IDWriteBitmapRenderTarget::DrawGlyphRun Method

Draws a run of glyphs to a bitmap target at the specified position.

Syntax

virtual HRESULT DrawGlyphRun(
  FLOAT  baselineOriginX,
  FLOAT  baselineOriginY,
  DWRITE_MEASURING_MODE  measuringMode,
  [in]             const DWRITE_GLYPH_RUN * glyphRun,
  IDWriteRenderingParams * renderingParams,
  COLORREF  textColor,
  [out, optional]  RECT * blackBoxRect
) = 0;

Parameter

• baselineOriginX
  The horizontal position of the baseline origin, in DIPs, relative to the upper-left corner of the DIB.

• baselineOriginY
  The vertical position of the baseline origin, in DIPs, relative to the upper-left corner of the DIB.

• measuringMode
  The measuring method for glyphs in the run, used with the other properties to determine the rendering mode.

• glyphRun [in]
  The structure containing the properties of the glyph run.

• renderingParams
  The object that controls rendering behavior.

• textColor
  The foreground color of the text.

• blackBoxRect [out, optional]
  The optional rectangle that receives the bounding box (in pixels not DIPs) of all the pixels affected by drawing the glyph run. The black box rectangle may extend beyond the dimensions of the bitmap.

Rückgabewert

Ist Methode erfolgreich, wird "S_OK" zurückgegeben. Andernfalls wird ein HRESULT-Fehlercode zurückgegeben.

Hinweise

You can use the IDWriteBitmapRenderTarget::DrawGlyphRun to render to a bitmap from a custom text renderer that you implement. The custom text renderer should call this method from within the IDWriteTextRenderer::DrawGlyphRun callback method as shown in the following code.

STDMETHODIMP GdiTextRenderer::DrawGlyphRun(
    __maybenull void* clientDrawingContext,
    FLOAT baselineOriginX,
    FLOAT baselineOriginY,
    DWRITE_MEASURING_MODE measuringMode,
    __in DWRITE_GLYPH_RUN const* glyphRun,
    __in DWRITE_GLYPH_RUN_DESCRIPTION const* glyphRunDescription,
    IUnknown* clientDrawingEffect
    )
{
    HRESULT hr = S_OK;

    // Pass on the drawing call to the render target to do the real work.
    RECT dirtyRect = {0};

    hr = pRenderTarget_->DrawGlyphRun(
        baselineOriginX,
        baselineOriginY,
        measuringMode,
        glyphRun,
        pRenderingParams_,
        RGB(0,200,255),
        &dirtyRect
        );
    

    return hr;
}

The baselineOriginX, baslineOriginY, measuringMethod, and glyphRun parameters are provided (as arguments) when the callback method is invoked. The renderingParams, textColor and blackBoxRect are not.

Default rendering params can be retrieved by using the IDWriteFactory::CreateMonitorRenderingParams method.

Anforderungen

Siehe auch

IDWriteBitmapRenderTarget