#import "GPUImageScreenBlendFilter.h"
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#if TARGET_IPHONE_SIMULATOR || TARGET_OS_IPHONE
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NSString *const kGPUImageScreenBlendFragmentShaderString = SHADER_STRING
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(
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varying highp vec2 textureCoordinate;
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varying highp vec2 textureCoordinate2;
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uniform sampler2D inputImageTexture;
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uniform sampler2D inputImageTexture2;
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void main()
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{
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mediump vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);
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mediump vec4 textureColor2 = texture2D(inputImageTexture2, textureCoordinate2);
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mediump vec4 whiteColor = vec4(1.0);
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gl_FragColor = whiteColor - ((whiteColor - textureColor2) * (whiteColor - textureColor));
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}
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);
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#else
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NSString *const kGPUImageScreenBlendFragmentShaderString = SHADER_STRING
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(
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varying vec2 textureCoordinate;
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varying vec2 textureCoordinate2;
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uniform sampler2D inputImageTexture;
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uniform sampler2D inputImageTexture2;
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void main()
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{
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vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);
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vec4 textureColor2 = texture2D(inputImageTexture2, textureCoordinate2);
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vec4 whiteColor = vec4(1.0);
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gl_FragColor = whiteColor - ((whiteColor - textureColor2) * (whiteColor - textureColor));
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}
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);
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#endif
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@implementation GPUImageScreenBlendFilter
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- (id)init;
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{
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if (!(self = [super initWithFragmentShaderFromString:kGPUImageScreenBlendFragmentShaderString]))
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{
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return nil;
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}
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return self;
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}
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@end
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