Editing ClearType (section)

==Implementations==
* [[Windows XP]] (off by default)
* [[Windows Vista]] (on by default)
* [[Windows 7]] (on by default)
* [[Windows 8]]: Only used in Windows 8 Desktop and all desktop apps<ref name="something">[http://www.istartedsomething.com/20120303/cleartype-takes-a-back-seat-for-windows-8-metro/ ClearType takes a back seat for Windows 8 Metro]</ref>
* [[Windows 10]]: Only used in Win32 apps and Win32 system features, not Universal Windows Platform.
* [[Internet Explorer 7]] and later (on by default)
* [[Microsoft Office 2007]] and 2010 (on by default)
* [[Windows Live Messenger]] (on by default)
* [[Microsoft Reader]]

ClearType is also an integrated component of the [[Windows Presentation Foundation]] text-rendering engine.

===ClearType Font Collection===
As part of the Vista release, Microsoft released a set of fonts, known as the ''ClearType Font Collection'', thought to work well with the ClearType system:<ref name="NowReadThis">{{cite book|last1=Berry|first1=John D.|title=Now Read This: the Microsoft ClearType Collection|publisher=Microsoft Corp|year=2004|url=https://docs.microsoft.com/en-us/typography/cleartype/clear-type-font-collection|location=Redmond, WA}}</ref><ref>{{cite web|last1=Levien|first1=Raph|author-link=Raph Levien|title=Microsoft's ClearType Font Collection: A Fair and Balanced Review|url=http://typographica.org/on-typography/microsofts-cleartype-font-collection-a-fair-and-balanced-review/|website=Typographica|access-date=24 November 2014}}</ref>
* [[Calibri]]
* [[Cambria (typeface)|Cambria]]
* [[Candara]]
* [[Consolas]]
* [[Constantia (typeface)|Constantia]]
* [[Corbel (typeface)|Corbel]]
* [[Meiryo]]

Fonts included by some, but not always part of the set:
* Cariadings<ref>{{cite web |author1=Microsoft Corporation |title=Microsoft ClearType Font Collection |url=http://www.ascendercorp.com/pdf/MSClearTypeFontCollection.pdf |website=Ascender Corp. |publisher=Ascender Corporation |access-date=8 March 2021 |archive-url=https://web.archive.org/web/20081221072417/http://www.ascendercorp.com/pdf/MSClearTypeFontCollection.pdf |archive-date=21 December 2008 |pages=16–17 |date=2006–2007 |url-status=dead}}</ref>
* [[Malgun Gothic]]
* [[Microsoft JhengHei]]
* [[Microsoft YaHei]]
* [[Segoe]]

===ClearType in GDI===
ClearType can be globally enabled or disabled for [[Graphics Device Interface|GDI]] applications. A control panel applet is available to let the users tune the GDI ClearType settings. The GDI implementation of ClearType does not support sub-pixel positioning.<ref>[http://msdn.microsoft.com/en-us/library/ms749295.aspx Windows Presentation Foundation ClearType Overview]</ref>

===ClearType tuning===
[[Windows XP]], as supplied, allow ClearType to be turned on or off, with no adjustment; [[Windows 7]] and later allow tuning of the ClearType parameters in Control Panel. A Microsoft ClearType tuner utility is available for free download for Windows versions lacking this facility.<ref>{{cite web | url = http://www.microsoft.com/typography/ClearTypePowerToy.mspx | title = Microsoft's ClearType Tuner PowerToy | website = [[Microsoft]] | access-date = 2007-09-27}}</ref> If ClearType is disabled in the operating system, applications with their own ClearType controls can still support it. [[Microsoft Reader]] (for [[e-book]]s) has its own ClearType tuner.

===ClearType in WPF===
All text in [[Windows Presentation Foundation]] is anti-aliased and rendered using ClearType. There are separate ClearType registry settings for GDI and WPF applications, but by default the WPF entries are absent, and the GDI values are used in their absence. WPF registry entries can be tuned using the instructions<ref>[http://blogs.msdn.com/text/archive/2006/10/18/tips-for-improving-your-wpf-text-rendering-experience.aspx Tips for improving your WPF text rendering experience]</ref> from the MSDN WPF Text Blog.

ClearType in WPF supports sub-pixel positioning, natural advance widths, Y-direction [[anti-aliasing]] and [[hardware acceleration]]. WPF supports aggressive caching of pre-rendered ClearType text in video memory.<ref>[http://msdn2.microsoft.com/en-us/library/ms749295.aspx MSDN Library : .NET Development : WPF : ClearType Overview]</ref> The extent to which this is supported is dependent on the [[video card]]. [[DirectX]] 10 cards will be able to cache the font glyphs in video memory, then perform the composition (assembling of character glyphs in the correct order, with the correct spacing), [[alpha blending]] (application of [[anti-aliasing]]), and RGB blending (ClearType's sub-pixel color calculations), entirely in hardware. This means that only the original glyphs need to be stored in video memory once per font (Microsoft estimates that this would require 2&nbsp;MB of video memory per font), and other operations such as the display of anti-aliased text on top of other graphics{{snd}} including video{{snd}} can also be done with no computation effort on the part of the CPU. DirectX 9 cards will only be able to cache the alpha-blended glyphs in memory, thus requiring the CPU to handle glyph composition and alpha-blending before passing this to the video card.  Caching these partially rendered glyphs requires significantly more memory (Microsoft estimates 5&nbsp;MB per process). Cards that don't support DirectX 9 have no hardware-accelerated text rendering capabilities.

