EffectStack.m

/*
     File: EffectStack.m
 Abstract: n/a
  Version: 2.1
 
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#import "EffectStack.h"
#import "CoreImageView.h"
 
@implementation EffectStack
 
- (id)init
{
    self = [super init];
    if (self)
    {
        layers = [[NSMutableArray alloc] init];
    }
    return self;
}
 
- (void)dealloc
{
    [baseImage release];
    [layers release];
    [super dealloc];
}
 
// insert a filter layer into the layers array
- (void)insertFilterLayer:(CIFilter *)filter atIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    d = [NSMutableDictionary dictionaryWithCapacity:2];
    [d setValue:@"filter" forKey:@"type"];
    [d setValue:filter forKey:@"filter"];
    [d setValue:[NSNumber numberWithBool:YES] forKey:@"enabled"];
    [layers insertObject:d atIndex:index];
}
 
// insert an image layer into the layers array
- (void)insertImageLayer:(CIImage *)image withFilename:(NSString *)filename atIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    d = [NSMutableDictionary dictionaryWithCapacity:2];
    [d setValue:@"image" forKey:@"type"];
    [d setValue:image forKey:@"image"];
    [d setValue:[NSNumber numberWithDouble:0.0] forKey:@"offsetX"];
    [d setValue:[NSNumber numberWithDouble:0.0] forKey:@"offsetY"];
    [d setValue:[NSNumber numberWithBool:YES] forKey:@"enabled"];
    [d setValue:filename forKey:@"filename"];
    [layers insertObject:d atIndex:index];
}
 
// insert a text layer into the layers array
- (void)insertTextLayer:(NSString *)string withImage:(CIImage *)image atIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    d = [NSMutableDictionary dictionaryWithCapacity:2];
    [d setValue:@"text" forKey:@"type"];
    [d setValue:image forKey:@"image"];
    [d setValue:string forKey:@"string"];
    [d setValue:[NSNumber numberWithDouble:1.0] forKey:@"scale"];
    [d setValue:[NSNumber numberWithDouble:0.0] forKey:@"offsetX"];
    [d setValue:[NSNumber numberWithDouble:0.0] forKey:@"offsetY"];
    [d setValue:[NSNumber numberWithBool:YES] forKey:@"enabled"];
    [layers insertObject:d atIndex:index];
}
 
// remove an element from the layers array
- (void)removeLayerAtIndex:(NSInteger)index
{
    [layers removeObjectAtIndex:index];
}
 
// remove all elements from the layers array
- (void)removeAllLayers
{
    [layers removeAllObjects];
}
 
// return the number of elements in the layers array
- (NSInteger)layerCount
{
    return [layers count];
}
 
// getter: layers[index].enabled
- (BOOL)layerEnabled:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return NO;
    }
    d = [layers objectAtIndex:index];
    return [[d valueForKey:@"enabled"] boolValue];
}
 
// getter: layers[index].type
- (NSString *)typeAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    return [d valueForKey:@"type"];
}
 
// getter: layers[index].filter
- (CIFilter *)filterAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"filter"])
        return nil;
    return [d valueForKey:@"filter"];
}
 
// getter: layers[index].image
- (CIImage *)imageAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"image"] && ![[d valueForKey:@"type"] isEqualToString:@"text"])
        return nil;
    return [d valueForKey:@"image"];
}
 
// getter: layers[index].offset
- (NSPoint)offsetAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return NSMakePoint(0.0, 0.0);
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"image"] && ![[d valueForKey:@"type"] isEqualToString:@"text"])
        return NSMakePoint(0.0, 0.0);
    return NSMakePoint([[d valueForKey:@"offsetX"] doubleValue], [[d valueForKey:@"offsetY"] doubleValue]);
}
 
// getter: layers[index].filename
- (NSString *)filenameAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"image"])
        return nil;
    return [d valueForKey:@"filename"];
}
 
// getter: layers[index].imageFilePath
- (NSString *)imageFilePathAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"image"])
        return nil;
    return [d valueForKey:@"imageFilePath"];
}
 
