#import "GPUImageExposureFilter.h"
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#if TARGET_IPHONE_SIMULATOR || TARGET_OS_IPHONE
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NSString *const kGPUImageExposureFragmentShaderString = SHADER_STRING
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(
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varying highp vec2 textureCoordinate;
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uniform sampler2D inputImageTexture;
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uniform highp float exposure;
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void main()
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{
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highp vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);
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gl_FragColor = vec4(textureColor.rgb * pow(2.0, exposure), textureColor.w);
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}
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);
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#else
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NSString *const kGPUImageExposureFragmentShaderString = SHADER_STRING
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(
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varying vec2 textureCoordinate;
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uniform sampler2D inputImageTexture;
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uniform float exposure;
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void main()
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{
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vec4 textureColor = texture2D(inputImageTexture, textureCoordinate);
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gl_FragColor = vec4(textureColor.rgb * pow(2.0, exposure), textureColor.w);
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}
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);
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#endif
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@implementation GPUImageExposureFilter
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@synthesize exposure = _exposure;
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#pragma mark -
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#pragma mark Initialization and teardown
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- (id)init;
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{
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if (!(self = [super initWithFragmentShaderFromString:kGPUImageExposureFragmentShaderString]))
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{
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return nil;
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}
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exposureUniform = [filterProgram uniformIndex:@"exposure"];
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self.exposure = 0.0;
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return self;
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}
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#pragma mark -
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#pragma mark Accessors
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- (void)setExposure:(CGFloat)newValue;
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{
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_exposure = newValue;
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[self setFloat:_exposure forUniform:exposureUniform program:filterProgram];
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}
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@end
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