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  "title" : "Core Text Constants"
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# Core Text Constants

## Topics

### Constants

[`var ATSFONTREF_DEFINED: Int32`](/documentation/CoreText/ATSFONTREF_DEFINED)

[`var kBSLNIdeographicHighBaseline: Int`](/documentation/CoreText/kBSLNIdeographicHighBaseline)

[`let kCTAdaptiveImageProviderAttributeName: CFString`](/documentation/CoreText/kCTAdaptiveImageProviderAttributeName)

[`let kCTBackgroundColorAttributeName: CFString`](/documentation/CoreText/kCTBackgroundColorAttributeName)

[`let kCTBaselineClassAttributeName: CFString`](/documentation/CoreText/kCTBaselineClassAttributeName)

[`let kCTBaselineClassHanging: CFString`](/documentation/CoreText/kCTBaselineClassHanging)

[`let kCTBaselineClassIdeographicCentered: CFString`](/documentation/CoreText/kCTBaselineClassIdeographicCentered)

[`let kCTBaselineClassIdeographicHigh: CFString`](/documentation/CoreText/kCTBaselineClassIdeographicHigh)

[`let kCTBaselineClassIdeographicLow: CFString`](/documentation/CoreText/kCTBaselineClassIdeographicLow)

[`let kCTBaselineClassMath: CFString`](/documentation/CoreText/kCTBaselineClassMath)

[`let kCTBaselineClassRoman: CFString`](/documentation/CoreText/kCTBaselineClassRoman)

[`let kCTBaselineInfoAttributeName: CFString`](/documentation/CoreText/kCTBaselineInfoAttributeName)

[`let kCTBaselineOriginalFont: CFString`](/documentation/CoreText/kCTBaselineOriginalFont)

[`let kCTBaselineReferenceFont: CFString`](/documentation/CoreText/kCTBaselineReferenceFont)

[`let kCTBaselineReferenceInfoAttributeName: CFString`](/documentation/CoreText/kCTBaselineReferenceInfoAttributeName)

[`let kCTFontCollectionDisallowAutoActivationOption: CFString`](/documentation/CoreText/kCTFontCollectionDisallowAutoActivationOption)

[`let kCTFontCollectionIncludeDisabledFontsOption: CFString`](/documentation/CoreText/kCTFontCollectionIncludeDisabledFontsOption)

[`let kCTFontDescriptorMatchingCurrentAssetSize: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingCurrentAssetSize)

[`let kCTFontDescriptorMatchingDescriptors: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingDescriptors)

[`let kCTFontDescriptorMatchingError: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingError)

[`let kCTFontDescriptorMatchingPercentage: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingPercentage)

[`let kCTFontDescriptorMatchingResult: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingResult)

[`let kCTFontDescriptorMatchingSourceDescriptor: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingSourceDescriptor)

[`let kCTFontDescriptorMatchingTotalAssetSize: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingTotalAssetSize)

[`let kCTFontDescriptorMatchingTotalDownloadedSize: CFString`](/documentation/CoreText/kCTFontDescriptorMatchingTotalDownloadedSize)

[`let kCTFontDownloadableAttribute: CFString`](/documentation/CoreText/kCTFontDownloadableAttribute)

The font downloadable state.

[`let kCTFontDownloadedAttribute: CFString`](/documentation/CoreText/kCTFontDownloadedAttribute)

The download state.

[`let kCTFontManagerBundleIdentifier: CFString`](/documentation/CoreText/kCTFontManagerBundleIdentifier)

[`let kCTFontManagerErrorDomain: CFString`](/documentation/CoreText/kCTFontManagerErrorDomain)

[`let kCTFontManagerErrorFontAssetNameKey: CFString`](/documentation/CoreText/kCTFontManagerErrorFontAssetNameKey)

[`let kCTFontManagerErrorFontDescriptorsKey: CFString`](/documentation/CoreText/kCTFontManagerErrorFontDescriptorsKey)

[`let kCTFontManagerErrorFontURLsKey: CFString`](/documentation/CoreText/kCTFontManagerErrorFontURLsKey)

[`let kCTFontManagerRegisteredFontsChangedNotification: CFString`](/documentation/CoreText/kCTFontManagerRegisteredFontsChangedNotification)

[`let kCTFontOpenTypeFeatureTag: CFString`](/documentation/CoreText/kCTFontOpenTypeFeatureTag)

