# Core Graphics Constants ## Topics ### Constants [`class let conversionBlackPointCompensation: CFString`](/documentation/CoreGraphics/CGColor/conversionBlackPointCompensation) An option for whether to apply black point compensation when converting between color profiles. [`var kCGDisplayBitsPerPixel: String`](/documentation/CoreGraphics/kCGDisplayBitsPerPixel) Specifies a CFNumber integer value that represents the number of bits in a pixel. [`var kCGDisplayBitsPerSample: String`](/documentation/CoreGraphics/kCGDisplayBitsPerSample) Specifies a CFNumber integer value that represents the number of bits in an individual sample (for example, a color value in an RGB pixel). [`var kCGDisplayBlendNormal: Double`](/documentation/CoreGraphics/kCGDisplayBlendNormal) The blend color is not applied at the start or end of a fade operation. [`var kCGDisplayBlendSolidColor: Double`](/documentation/CoreGraphics/kCGDisplayBlendSolidColor) The user sees only the blend color at the start or end of a fade operation. [`var kCGDisplayBytesPerRow: String`](/documentation/CoreGraphics/kCGDisplayBytesPerRow) Specifies a CFNumber integer value that represents the number of bytes in a row on the display. [`var kCGDisplayFadeReservationInvalidToken: Int32`](/documentation/CoreGraphics/kCGDisplayFadeReservationInvalidToken) [`var kCGDisplayHeight: String`](/documentation/CoreGraphics/kCGDisplayHeight) Specifies a CFNumber integer value that represents the height of the display in pixels. [`var kCGDisplayIOFlags: String`](/documentation/CoreGraphics/kCGDisplayIOFlags) Specifies a CFNumber integer value that contains the I/O Kit display mode flags. For more information, see the header file `IOKit/IOGraphicsTypes.h`. [`var kCGDisplayMode: String`](/documentation/CoreGraphics/kCGDisplayMode) Specifies a `CFNumber` integer value that represents the I/O Kit display mode number. [`var kCGDisplayModeIsInterlaced: String`](/documentation/CoreGraphics/kCGDisplayModeIsInterlaced) Specifies a CFBoolean value indicating that the I/O Kit interlace mode flag is set. [`var kCGDisplayModeIsSafeForHardware: String`](/documentation/CoreGraphics/kCGDisplayModeIsSafeForHardware) Specifies a CFBoolean value indicating that the display mode doesn’t need a confirmation dialog to be set. [`var kCGDisplayModeIsStretched: String`](/documentation/CoreGraphics/kCGDisplayModeIsStretched) Specifies a CFBoolean value indicating that the I/O Kit stretched mode flag is set. [`var kCGDisplayModeIsTelevisionOutput: String`](/documentation/CoreGraphics/kCGDisplayModeIsTelevisionOutput) Specifies a CFBoolean value indicating that the I/O Kit television output mode flag is set. [`var kCGDisplayModeUsableForDesktopGUI: String`](/documentation/CoreGraphics/kCGDisplayModeUsableForDesktopGUI) Specifies a CFBoolean value that indicates whether the display is suitable for use with the macOS graphical user interface. The criteria include factors such as sufficient width and height and adequate pixel depth. [`var kCGDisplayRefreshRate: String`](/documentation/CoreGraphics/kCGDisplayRefreshRate) Specifies a `CFNumber` double-precision floating point value that represents the refresh rate of a CRT display. [`var kCGDisplaySamplesPerPixel: String`](/documentation/CoreGraphics/kCGDisplaySamplesPerPixel) Specifies a CFNumber integer value that represents the number of samples in a pixel. [`let kCGDisplayShowDuplicateLowResolutionModes: CFString`](/documentation/CoreGraphics/kCGDisplayShowDuplicateLowResolutionModes) [`class let yCbCrMatrix_ITU_R_601_4: CFString`](/documentation/CoreGraphics/CGDisplayStream/yCbCrMatrix_ITU_R_601_4) Specifies the YCbCr to RGB conversion matrix for standard digital television (ITU R 601) images. [`class let yCbCrMatrix_ITU_R_709_2: CFString`](/documentation/CoreGraphics/CGDisplayStream/yCbCrMatrix_ITU_R_709_2) Specifies the YCbCr to RGB conversion matrix for HDTV digital television (ITU R 709) images. [`class let yCbCrMatrix_SMPTE_240M_1995: CFString`](/documentation/CoreGraphics/CGDisplayStream/yCbCrMatrix_SMPTE_240M_1995) Specifies the YCbCR to RGB conversion matrix for 1920 x 1135 HDTV (SMPTE 240M 1995). [`var kCGDisplayWidth: