man/man3/GetImage.3 - toolchains/skids - Git at Google

 '\"
 '\" Copyright (c) 1994 The Regents of the University of California.
 '\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
 '\"
 '\" See the file "license.terms" for information on usage and redistribution
 '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 '\"
 '\" RCS: @(#) $Id: GetImage.3,v 1.5 2002/08/05 04:30:38 dgp Exp $
 '\"
 '\" The definitions below are for supplemental macros used in Tcl/Tk
 '\" manual entries.
 '\"
 '\" .AP type name in/out ?indent?
 '\"	Start paragraph describing an argument to a library procedure.
 '\"	type is type of argument (int, etc.), in/out is either "in", "out",
 '\"	or "in/out" to describe whether procedure reads or modifies arg,
 '\"	and indent is equivalent to second arg of .IP (shouldn't ever be
 '\"	needed;  use .AS below instead)
 '\"
 '\" .AS ?type? ?name?
 '\"	Give maximum sizes of arguments for setting tab stops.  Type and
 '\"	name are examples of largest possible arguments that will be passed
 '\"	to .AP later.  If args are omitted, default tab stops are used.
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 '\"	End of list of standard options for a Tk widget.
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 '\" .OP cmdName dbName dbClass
 '\"	Start of description of a specific option.  cmdName gives the
 '\"	option's name as specified in the class command, dbName gives
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 '\"	the option's class in the option database.
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 '\" .UL arg1 arg2
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 '\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
 '\"
 '\"	# Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
 .if t .wh -1.3i ^B
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 '\"	# Start an argument description
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 .ie !"\\$4"" .TP \\$4
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 .   ie !"\\$2"" .TP \\n()Cu
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 .\}
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 ..
 .AS Tcl_Interp Tcl_CreateInterp in/out
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 .\}
 .el \}\
 \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
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 See the \\fBoptions\\fR manual entry for details on the standard options.
 ..
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 .TH Tk_GetImage 3 4.0 Tk "Tk Library Procedures"
 .BS
 .SH NAME
 Tk_GetImage, Tk_RedrawImage, Tk_SizeOfImage, Tk_FreeImage \- use an image in a widget
 .SH SYNOPSIS
 .nf
 \fB#include <tk.h>\fR
 .sp
 Tk_Image
 \fBTk_GetImage\fR(\fIinterp, tkwin, name, changeProc, clientData\fR)
 .sp
 \fBTk_RedrawImage\fR(\fIimage, imageX, imageY, width, height, drawable, drawableX, drawableY\fR)
 .sp
 \fBTk_SizeOfImage\fR(\fIimage, widthPtr, heightPtr\fR)
 .sp
 \fBTk_FreeImage\fR(\fIimage\fR)
 .SH ARGUMENTS
 .AS Tk_ImageChangedProc *changeProc
 .AP Tcl_Interp *interp in
 Place to leave error message.
 .AP Tk_Window tkwin in
 Window in which image will be used.
 .AP "CONST char" *name in
 Name of image.
 .AP Tk_ImageChangedProc *changeProc in
 Procedure for Tk to invoke whenever image content or size changes.
 .AP ClientData clientData in
 One-word value for Tk to pass to \fIchangeProc\fR.
 .AP Tk_Image image in
 Token for image instance;  must have been returned by a previous
 call to \fBTk_GetImage\fR.
 .AP int imageX in
 X-coordinate of upper-left corner of region of image to redisplay
 (measured in pixels from the image's upper-left corner).
 .AP int imageY in
 Y-coordinate of upper-left corner of region of image to redisplay
 (measured in pixels from the image's upper-left corner).
 .AP "int" width (in)
 Width of region of image to redisplay.
 .AP "int" height (in)
 Height of region of image to redisplay.
 .AP Drawable drawable in
 Where to display image.  Must either be window specified to
 \fBTk_GetImage\fR or a pixmap compatible with that window.
 .AP int drawableX in
 Where to display image in \fIdrawable\fR: this is the x-coordinate
 in \fIdrawable\fR where x-coordinate \fIimageX\fR of the image
 should be displayed.
 .AP int drawableY in
 Where to display image in \fIdrawable\fR: this is the y-coordinate
 in \fIdrawable\fR where y-coordinate \fIimageY\fR of the image
 should be displayed.
 .AP "int" widthPtr out
 Store width of \fIimage\fR (in pixels) here.
