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DynaPDF Manual - Page 571

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Function Reference
Page 571 of 750
rfRotate180
= 0x00000200, // Rotate the page by 180 degress
rfRotate270
= 0x00000400, // Rotate the page by 270 degress
rfInitBlack
= 0x00000800, // Initialize the image buffer to black
// before rendering. This flag is not
// meaningful if the pixel format has
// no alpha channel.
rfCompositeWhite
= 0x00001000, // Composite the image with a white
// background after rendering. This
// flag is meaningful only for pixel
// formats with an alpha channel.
rfExclPageContent = 0x00002000, // If set, only annotations and form fields will be rendered
rfExclButtons
= 0x00004000, // Exclude push buttons
rfExclCheckBoxes
= 0x00008000, // Exclude check boxes
rfExclComboBoxes
= 0x00010000, // Exclude combo boxes
rfExclListBoxes
= 0x00020000, // Exclude list boxes
rfExclTextFields
= 0x00040000, // Exclude text fields
rfExclSigFields
= 0x00080000, // Exclude signature fields
// ---------------------------------
rfScaleToBBox
= 0x00100000, // Meaningful only, if rfClipToArtBox, rfClipToBleedBox, or
// rfClipToTrimBox is set. If set, the picture size is set to the
// size of the whished bounding box.
rfDisableAAClipping
= 0x00200000, // Disable Anti-Aliasing for clipping paths. This flag is
// the most important one since clipping paths cause often
// visible artefacts in PDF files with flattened
// transparency.
rfDisableAAText
= 0x00400000, // Disable Anti-Aliasing for text.
rfDisableAAVector
= 0x00800000, // Disable Anti-Aliasing for vector graphics.
// Fully disable Anti-Aliasing.
rfDisableAntiAliasing
= rfDisableAAClipping | rfDisableAAText | rfDisableAAVector,
rfDisableBiLinearFilter = 0x01000000, // Disable the BiLevel filter for images. Sometimes useful
// if sharp images are needed, e.g. for barcodes.
rfClipBoxMask
= rfClipToArtBox | rfClipToBleedBox | rfClipToTrimBox // Internal flags
}TRasterFlags;
typedef SI32 PDF_CALL TOnUpdateWindow(const void* Data, TIntRect Area);
The function renders a PDF page into an image buffer. This function was mainly designed to render
PDF pages in a viewer application but it can also be used for other purposes where fast rendering
into an image buffer is required. It is also possible to render pages into a device context, see
RenderPageEx() for further information.
Before rendering the first page the application should set the path from which external CMaps can
be loaded (see SetCMapDir()). Set the path with the flag lcmDelayed so that the files will only be
loaded if necessary.
It is also strongly recommended to initialize the color management before rendering the first page
(see InitColorManagement()). The output intent (if any) will be loaded automatically before the page
will be rendered if color management is enabled.
Minimal initialization
A few members of the the structure TPDFRasterImage must be correctly initialized, otherwise
nothing can be rendered:
TPDFRasterImage img;
memset(&img, 0, sizeof(img));
img.StructSize = sizeof(img);
img.Matrix.a
= 1.0; // Identity matrix
img.Matrix.d
= 1.0; // Identity matrix (1.0, 0.0, 0.0, 1.0, 0.0, 0.0)
 

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