// getter: layers[index].imageFileData
- (NSData *)imageFileDataAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"image"])
        return nil;
    return [d valueForKey:@"imageFileData"];
}
 
// getter: layers[index].string
- (NSString *)stringAtIndex:(NSInteger)index
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"text"])
        return nil;
    return [d valueForKey:@"string"];
}
 
// getter: layers[index] - used for text case where there are way too many to access otherwise
- (NSMutableDictionary *)mutableDictionaryAtIndex:(NSInteger)index
{
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    return [layers objectAtIndex:index];
}
 
// getter: layers[0].image
- (CIImage *)baseImage
{
    if ([[self typeAtIndex:0] isEqualToString:@"image"])
        return [self imageAtIndex:0];
    return nil;
}
 
// getter: [layers[0].imageFilePaths valueForKey:key].path
- (NSString *)filterLayer:(NSInteger)index imageFilePathValueForKey:(NSString *)key
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"filter"])
        return nil;
    d = [d valueForKey:@"imageFilePaths"];
    if (d == nil)
        return nil;
    return [[d valueForKey:key] valueForKey:@"path"];
}
 
// getter: [layers[0].imageFilePaths valueForKey:key].data
- (NSData *)filterLayer:(NSInteger)index imageFileDataValueForKey:(NSString *)key
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return nil;
    }
    d = [layers objectAtIndex:index];
    if (![[d valueForKey:@"type"] isEqualToString:@"filter"])
        return nil;
    d = [d valueForKey:@"imageFilePaths"];
    if (d == nil)
        return nil;
    return [[d valueForKey:key] valueForKey:@"data"];
}
 
// setter: [layers[index].imageFilePaths setValue:path forKey:key]
- (void)setFilterLayer:(NSInteger)index imageFilePathValue:(NSString *)path forKey:(NSString *)key
{
    NSMutableDictionary *d, *d2, *d3;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return;
    }
    d = [layers objectAtIndex:index];
    if ([[d valueForKey:@"type"] isEqualToString:@"filter"])
    {
        d2 = [d valueForKey:@"imageFilePaths"];
        if (d2 == nil)
        {
            d2 = [NSMutableDictionary dictionary];
            [d setValue:d2 forKey:@"imageFilePaths"];
        }
        d3 = [NSMutableDictionary dictionary];
        [d3 setValue:path forKey:@"path"];
        // keep image file data around too!
        [d3 setValue:[NSData dataWithContentsOfMappedFile:path] forKey:@"data"];
        [d2 setValue:d3 forKey:key];
    }
}
 
// setter: layers[index].enabled
- (void)setLayer:(NSInteger)index enabled:(BOOL)enabled
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return;
    }
    d = [layers objectAtIndex:index];
    [d setValue:[NSNumber numberWithBool:enabled] forKey:@"enabled"];
}
 
// setter: layers[index].offset
- (void)setImageLayer:(NSInteger)index offset:(NSPoint)offset
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return;
    }
    d = [layers objectAtIndex:index];
    if ([[d valueForKey:@"type"] isEqualToString:@"image"])
    {
        [d setValue:[NSNumber numberWithDouble:offset.x] forKey:@"offsetX"];
        [d setValue:[NSNumber numberWithDouble:offset.y] forKey:@"offsetY"];
    }
}
 
// setter: layers[index].imageFilePath
- (void)setImageLayer:(NSInteger)index imageFilePath:(NSString *)path
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return;
    }
    d = [layers objectAtIndex:index];
    if ([[d valueForKey:@"type"] isEqualToString:@"image"])
    {
        [d setValue:path forKey:@"imageFilePath"];
        // keep image file data around too!
        [d setValue:[NSData dataWithContentsOfMappedFile:path] forKey:@"imageFileData"];
    }
}
 
// setter: layers[index].offset
- (void)setTextLayer:(NSInteger)index offset:(NSPoint)offset
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return;
    }
    d = [layers objectAtIndex:index];
    if ([[d valueForKey:@"type"] isEqualToString:@"text"])
    {
        [d setValue:[NSNumber numberWithDouble:offset.x] forKey:@"offsetX"];
        [d setValue:[NSNumber numberWithDouble:offset.y] forKey:@"offsetY"];
    }
}
 