 .AP "int" heightPtr out
 Store height of \fIimage\fR (in pixels) here.
 .BE

 .SH DESCRIPTION
 .PP
 These procedures are invoked by widgets that wish to display images.
 \fBTk_GetImage\fR is invoked by a widget when it first decides to
 display an image.
 \fIname\fR gives the name of the desired image and \fItkwin\fR
 identifies the window where the image will be displayed.
 \fBTk_GetImage\fR looks up the image in the table of existing
 images and returns a token for a new instance of the image.
 If the image doesn't exist then \fBTk_GetImage\fR returns NULL
 and leaves an error message in \fIinterp->result\fR.
 .PP
 When a widget wishes to actually display an image it must
 call \fBTk_RedrawImage\fR, identifying the image (\fIimage\fR),
 a region within the image to redisplay (\fIimageX\fR, \fIimageY\fR,
 \fIwidth\fR, and \fIheight\fR), and a place to display the
 image (\fIdrawable\fR, \fIdrawableX\fR, and \fIdrawableY\fR).
 Tk will then invoke the appropriate image manager, which will
 display the requested portion of the image before returning.
 .PP
 A widget can find out the dimensions of an image by calling
 \fBTk_SizeOfImage\fR:  the width and height will be stored
 in the locations given by \fIwidthPtr\fR and \fIheightPtr\fR,
 respectively.
 .PP
 When a widget is finished with an image (e.g., the widget is
 being deleted or it is going to use a different image instead
 of the current one), it must call \fBTk_FreeImage\fR to
 release the image instance.
 The widget should never again use the image token after passing
 it to \fBTk_FreeImage\fR.
 There must be exactly one call to \fBTk_FreeImage\fR for each
 call to \fBTk_GetImage\fR.
 .PP
 If the contents or size of an image changes, then any widgets
 using the image will need to find out about the changes so that
 they can redisplay themselves.
 The \fIchangeProc\fR and \fIclientData\fR arguments to
 \fBTk_GetImage\fR are used for this purpose.
 \fIchangeProc\fR will be called by Tk whenever a change occurs
 in the image;  it must match the following prototype:
 .CS
 typedef void Tk_ImageChangedProc(
 	ClientData \fIclientData\fR,
 	int \fIx\fR,
 	int \fIy\fR,
 	int \fIwidth\fR,
 	int \fIheight\fR,
 	int \fIimageWidth\fR,
 	int \fIimageHeight\fR);
 .CE
 The \fIclientData\fR argument to \fIchangeProc\fR is the same as the
 \fIclientData\fR argument to \fBTk_GetImage\fR.
 It is usually a pointer to the widget record for the widget or
 some other data structure managed by the widget.
 The arguments \fIx\fR, \fIy\fR, \fIwidth\fR, and \fIheight\fR
 identify a region within the image that must be redisplayed;
 they are specified in pixels measured from the upper-left
 corner of the image.
 The arguments \fIimageWidth\fR and \fIimageHeight\fR give
 the image's (new) size.

 .SH "SEE ALSO"
 Tk_CreateImageType

 .SH KEYWORDS
 images, redisplay
	'\"
	'\" Copyright (c) 1994 The Regents of the University of California.
	'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
	'\"
	'\" See the file "license.terms" for information on usage and redistribution
	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	'\"
	'\" RCS: @(#) $Id: GetImage.3,v 1.5 2002/08/05 04:30:38 dgp Exp $
	'\"
	'\" The definitions below are for supplemental macros used in Tcl/Tk
	'\" manual entries.
	'\"
	'\" .AP type name in/out ?indent?
	'\" Start paragraph describing an argument to a library procedure.
	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	'\" or "in/out" to describe whether procedure reads or modifies arg,
	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	'\" needed; use .AS below instead)
	'\"
	'\" .AS ?type? ?name?
	'\" Give maximum sizes of arguments for setting tab stops. Type and
	'\" name are examples of largest possible arguments that will be passed
	'\" to .AP later. If args are omitted, default tab stops are used.
	'\"
	'\" .BS
	'\" Start box enclosure. From here until next .BE, everything will be
	'\" enclosed in one large box.
	'\"
	'\" .BE
	'\" End of box enclosure.
	'\"
	'\" .CS
	'\" Begin code excerpt.
	'\"
	'\" .CE
	'\" End code excerpt.
	'\"
	'\" .VS ?version? ?br?