===ClearType in DirectWrite===

As pixel densities of displays improved and more high DPI screens became available, colored subpixel rendering became less of a necessity according to Microsoft. Also Windows tablet user interfaces evolved to support vertical screen orientations where the LCD color stripes would run horizontally. The original colored ClearType subpixel rendering was tuned to work optimally with horizontal orientation LCD displays where RGB or BGR stripes run vertically. For these reasons, DirectWrite which is the next-generation text rendering API from Microsoft moved away from color-aware ClearType. The font rendering engine in [[DirectWrite]] supports a different version of ClearType with only greyscale [[anti-aliasing]],<ref>[Office 2013: Further Evidence of the Demise of ClearType? Office 2013: Further Evidence of the Demise of ClearType?]</ref> not color subpixel rendering, as demonstrated at [[Professional Developers Conference|PDC]] 2008.<ref name=DirectWrite>{{cite web|url=http://channel9.msdn.com/pdc2008/PC18|title=PC18: Introducing Direct2D and DirectWrite|author=Kam VedBrat, Leonardo Blanco|publisher=Microsoft|date=2008-10-28}}</ref> This version is sometimes called ''Natural ClearType'' but is often referred to simply as DirectWrite rendering (with the term "ClearType" being designated to only the RGB/BGR color subpixel rendering version).<ref>{{Cite web | url=http://blogs.msdn.com/b/e7/archive/2009/02/13/advances-in-typography-and-text-rendering-in-windows-7.aspx | title=Archived MSDN and TechNet Blogs}}</ref> The improvements have been confirmed by independent sources, such as [[Firefox]] developers;<ref>{{Cite web | url=http://www.basschouten.com/blog1.php/font-rendering-gdi-versus-directwrite |title = Font Rendering: GDI versus DirectWrite}}</ref> they were particularly noticeable for OpenType fonts in [[Compact Font Format]] (CFF).<ref>{{Cite web |url=https://blog.mozilla.org/nattokirai/2009/10/22/better-postscript-cff-font-rendering-with-directwrite/ |title=Archived copy |access-date=2014-08-11 |archive-url=https://web.archive.org/web/20140812210421/https://blog.mozilla.org/nattokirai/2009/10/22/better-postscript-cff-font-rendering-with-directwrite/ |archive-date=2014-08-12 |url-status=dead }}</ref><ref>{{Cite web | url=http://blog.typekit.com/2010/11/12/microsoft-directwrite-is-coming/ |title = Microsoft DirectWrite is Coming|date = 12 November 2010}}</ref>

Many Office 2013 apps including [[Word 2013]], Excel 2013, parts of Outlook 2013 stopped using ClearType and switched to this DirectWrite greyscale antialiasing. The reasons invoked are, in the words of Murray Sargent: "There is a problem with ClearType: it depends critically on the color of the background pixels. This isn’t a problem if you know a priori that those pixels are white, which is usually the case for text. But the general case involves calculating what the colors should be for an arbitrary background and that takes time. Meanwhile, Word 2013 enjoys cool animations and smooth zooming. Nothing jumps any more. Even the caret (the blinking vertical line at the text insertion point) glides from one position to the next as you type. Jerking movement just isn’t considered cool any more. Well animations and zooms have to be faster than human response times in order to appear smooth. And that rules out ClearType in animated scenarios at least with present generation hardware. And in future scenarios, screens will have sufficiently high resolution that gray-scale [[anti-aliasing]] should suffice."<ref name="Word">{{Cite web|url=http://blogs.msdn.com/b/murrays/archive/2014/05/31/crisp-text-display.aspx|title=Crisp Text Display|last=Sargent|first=Murray|url-status=dead|archive-url=https://web.archive.org/web/20150530145657/http://blogs.msdn.com/b/murrays/archive/2014/05/31/crisp-text-display.aspx|archive-date=2015-05-30}}</ref>

For the same reasons related to animation performance and vertical screen orientations where the colored RGB/BGR ClearType antialiasing would be a problem, the color-aware version of ClearType was abandoned in Metro-style apps platform of Windows 8 (and Universal Windows Platform of Windows 10).,<ref>[https://blogs.msdn.microsoft.com/oldnewthing/20150129-00/?p=44803 Color-aware ClearType requires access to fixed background pixels, which is a problem if you don’t know what the background pixels are, or if they aren’t fixed]</ref><ref name="something"/> including the Start menu and everything not using classic Win32 APIs (GDI/GDI+).