// setter: layers[index].image/filename
- (void)setImageLayer:(NSInteger)index image:(CIImage *)image andFilename:(NSString *)filename
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return;
    }
    d = [layers objectAtIndex:index];
    if ([[d valueForKey:@"type"] isEqualToString:@"image"])
    {
        [d setValue:image forKey:@"image"];
        [d setValue:filename forKey:@"filename"];
    }
}
 
// setter: layers[index].string/image
- (void)setTextLayer:(NSInteger)index string:(NSString *)string andImage:(CIImage *)image
{
    NSMutableDictionary *d;
    
    if (index < 0 || index >= [self layerCount])
    {
        printf("index %d is out of range (%d layers in model)\n", (int)index, (int)[self layerCount]);
        return;
    }
    d = [layers objectAtIndex:index];
    if ([[d valueForKey:@"type"] isEqualToString:@"text"])
    {
        [d setValue:image forKey:@"image"];
        [d setValue:string forKey:@"string"];
    }
}
 
// setter: layers[0].image/filename and image/path
- (void)setBaseImage:(CIImage *)image withFilename:(NSString *)filename andImageFilePath:(NSString *)path
{
    NSMutableDictionary *d;
    
    if ([self layerCount] > 0 && [[self typeAtIndex:0] isEqualToString:@"image"])
    {
        d = [layers objectAtIndex:0];
        [d setValue:image forKey:@"image"];
        [d setValue:filename forKey:@"filename"];
        [d setValue:path forKey:@"imageFilePath"];
    }
    else if ([self layerCount] == 0)
    {
        [self insertImageLayer:image withFilename:filename atIndex:0];
        d = [layers objectAtIndex:0];
        [d setValue:path forKey:@"imageFilePath"];
        // keep image file data around too!
        [d setValue:[NSData dataWithContentsOfMappedFile:path] forKey:@"imageFileData"];
    }
    else
        printf("attempted setBaseImage with non-empty effect stack\n");
}
 
// return the core image graph for the effect stack (constrained to the rectangle)
- (CIImage *)coreImageResultForRect:(NSRect)bounds
{
    BOOL usesExtent, usesImage, hasBackground;
    NSInteger i, count;
    CIFilter *f;
    CIImage  *result;
    NSDictionary *attr;
    NSArray *inputKeys;
    NSString *key, *classstring, *type;
    NSEnumerator *enumerator;
    NSMutableArray *resultstack;
    
    resultstack = [NSMutableArray arrayWithCapacity:10];
    // get result of filter running over image
    count = [self layerCount];
    result = nil;
    for (i = 0; i < count; i++)
    {
        if (![self layerEnabled:i])
            continue;
        type = [self typeAtIndex:i];
        if ([type isEqualToString:@"filter"])
        {
            // filter layer
            f = [self filterAtIndex:i];
            if (f == nil)
                continue;
            usesExtent = NO;
            usesImage = NO;
            hasBackground = NO;
            attr = [f attributes];
            inputKeys = [f inputKeys];
            // scan the input parameters for various cases we need to handle
            enumerator = [inputKeys objectEnumerator];
            while ((key = [enumerator nextObject]) != nil) 
            {
                id parameter = [attr objectForKey:key];
                if ([parameter isKindOfClass:[NSDictionary class]])
                {
                    classstring = [(NSDictionary *)parameter objectForKey: kCIAttributeClass];
                    if ([classstring isEqualToString:@"CIVector"] && [key isEqualToString:@"inputExtent"])
                        usesExtent = YES;
                    if ([key isEqualToString:@"inputImage"])
                        usesImage = YES;
                    if ([key isEqualToString:@"inputBackgroundImage"])
                        hasBackground = YES;
                }
            }
            // stack generators here
            if (!usesImage && result != nil)
                // check for automatic SOver of layered results
                [resultstack addObject:result]; // keep result around for SOver at end
            // supply chained image parameters here
            if (usesImage)
            {
                if (result != nil)
                    {
                    if (hasBackground)
                        [f setValue:result forKey:@"inputBackgroundImage"]; // chain layers (blend modes by background)
                    else
                        [f setValue:result forKey:@"inputImage"]; // chain layers
                    }
            }
            // supply the obvious extent for any extent parameters
            if (usesExtent)
                [f setValue: [CIVector vectorWithX: 0  Y: 0  Z: NSWidth(bounds)  W: NSHeight(bounds)]
                  forKey: @"inputExtent"];
            // get the filter result
            result = [f valueForKey: @"outputImage"];
        }
        else if ([type isEqualToString:@"image"] || [type isEqualToString:@"text"])
        {
            // image or text layer
            if (result != nil)
                // check for automatic SOver of layered results
                [resultstack addObject:result]; // keep result around for SOver at end
            // get the image and offset
            CIImage *im = [self imageAtIndex:i];
            NSPoint offset = [self offsetAtIndex:i];
            // apply an affine transform to the iamge to account for the offset
            f = [CIFilter filterWithName:@"CIAffineTransform"];
            NSAffineTransform *t = [NSAffineTransform transform];
            [t translateXBy:offset.x yBy:offset.y];
            [f setValue:t forKey:@"inputTransform"];
            [f setValue:im forKey:@"inputImage"];
            // and get the result
            result = [f valueForKey:@"outputImage"];
        }
    }
    // at the end, if there are results stacked (base image, other image layers, text layers, generators), overlay them using SOver
    if ([resultstack count] > 0)
    {
        CIFilter *sover;
        CIImage *background = nil;
        
