PreviewFilterJPEG Class Reference

The filter will save out the JPEG Preview Bitmap. Overrides GetExportOptions so dialogs are not put up but returns preview export options. Note: 22/01/97 Preview filters can generally import as well now (if their base class can) but obviously this one can't - use JPEGImportFilter instead. More...

#include <prvwflt.h>

Inheritance diagram for PreviewFilterJPEG:

List of all members.

Public Member Functions
	PreviewFilterJPEG ()
	Constructor for an PreviewFilterJPEG object. The object should be initialised before use.
BOOL	Init ()
	Initialise an PreviewFilter object.
virtual BOOL	DoExport (Operation *, CCLexFile *, PathName *, Document *, BOOL)
	Do some set up before exporting so the BaseBitmapFilter base class knows it is really a preview. The BaseBitmapFilter can then do resizing as necessary.
Protected Member Functions
virtual BOOL	GetExportOptions (BitmapExportOptions *pOptions)
	Override base class so we don't put up a dialog but still provide fixed options for preview bitmap filters. Notes: See BaseBitmapFilter for interface details.
Private Member Functions
	CC_DECLARE_MEMDUMP (PreviewFilterJPEG)

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Detailed Description

The filter will save out the JPEG Preview Bitmap. Overrides GetExportOptions so dialogs are not put up but returns preview export options. Note: 22/01/97 Preview filters can generally import as well now (if their base class can) but obviously this one can't - use JPEGImportFilter instead.

Author:

Neville_Humphrys (Xara Group Ltd) <camelotdev@xara.com>

Date:

24/6/95

Definition at line 221 of file prvwflt.h.

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Constructor & Destructor Documentation

PreviewFilterJPEG::PreviewFilterJPEG (   )

Constructor for an PreviewFilterJPEG object. The object should be initialised before use. / /*! Author: Neville_Humphrys (Xara Group Ltd) <camelotdev@xara.com> Date: 24/6/95 See also: PreviewFilterJPEG::Init Definition at line 626 of file prvwflt.cpp. : JPEGExportFilter() { ImportMsgID = _R(IDN_IMPORTMSG_JPEG); // Set it up so that it can neither Import or Export so that it does not appear in the // Filter menus. Flags.CanImport = FALSE; Flags.CanExport = FALSE; FilterID = FILTERID_PREVIEW_JPEG; ExportRegion = NULL; ExportMsgID = _R(IDS_BUILDINGPREVIEW); ExportingMsgID = _R(IDS_BUILDINGPREVIEW); }

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Member Function Documentation

PreviewFilterJPEG::CC_DECLARE_MEMDUMP (  PreviewFilterJPEG   )  [private]

BOOL PreviewFilterJPEG::DoExport (  Operation *  pOp, CCLexFile *  pFile, PathName *  pPath, Document *  TheDocument, BOOL  ShowOptions )  [virtual]

Do some set up before exporting so the BaseBitmapFilter base class knows it is really a preview. The BaseBitmapFilter can then do resizing as necessary. Author: Martin_Bell (Xara Group Ltd) <camelotdev@xara.com> Date: 30/01/97 Notes: copied from BaseCamelotFilter::ExportPreviewBitmap which does the set up for us usually (why?). We repeat it here so the _BATCHING thumnail generation stuff is the right size as well. Reimplemented from BaseBitmapFilter. Definition at line 686 of file prvwflt.cpp. { INT32 OldPreviewSize = PreviewFilter::PreviewBitmapSize; // Set the Preview to be just over an inch accross PreviewFilter::PreviewBitmapSize = 96000; // set ourselves up - this flags the BaseBitmapFilter to do resizing, which needs to be // done there because of Accusoft. SetPreviewBitmap(TRUE); // Export the Preview to the file by doing what our base class does BOOL ok = JPEGExportFilter::DoExport(pOp, pFile, pPath, TheDocument, TRUE); // Set ourselves back SetPreviewBitmap(FALSE); // Set the Preview back to its default setting PreviewFilter::PreviewBitmapSize = OldPreviewSize; return ok; }

BOOL PreviewFilterJPEG::GetExportOptions (  BitmapExportOptions *  pOptions  )  [protected, virtual]

Override base class so we don't put up a dialog but still provide fixed options for preview bitmap filters. Notes: See BaseBitmapFilter for interface details. Author: Martin_Bell (Xara Group Ltd) <camelotdev@xara.com> Date: 15/01/97 Reimplemented from JPEGExportFilter. Definition at line 720 of file prvwflt.cpp. { ERROR2IF(pOptions == NULL, FALSE, "NULL Args"); ERROR3IF(!pOptions->IS_KIND_OF(JPEGExportOptions), "pOptions isn't a JPEGExportOptions"); JPEGExportOptions* pJPEGOptions = (JPEGExportOptions*)pOptions; // the depth we ask GDraw to render is always 32-bit, so we can get transparency // we have to convert for other formats when writing the actual bytes to the file SetDepthToRender(32); // We haven't written the header yet WrittenHeader = FALSE; // BitmapExportOptions // // this dpi will be used to scale the preview pJPEGOptions->SetDPI(96.0); // the export depth of the preview is always 8 pJPEGOptions->SetDepth(8); // I'm fairly sure this isn't used for anything in WEBSTER-Martin-17/01/97 //PreviewDither = ?; PreviewPalette = PAL_OPTIMISED; // JPEGExportOptions // // Previews have an optimized palette PaletteType = PreviewPalette; return TRUE; }

BOOL PreviewFilterJPEG::Init (  void   )  [virtual]

Initialise an PreviewFilter object. Author: Neville_Humphrys (Xara Group Ltd) <camelotdev@xara.com> Date: 24/6/95 Returns: TRUE if the filter was initialised ok, FALSE otherwise. Errors: Will fail if not enough memory to initialise. See also: BMPFilter::Init() Reimplemented from JPEGExportFilter. Definition at line 654 of file prvwflt.cpp. { // Get the OILFilter object pOILFilter = new JPEGOILFilter(this); if (pOILFilter==NULL) return FALSE; // Load the description strings FilterName.Load(_R(IDN_JPEG_FILTERNAME)); FilterInfo.Load(_R(IDN_JPEG_FILTERINFO)); // All ok return TRUE; }

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The documentation for this class was generated from the following files:

• Kernel/prvwflt.h (r1785/r809)
• Kernel/prvwflt.cpp (r1785/r1282)

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