String`](/documentation/CoreGraphics/kCGDisplayWidth) Specifies a CFNumber integer value that represents the width of the display in pixels. [`var kCGFontIndexInvalid: CGFontIndex`](/documentation/CoreGraphics/kCGFontIndexInvalid) An invalid font index (a value which never represents a valid glyph). [`var kCGFontIndexMax: CGFontIndex`](/documentation/CoreGraphics/kCGFontIndexMax) The maximum allowed value of a [`CGFontIndex`](/documentation/CoreGraphics/CGFontIndex). [`var kCGGlyphMax: CGFontIndex`](/documentation/CoreGraphics/kCGGlyphMax) The maximum allowed value of a [`CGGlyph`](/documentation/CoreGraphics/CGGlyph). [`var kCGIODisplayModeID: String`](/documentation/CoreGraphics/kCGIODisplayModeID) [`var kCGMouseDownEventMaskingDeadSwitchTimeout: Double`](/documentation/CoreGraphics/kCGMouseDownEventMaskingDeadSwitchTimeout) [`var kCGNotifyEventTapAdded: String`](/documentation/CoreGraphics/kCGNotifyEventTapAdded) [`var kCGNotifyEventTapRemoved: String`](/documentation/CoreGraphics/kCGNotifyEventTapRemoved) [`var kCGNotifyGUIConsoleSessionChanged: String`](/documentation/CoreGraphics/kCGNotifyGUIConsoleSessionChanged) [`var kCGNotifyGUISessionUserChanged: String`](/documentation/CoreGraphics/kCGNotifyGUISessionUserChanged) [`var kCGNumReservedWindowLevels: Int32`](/documentation/CoreGraphics/kCGNumReservedWindowLevels) [`var kCGSessionConsoleSetKey: String`](/documentation/CoreGraphics/kCGSessionConsoleSetKey) A `CFNumber` 32-bit unsigned integer value that represents a set of hardware composing a console. [`var kCGSessionLoginDoneKey: String`](/documentation/CoreGraphics/kCGSessionLoginDoneKey) A `CFBoolean` value indicating whether the login operation has been done. [`var kCGSessionOnConsoleKey: String`](/documentation/CoreGraphics/kCGSessionOnConsoleKey) A `CFBoolean` value indicating whether the session is on a console. [`var kCGSessionUserIDKey: String`](/documentation/CoreGraphics/kCGSessionUserIDKey) A `CFNumber` 32-bit unsigned integer value that encodes a user ID for the session’s current user. [`var kCGSessionUserNameKey: String`](/documentation/CoreGraphics/kCGSessionUserNameKey) A `CFString` value that encodes the session’s short user name as set by the login operation. [`let kCGWindowAlpha: CFString`](/documentation/CoreGraphics/kCGWindowAlpha) [`let kCGWindowBackingLocationVideoMemory: CFString`](/documentation/CoreGraphics/kCGWindowBackingLocationVideoMemory) [`let kCGWindowBounds: CFString`](/documentation/CoreGraphics/kCGWindowBounds) [`let kCGWindowIsOnscreen: CFString`](/documentation/CoreGraphics/kCGWindowIsOnscreen) [`let kCGWindowLayer: CFString`](/documentation/CoreGraphics/kCGWindowLayer) [`let kCGWindowMemoryUsage: CFString`](/documentation/CoreGraphics/kCGWindowMemoryUsage) [`let kCGWindowName: CFString`](/documentation/CoreGraphics/kCGWindowName) [`let kCGWindowNumber: CFString`](/documentation/CoreGraphics/kCGWindowNumber) [`let kCGWindowOwnerName: CFString`](/documentation/CoreGraphics/kCGWindowOwnerName) [`let kCGWindowOwnerPID: CFString`](/documentation/CoreGraphics/kCGWindowOwnerPID) [`let kCGWindowSharingState: CFString`](/documentation/CoreGraphics/kCGWindowSharingState) [`let kCGWindowStoreType: CFString`](/documentation/CoreGraphics/kCGWindowStoreType) [`let CGPointZero: CGPoint`](/documentation/CoreGraphics/CGPointZero) A point constant with location `(0,0)`. The zero point is equivalent to `CGPointMake(0,0)`. [`let CGRectZero: CGRect`](/documentation/CoreGraphics/CGRectZero) A rectangle constant with location `(0,0)`, and width and height of 0. The zero rectangle is equivalent to `CGRectMake(0,0,0,0)`. [`let CGSizeZero: CGSize`](/documentation/CoreGraphics/CGSizeZero) A size constant with width and height of `0`. The zero size is equivalent to `CGSizeMake(0,0)`. [`let kCGWindowWorkspace: CFString`](/documentation/CoreGraphics/kCGWindowWorkspace) [`var CG_HDR_BT_2100: Int32`](/documentation/CoreGraphics/CG_HDR_BT_2100) [`var kCGBitmapByteOrder16Host: CGBitmapInfo`](/documentation/CoreGraphics/kCGBitmapByteOrder16Host) 16-bit, host endian format. [`var kCGBitmapByteOrder32Host: CGBitmapInfo`](/documentation/CoreGraphics/kCGBitmapByteOrder32Host) 32-bit, host endian format. [`let