        count = [resultstack count];
        for (i = 0; i < count; i++)
        {
            if (i == 0)
                background = [resultstack objectAtIndex:i];
            else
            {
                sover = [CIFilter filterWithName:@"CISourceOverCompositing" keysAndValues:
                  @"inputBackgroundImage", background, @"inputImage", [resultstack objectAtIndex:i], nil];
                background = [sover valueForKey:@"outputImage"];
            }
        }
        if (result == nil)
            result = background;
        else
        {
            // finally composite result over stacked items
            sover = [CIFilter filterWithName:@"CISourceOverCompositing" keysAndValues:
              @"inputBackgroundImage", background, @"inputImage", result, nil];
            result = [sover valueForKey:@"outputImage"];
        }
    }
    return result;
}
 
// decide if a filter in the effect stack has a missing image parameter
// ignore the chained image parameter (either inputImage or inputBackgroundImage for blend modes/Porter-Duff modes)
- (BOOL)filterHasMissingImage:(CIFilter *)f
{
    BOOL hasBackground, missingImage;
    NSString *key, *classstring;
    NSDictionary *parameter, *attr;
    NSArray *inputKeys;
    NSEnumerator *enumerator;
    
    // first check the filter for an uninitialized image
    attr = [f attributes];
    inputKeys = [f inputKeys];
    hasBackground = NO;
    enumerator = [inputKeys objectEnumerator];
    // decide first if the filter has a background image - it is a blend mode or compositing method
    while ((key = [enumerator nextObject]) != nil) 
    {
        parameter = [attr objectForKey:key];
        classstring = [parameter objectForKey: kCIAttributeClass];
        if ([classstring isEqualToString:@"CIImage"] && [key isEqualToString:@"inputBackgroundImage"])
            hasBackground = YES;
    }
    missingImage = NO;
    enumerator = [inputKeys objectEnumerator];
    while ((key = [enumerator nextObject]) != nil) 
    {
        parameter = [attr objectForKey:key];
        classstring = [parameter objectForKey: kCIAttributeClass];
        if ([classstring isEqualToString:@"CIImage"])
        {
            if (hasBackground)
            {
                if (![key isEqualToString:@"inputBackgroundImage"] && [f valueForKey:key] == nil)
                {
                    missingImage = YES;
                    break;
                }
            }
            else
            {
                if (![key isEqualToString:@"inputImage"] && [f valueForKey:key] == nil)
                {
                    missingImage = YES;
                    break;
                }
            }
        }
    }
    return missingImage;
}
 
