Document Revision History

This table describes the changes to CGContext Reference.

Date	Notes
2009-05-26	Updated function discussions to account for coordinate system differences between iPhone OS and Mac OS X.
2008-04-08	Made a minor typographical change.
2007-07-17	Updated for Mac OS X v10.5.
	All instances of the `float` data type were changed to the `CGFloat` data type.
	Added the Porter-Duff blend modes to `“Blend Modes”`.
	Added `CGContextDrawLinearGradient`, `CGContextDrawRadialGradient`, `CGContextDrawTiledImage`, `CGContextShowGlyphsAtPositions`, and `CGContextBeginTransparencyLayerWithRect`.
	Modified the description of the auxiliaryInfo parameter in `CGContextBeginTransparencyLayer`.
	Added a performance tip to `CGContextBeginTransparencyLayer`.
	Clarified the definition of “inside” for `CGContextPathContainsPoint`.
2006-01-10	Added information to the discussion for blend mode constants.
	Improved wording concerning text clipping in “Text Drawing Modes.”
2005-11-09	Revised information about text space and user space.
2005-04-29	Updated for Mac OS X v10.4.
	Added the functions `CGContextSetBlendMode`, `CGContextAddEllipseInRect`, `CGContextReplacePathWithStrokedPath`, `CGContextPathContainsPoint`, `CGContextFillEllipseInRect`, `CGContextStrokeEllipseInRect`, `CGContextStrokeLineSegments`, `CGContextClipToMask`, `CGContextSetAllowsAntialiasing`, `CGContextGetUserSpaceToDeviceSpaceTransform`, `CGContextConvertPointToDeviceSpace`, `CGContextConvertPointToUserSpace`, `CGContextConvertSizeToDeviceSpace`, `CGContextConvertSizeToUserSpace`, `CGContextConvertRectToDeviceSpace`, and `CGContextConvertRectToUserSpace`.
	Added constants for `“Blend Modes”`.
	Changed the description of what to pass for the `components` parameter for the functions `CGContextSetFillPattern` and `CGContextSetStrokePattern`.
2004-08-31	Updated graphics context information and added cross references to conceptual documentation.
2004-02-26	First version of this document. An earlier version of this information appeared in Quartz 2D Reference.