kCGColorSpaceExtendedRange: CFString`](/documentation/CoreGraphics/kCGColorSpaceExtendedRange) [`var kCGDefaultHDRImageContentHeadroom: Float`](/documentation/CoreGraphics/kCGDefaultHDRImageContentHeadroom) [`let kCGEXRToneMappingGammaDefog: CFString`](/documentation/CoreGraphics/kCGEXRToneMappingGammaDefog) [`let kCGEXRToneMappingGammaExposure: CFString`](/documentation/CoreGraphics/kCGEXRToneMappingGammaExposure) [`let kCGEXRToneMappingGammaKneeHigh: CFString`](/documentation/CoreGraphics/kCGEXRToneMappingGammaKneeHigh) [`let kCGEXRToneMappingGammaKneeLow: CFString`](/documentation/CoreGraphics/kCGEXRToneMappingGammaKneeLow) [`var kCGNullDirectDisplay: CGDirectDisplayID`](/documentation/CoreGraphics/kCGNullDirectDisplay) A value that will never correspond to actual hardware. [`var kCGNullWindowID: CGWindowID`](/documentation/CoreGraphics/kCGNullWindowID) [`var kCGNumReservedBaseWindowLevels: Int32`](/documentation/CoreGraphics/kCGNumReservedBaseWindowLevels) [`let kCGPDFContextAccessPermissions: CFString`](/documentation/CoreGraphics/kCGPDFContextAccessPermissions) [`let kCGPDFContextCreateLinearizedPDF: CFString`](/documentation/CoreGraphics/kCGPDFContextCreateLinearizedPDF) [`let kCGPDFContextCreatePDFA: CFString`](/documentation/CoreGraphics/kCGPDFContextCreatePDFA) [`let kCGPDFOutlineChildren: CFString`](/documentation/CoreGraphics/kCGPDFOutlineChildren) [`let kCGPDFOutlineDestination: CFString`](/documentation/CoreGraphics/kCGPDFOutlineDestination) [`let kCGPDFOutlineDestinationRect: CFString`](/documentation/CoreGraphics/kCGPDFOutlineDestinationRect) [`let kCGPDFOutlineTitle: CFString`](/documentation/CoreGraphics/kCGPDFOutlineTitle) [`let kCGSkipBoostToHDR: CFString`](/documentation/CoreGraphics/kCGSkipBoostToHDR) [`let kCGUse100nitsHLGOOTF: CFString`](/documentation/CoreGraphics/kCGUse100nitsHLGOOTF) [`let kCGUseBT1886ForCoreVideoGamma: CFString`](/documentation/CoreGraphics/kCGUseBT1886ForCoreVideoGamma) [`let kCGUseLegacyHDREcosystem: CFString`](/documentation/CoreGraphics/kCGUseLegacyHDREcosystem) [`var kCGAssistiveTechHighWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGAssistiveTechHighWindowLevel) [`var kCGBackstopMenuLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGBackstopMenuLevel) [`#define kCGBaseWindowLevel`](/documentation/CoreGraphics/kCGBaseWindowLevel) [`#define kCGCursorWindowLevel`](/documentation/CoreGraphics/kCGCursorWindowLevel) [`#define kCGDesktopIconWindowLevel`](/documentation/CoreGraphics/kCGDesktopIconWindowLevel) [`#define kCGDesktopWindowLevel`](/documentation/CoreGraphics/kCGDesktopWindowLevel) [`var kCGDockWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGDockWindowLevel) [`var kCGDraggingWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGDraggingWindowLevel) [`var kCGFloatingWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGFloatingWindowLevel) [`var kCGHelpWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGHelpWindowLevel) [`var kCGMainMenuWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGMainMenuWindowLevel) [`#define kCGMaximumWindowLevel`](/documentation/CoreGraphics/kCGMaximumWindowLevel) [`#define kCGMinimumWindowLevel`](/documentation/CoreGraphics/kCGMinimumWindowLevel) [`var kCGModalPanelWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGModalPanelWindowLevel) [`var kCGNormalWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGNormalWindowLevel) [`var kCGOverlayWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGOverlayWindowLevel) [`var kCGPopUpMenuWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGPopUpMenuWindowLevel) [`var kCGScreenSaverWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGScreenSaverWindowLevel) [`var kCGStatusWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGStatusWindowLevel) [`var kCGTornOffMenuWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGTornOffMenuWindowLevel) [`var kCGUtilityWindowLevel: CGWindowLevel`](/documentation/CoreGraphics/kCGUtilityWindowLevel) [`#define CGDisplayNoErr`](/documentation/CoreGraphics/CGDisplayNoErr) [`#define CGEventNoErr`](/documentation/CoreGraphics/CGEventNoErr) --- Copyright © 2026 Apple Inc. 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