileByAVID((CMDisplayIDType)_did, &displayProfile);

        displayColorSpace = CGColorSpaceCreateWithPlatformColorSpace(displayProfile);

        CMCloseProfile(displayProfile);

        if(_contextOptions)

        {

            [_contextOptions setObject:(id)displayColorSpace forKey:kCIContextOutputColorSpace];

        } else {

            _contextOptions = [[NSMutableDictionary dictionaryWithObject:(id)displayColorSpace forKey:kCIContextOutputColorSpace] retain];

        }

        [_contextOptions setObject:[[NSUserDefaults standardUserDefaults] objectForKey:@"useSoftwareRenderer"] forKey:kCIContextUseSoftwareRenderer];

        _context = [[CIContext contextWithCGLContext:_cglContext pixelFormat:[_pf CGLPixelFormatObj] options:_contextOptions] retain];

        CGColorSpaceRelease(displayColorSpace);

#else       

        if(_contextOptions)

        {

            [_contextOptions setObject:[[NSUserDefaults standardUserDefaults] objectForKey:@"useSoftwareRenderer"] forKey:kCIContextUseSoftwareRenderer];

        } else {

            _contextOptions = [[NSMutableDictionary dictionaryWithObject:[[NSUserDefaults standardUserDefaults] objectForKey:@"useSoftwareRenderer"] forKey:kCIContextUseSoftwareRenderer] retain];

        }

        // For 10.6 onwards we use the new API but do not pass in a colorspace as. 

        // Since the cgl context will be rendered to the display, it is valid to rely on CI to get the colorspace from the context.

        _context = [[CIContext contextWithCGLContext:_cglContext pixelFormat:[_pf CGLPixelFormatObj] colorSpace:nil options:_contextOptions] retain];    

#endif

    }

    CGLUnlockContext(_cglContext);

}

- (void)drawRect:(NSRect)r

{

    CGRect ir, rr;

    CGImageRef cgImage;

    [[self openGLContext] makeCurrentContext];

    /* Allocate a CoreImage rendering context using the view's OpenGL

     * context as its destination if none already exists. */

    if (_context == nil)

        [self displayProfileChanged:nil];

    ir = CGRectIntegral (*(CGRect *)&r);

    if ([NSGraphicsContext currentContextDrawingToScreen])

    {

        [self updateMatrices];

        /* Clear the specified subrect of the OpenGL surface then

         * render the image into the view. Use the GL scissor test to

         * clip to * the subrect. Ask CoreImage to generate an extra

         * pixel in case * it has to interpolate (allow for hardware

         * inaccuracies) */

        rr = CGRectIntersection (CGRectInset (ir, -1.0f, -1.0f),

                                 *(CGRect *)&_lastBounds);

        glScissor (ir.origin.x, ir.origin.y, ir.size.width, ir.size.height);

        glEnable (GL_SCISSOR_TEST);

        glClear (GL_COLOR_BUFFER_BIT);

        if ([self respondsToSelector:@selector (drawRect:inCIContext:)])  // for subclasses to provide their own drawing method

        {

            [self drawRect:*(NSRect *)&rr inCIContext:_context];

        }

        else if (_image != nil)

        {

            [_context drawImage:_image inRect:rr fromRect:rr];

        }

        glDisable (GL_SCISSOR_TEST);

        /* Flush the OpenGL command stream. If the view is double

         * buffered this should be replaced by [[self openGLContext]

         * flushBuffer]. */

        glFlush ();

    }

    else

    {

        /* Printing the view contents. Render using CG, not OpenGL. */

        if ([self respondsToSelector:@selector (drawRect:inCIContext:)])

        {

            [self drawRect:*(NSRect *)&ir inCIContext:_context];

        }

        else if (_image != nil)

        {

            cgImage = [_context createCGImage:_image fromRect:ir format:kCIFormatRGBA16 colorSpace:nil];

            if (cgImage != NULL)

            {

                CGContextDrawImage ([[NSGraphicsContext currentContext]

                                     graphicsPort], ir, cgImage);

                CGImageRelease (cgImage);

            }

        }

    }

}

@end