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XpSetImageResolution

Section: XPRINT FUNCTIONS (3Xp)
Updated: libXp 1.0.3
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NAME

XpSetImageResolution - Sets the resolution for subsequent PutImage requests

SYNOPSIS

cc [ flag... ] file... -lXp [ library... ]

#include <X11/extensions/Print.h>

Bool XpSetImageResolution ( display, print_context, image_res, prev_res_return )

      Display * display ;

      XPContext  print_context ;

      int  image_res ;

      int * prev_res_return ;

ARGUMENTS

- display: Specifies a pointer to the Display structure.
- print_context: Specifies the print context on which to set the resolution.
- image_res: Specifies the image resolution in pixels per inch.
- prev_res_return: Returns the previous image resolution in pixels per inch.

DESCRIPTION

XpSetImageResolution returns True if the printer server allowed the resolution to be set, otherwise False is returned.

XpSetImageResolution sets the resolution for subsequent PutImage requests to the screen of the specified print context. If the return value is False, then the print server does not support image scaling for the particular resolution given the current configuration of the printer, and the application is responsible for any desired scaling. If the return value is True, then the contents of any subsequent PutImage request to a Pixmap or to a Window on the screen of the specified print context will automatically be scaled as part of the PutImage request. The scale factor is:

    default_printer_resolution / image_res

Where default_printer_resolution is the current value of that page attribute. Only the image itself is scaled (meaning the effective width and height of the image change), the dst-x and dst-y parameters to PutImage are not altered.

As a special case, a value of zero for image_res resets the resolution to automatically track the printer resolution; in this case (which is also the default setting for a newly created print context), subsequent images will not be scaled.

If the return value is True and prev_res_return is a non-NULL pointer, then the previous image resolution that was set for the print context is stored in prev_res_return.

XpSetImageResolution returns False immediately if image_res is negative or greater than 65535.

DIAGNOSTICS

XpBadContext: A valid print context-id has not been set prior to making this call.