Package org.ghost4j.display
Interface DisplayCallback
- All Known Implementing Classes:
ImageWriterDisplayCallback
,PageRasterDisplayCallback
public interface DisplayCallback
Interface representing a display callback. A display callback provides method
to interract with the Ghostscript interpreter display. This can be usefull if
you are interested in capturing PS or PDF page rasters. Important: in order
to use a display callback, Ghostscript must be initialized with
-sDEVICE=display -sDisplayHandle and -dDisplayFormat arguments. Usually set
-sDisplayHandle to 0 and use -dDisplayFormat to define how display data will
be sent to the displayPage method. -dDisplayFormat=16#804 sets a standard RGB
ouput. Please refer to http://ghostscript.com/doc/8.54/Devices.htm to see how
to set display parameters.
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Method Summary
Modifier and TypeMethodDescriptionvoid
Method called when device has been closed.void
Method called when new device has been opened.void
displayPage
(int width, int height, int raster, int format, int copies, int flush, byte[] imageData) Method called on show page.void
Method called when device is about to be closed.void
displayPreSize
(int width, int height, int raster, int format) Method called when device is about to be resized.void
displaySize
(int width, int height, int raster, int format) Method called when device has been resized.void
Method called on page flush.void
displayUpdate
(int x, int y, int width, int height) Method called to notify whenever a portion of the raster is updated.
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Method Details
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displayOpen
Method called when new device has been opened. This is the first event from this device.- Throws:
GhostscriptException
-
displayPreClose
Method called when device is about to be closed. Device will not be closed until this function returns.- Throws:
GhostscriptException
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displayClose
Method called when device has been closed. This is the last event from this device.- Throws:
GhostscriptException
-
displayPreSize
Method called when device is about to be resized.- Parameters:
width
- Widthheight
- Heightraster
- Rasterformat
- Format- Throws:
GhostscriptException
-
displaySize
Method called when device has been resized.- Parameters:
width
- Widthheight
- Heightraster
- Rasterformat
- Format- Throws:
GhostscriptException
-
displaySync
Method called on page flush.- Throws:
GhostscriptException
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displayPage
void displayPage(int width, int height, int raster, int format, int copies, int flush, byte[] imageData) throws GhostscriptException Method called on show page.- Parameters:
width
- Widthheight
- Heightraster
- Rasterformat
- Formatcopies
- Copiesflush
- FlushimageData
- Byte array representing image data. Data layout and order is controlled by the -dDisplayFormat argument.- Throws:
GhostscriptException
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displayUpdate
Method called to notify whenever a portion of the raster is updated.- Parameters:
x
- X coordinatey
- Y coordinatewidth
- Widthheight
- Height- Throws:
GhostscriptException
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