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IDWriteFactory::CreateGlyphRunAnalysis method (dwrite.h)

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Creates a glyph run analysis object, which encapsulates information used to render a glyph run.

Syntax

HRESULT CreateGlyphRunAnalysis(
  [in]           DWRITE_GLYPH_RUN const  *glyphRun,
                 FLOAT                   pixelsPerDip,
  [in, optional] DWRITE_MATRIX const     *transform,
                 DWRITE_RENDERING_MODE   renderingMode,
                 DWRITE_MEASURING_MODE   measuringMode,
                 FLOAT                   baselineOriginX,
                 FLOAT                   baselineOriginY,
  [out]          IDWriteGlyphRunAnalysis **glyphRunAnalysis
);

Parameters

[in] glyphRun

Type: const DWRITE_GLYPH_RUN*

A structure that contains the properties of the glyph run (font face, advances, and so on).

pixelsPerDip

Type: FLOAT

Number of physical pixels per DIP (device independent pixel). For example, if rendering onto a 96 DPI bitmap then pixelsPerDip is 1. If rendering onto a 120 DPI bitmap then pixelsPerDip is 1.25.

[in, optional] transform

Type: const DWRITE_MATRIX*

Optional transform applied to the glyphs and their positions. This transform is applied after the scaling specified the emSize and pixelsPerDip.

renderingMode

Type: DWRITE_RENDERING_MODE

A value that specifies the rendering mode, which must be one of the raster rendering modes (that is, not default and not outline).

measuringMode

Type: DWRITE_MEASURING_MODE

Specifies the measuring mode to use with glyphs.

baselineOriginX

Type: FLOAT

The horizontal position (X-coordinate) of the baseline origin, in DIPs.

baselineOriginY

Type: FLOAT

Vertical position (Y-coordinate) of the baseline origin, in DIPs.

[out] glyphRunAnalysis

Type: IDWriteGlyphRunAnalysis**

When this method returns, contains an address of a pointer to the newly created glyph run analysis object.

Return value

Type: HRESULT

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

Remarks

The glyph run analysis object contains the results of analyzing the glyph run, including the positions of all the glyphs and references to all of the rasterized glyphs in the font cache.

Examples

The following code example shows how to create a glyph run analysis object. In this example, an empty glyph run is being used.

HRESULT CreateGlyphRunAnalysis(IDWriteFontFace *pFontFace, IDWriteGlyphRunAnalysis **ppGlyphRunAnalysis)
{
    HRESULT hr = S_OK;
    IDWriteFactory* pDWriteFactory = NULL;

    // Create the DirectWrite factory.
    hr = DWriteCreateFactory(
            DWRITE_FACTORY_TYPE_SHARED,
            __uuidof(IDWriteFactory),
            reinterpret_cast<IUnknown**>(&pDWriteFactory)
            );

    DWRITE_GLYPH_RUN emptyGlyphRun = { 0 };
    UINT16 glyphIndex = 0;
    
    emptyGlyphRun.fontFace = pFontFace;
    emptyGlyphRun.glyphIndices = &glyphIndex;
    emptyGlyphRun.glyphCount = 0;
   
    emptyGlyphRun.fontEmSize = 12;

    IDWriteGlyphRunAnalysis* pGlyphRunAnalysis = NULL;

    if (SUCCEEDED(hr))
    {
        hr = pDWriteFactory->CreateGlyphRunAnalysis(
            &emptyGlyphRun,
            1.0f, // pixelsPerDip,
            NULL, // transform,
            DWRITE_RENDERING_MODE_CLEARTYPE_GDI_CLASSIC,
            DWRITE_MEASURING_MODE_GDI_CLASSIC,
            0.0f, // baselineOriginX,
            0.0f, // baselineOriginY,
            &pGlyphRunAnalysis);
    }
    
    *ppGlyphRunAnalysis = pGlyphRunAnalysis;

    SafeRelease(&pDWriteFactory);

    return S_OK;
}

Requirements

Requirement Value
Minimum supported client Windows 7, Windows Vista with SP2 and Platform Update for Windows Vista [desktop apps | UWP apps]
Minimum supported server Windows Server 2008 R2, Windows Server 2008 with SP2 and Platform Update for Windows Server 2008 [desktop apps | UWP apps]
Target Platform Windows
Header dwrite.h
Library Dwrite.lib
DLL Dwrite.dll

See also

IDWriteFactory