[`let kCTFontOpenTypeFeatureValue: CFString`](/documentation/CoreText/kCTFontOpenTypeFeatureValue)

[`let kCTFontOpticalSizeAttribute: CFString`](/documentation/CoreText/kCTFontOpticalSizeAttribute)

[`let kCTFontRegistrationUserInfoAttribute: CFString`](/documentation/CoreText/kCTFontRegistrationUserInfoAttribute)

[`var kCTFontTableAnkr: Int`](/documentation/CoreText/kCTFontTableAnkr)

[`var kCTFontTableLtag: Int`](/documentation/CoreText/kCTFontTableLtag)

[`var kCTFontTableMATH: Int`](/documentation/CoreText/kCTFontTableMATH)

[`let kCTFontVariationAxesAttribute: CFString`](/documentation/CoreText/kCTFontVariationAxesAttribute)

[`let kCTHorizontalInVerticalFormsAttributeName: CFString`](/documentation/CoreText/kCTHorizontalInVerticalFormsAttributeName)

Setting text in tate-chu-yoko form (horizontal numerals in vertical text).

[`let kCTLanguageAttributeName: CFString`](/documentation/CoreText/kCTLanguageAttributeName)

The name of the text language.

[`let kCTRubyAnnotationAttributeName: CFString`](/documentation/CoreText/kCTRubyAnnotationAttributeName)

[`let kCTRubyAnnotationScaleToFitAttributeName: CFString`](/documentation/CoreText/kCTRubyAnnotationScaleToFitAttributeName)

[`let kCTRubyAnnotationSizeFactorAttributeName: CFString`](/documentation/CoreText/kCTRubyAnnotationSizeFactorAttributeName)

[`var kCTVersionNumber10_10: Int32`](/documentation/CoreText/kCTVersionNumber10_10)

[`var kCTVersionNumber10_11: Int32`](/documentation/CoreText/kCTVersionNumber10_11)

[`var kCTVersionNumber10_12: Int32`](/documentation/CoreText/kCTVersionNumber10_12)

[`var kCTVersionNumber10_13: Int32`](/documentation/CoreText/kCTVersionNumber10_13)

[`var kCTVersionNumber10_14: Int32`](/documentation/CoreText/kCTVersionNumber10_14)

[`var kCTVersionNumber10_15: Int32`](/documentation/CoreText/kCTVersionNumber10_15)

[`var kCTVersionNumber10_5_2: Int32`](/documentation/CoreText/kCTVersionNumber10_5_2)

[`var kCTVersionNumber10_5_3: Int32`](/documentation/CoreText/kCTVersionNumber10_5_3)

[`var kCTVersionNumber10_5_5: Int32`](/documentation/CoreText/kCTVersionNumber10_5_5)

[`var kCTVersionNumber10_5: Int32`](/documentation/CoreText/kCTVersionNumber10_5)

[`var kCTVersionNumber10_6: Int32`](/documentation/CoreText/kCTVersionNumber10_6)

[`var kCTVersionNumber10_7: Int32`](/documentation/CoreText/kCTVersionNumber10_7)

[`var kCTVersionNumber10_8: Int32`](/documentation/CoreText/kCTVersionNumber10_8)

[`var kCTVersionNumber10_9: Int32`](/documentation/CoreText/kCTVersionNumber10_9)

[`var kCTVersionNumber11_0: Int32`](/documentation/CoreText/kCTVersionNumber11_0)

[`let kCTWritingDirectionAttributeName: CFString`](/documentation/CoreText/kCTWritingDirectionAttributeName)

[`var kCTWritingDirectionEmbedding: Int`](/documentation/CoreText/kCTWritingDirectionEmbedding)

[`var kCTWritingDirectionOverride: Int`](/documentation/CoreText/kCTWritingDirectionOverride)

[`var kKERXDescending: Int`](/documentation/CoreText/kKERXDescending)

[`var kKERXValuesAreLong: Int`](/documentation/CoreText/kKERXValuesAreLong)

[`var kLanguageTagType: Int`](/documentation/CoreText/kLanguageTagType)

[`var kLTAGCurrentVersion: Int`](/documentation/CoreText/kLTAGCurrentVersion)

[`var kMORXCoverLogicalOrder: Int`](/documentation/CoreText/kMORXCoverLogicalOrder)

[`var kSTKCrossStreamReset: Int`](/documentation/CoreText/kSTKCrossStreamReset)


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