// determine if the entire effect stack has a missing image - if yes, then the effect stack can't be evaluated
- (BOOL)hasMissingImage
{
    NSInteger i, count;
    CIFilter *f;
    
    count = [self layerCount];
    for (i = 0; i < count; i++)
    {
        f = [self filterAtIndex:i];
        if (f != nil && [self filterHasMissingImage:f])
            return YES;
    }
    return NO;
}
 
// encode arbitrary parameter objects for filters into XML-compatible NSNumber's
- (void)encodeValue:(id)obj forKey:(NSString *)key intoDictionary:(NSMutableDictionary *)v
    {
    NSAffineTransformStruct S;
    
    // decide what it is and store values in the values dictionary
    if ([obj isKindOfClass:[NSNumber class]])
        [v setValue:obj forKey:key];
    else if ([obj isKindOfClass:[CIVector class]])
        {
        [v setValue:[obj stringRepresentation] forKey:[key stringByAppendingString:@"_CIVectorValue"]];
        }
    else if ([obj isKindOfClass:[CIColor class]])
        {
        [v setValue:[obj stringRepresentation] forKey:[key stringByAppendingString:@"_CIColorValue"]];
        }
    else if ([obj isKindOfClass:[NSAffineTransform class]])
        {
        S = [obj transformStruct];
        [v setValue:[NSNumber numberWithDouble:S.m11] forKey:[key stringByAppendingString:@"_m11"]];
        [v setValue:[NSNumber numberWithDouble:S.m12] forKey:[key stringByAppendingString:@"_m12"]];
        [v setValue:[NSNumber numberWithDouble:S.m21] forKey:[key stringByAppendingString:@"_m21"]];
        [v setValue:[NSNumber numberWithDouble:S.m22] forKey:[key stringByAppendingString:@"_m22"]];
        [v setValue:[NSNumber numberWithDouble:S.tX] forKey:[key stringByAppendingString:@"_tX"]];
        [v setValue:[NSNumber numberWithDouble:S.tY] forKey:[key stringByAppendingString:@"_tY"]];
        }
    }
 
// decode XML-compatible NSNumber's into arbitrary parameter objects for filters
- (id)decodedValueForKey:(NSString *)key ofClass:(NSString *)classname fromDictionary:(NSDictionary *)v
    {
    if ([classname isEqualToString:@"NSNumber"])
        return [v valueForKey:key];
    else if ([classname isEqualToString:@"CIVector"])
    {
        NSString    *objValue = (NSString*)[v valueForKey:[key stringByAppendingString:@"_CIVectorValue"]];
        
        if (objValue == nil)
            return nil;
        return [CIVector vectorWithString:objValue];
    }
    else if ([classname isEqualToString:@"CIColor"])
    {
        NSString    *objValue = (NSString*)[v valueForKey:[key stringByAppendingString:@"_CIColorValue"]];
        
        if (objValue == nil)
            return nil;
        return [CIColor colorWithString:objValue];
    }
    else if ([classname isEqualToString:@"NSAffineTransform"])
    {
        NSAffineTransformStruct S;
        NSAffineTransform *t;
        
        if ([v valueForKey:[key stringByAppendingString:@"_m11"]] == nil)
            return nil;
        S.m11 = [[v valueForKey:[key stringByAppendingString:@"_m11"]] doubleValue];
        S.m12 = [[v valueForKey:[key stringByAppendingString:@"_m12"]] doubleValue];
        S.m21 = [[v valueForKey:[key stringByAppendingString:@"_m21"]] doubleValue];
        S.m22 = [[v valueForKey:[key stringByAppendingString:@"_m22"]] doubleValue];
        S.tX = [[v valueForKey:[key stringByAppendingString:@"_tX"]] doubleValue];
        S.tY = [[v valueForKey:[key stringByAppendingString:@"_tY"]] doubleValue];
        t = [[[NSAffineTransform alloc] init] autorelease];
        [t setTransformStruct:S];
        return t;
    }
    else if ([classname isEqualToString:@"CIImage"])
    {
        if ([v valueForKey:key] == nil)
            return nil;
    }
    return nil;
    }
 
@end


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