	'\" Begin vertical sidebar, for use in marking newly-changed parts
	'\" of man pages. The first argument is ignored and used for recording
	'\" the version when the .VS was added, so that the sidebars can be
	'\" found and removed when they reach a certain age. If another argument
	'\" is present, then a line break is forced before starting the sidebar.
	'\"
	'\" .VE
	'\" End of vertical sidebar.
	'\"
	'\" .DS
	'\" Begin an indented unfilled display.
	'\"
	'\" .DE
	'\" End of indented unfilled display.
	'\"
	'\" .SO
	'\" Start of list of standard options for a Tk widget. The
	'\" options follow on successive lines, in four columns separated
	'\" by tabs.
	'\"
	'\" .SE
	'\" End of list of standard options for a Tk widget.
	'\"
	'\" .OP cmdName dbName dbClass
	'\" Start of description of a specific option. cmdName gives the
	'\" option's name as specified in the class command, dbName gives
	'\" the option's name in the option database, and dbClass gives
	'\" the option's class in the option database.
	'\"
	'\" .UL arg1 arg2
	'\" Print arg1 underlined, then print arg2 normally.
	'\"
	'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
	'\"
	'\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
	.if t .wh -1.3i ^B
	.nr ^l \n(.l
	.ad b
	'\" # Start an argument description
	.de AP
	.ie !"\\$4"" .TP \\$4
	.el \{\
	. ie !"\\$2"" .TP \\n()Cu
	. el .TP 15
	.\}
	.ta \\n()Au \\n()Bu
	.ie !"\\$3"" \{\
	\&\\$1 \\fI\\$2\\fP (\\$3)
	.\".b
	.\}
	.el \{\
	.br
	.ie !"\\$2"" \{\
	\&\\$1 \\fI\\$2\\fP
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	.el \{\
	\&\\fI\\$1\\fP
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	.\}
	..
	'\" # define tabbing values for .AP
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	.nr )A 10n
	.if !"\\$1"" .nr )A \\w'\\$1'u+3n
	.nr )B \\n()Au+15n
	.\"
	.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
	.nr )C \\n()Bu+\\w'(in/out)'u+2n
	..
	.AS Tcl_Interp Tcl_CreateInterp in/out
	'\" # BS - start boxed text
	'\" # ^y = starting y location
	'\" # ^b = 1
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	.\" Draw four-sided box normally, but don't draw top of
	.\" box if the box started on an earlier page.
	.ie !\\n(^b-1 \{\
	\h'-1.5n'\L'\|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
	.\}
	.el \}\
	\h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'\|0u-1.5n\(ul'
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	.\" draw two sides but no top otherwise.
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	.el \h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
	.\}
	.if \\n(^v \{\
	.nr ^x \\n(^tu+1v-\\n(^Yu
	\kx\h'-\\nxu'\h'\|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'\|0u'\c
	.\}
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	'fi
	.ev
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	.de SO
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	.LP
	.nf
	.ta 5.5c 11c
	.ft B
	..
	'\" # SE - end of list of standard options
	.de SE
	.fi
	.ft R
	.LP
	See the \\fBoptions\\fR manual entry for details on the standard options.
	..
	'\" # OP - start of full description for a single option
	.de OP
	.LP
	.nf
	.ta 4c
	Command-Line Name: \\fB\\$1\\fR
	Database Name: \\fB\\$2\\fR
	Database Class: \\fB\\$3\\fR
	.fi
	.IP
	..
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	..
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	.fi
	.RE
	..
	.de UL
	\\$1\l'\|0\(ul'\\$2
	..
	.TH Tk_GetImage 3 4.0 Tk "Tk Library Procedures"
	.BS
	.SH NAME
	Tk_GetImage, Tk_RedrawImage, Tk_SizeOfImage, Tk_FreeImage \- use an image in a widget
	.SH SYNOPSIS
	.nf
	\fB#include <tk.h>\fR
	.sp
	Tk_Image
	\fBTk_GetImage\fR(\fIinterp, tkwin, name, changeProc, clientData\fR)
	.sp
	\fBTk_RedrawImage\fR(\fIimage, imageX, imageY, width, height, drawable, drawableX, drawableY\fR)
	.sp
	\fBTk_SizeOfImage\fR(\fIimage, widthPtr, heightPtr\fR)
	.sp
	\fBTk_FreeImage\fR(\fIimage\fR)
	.SH ARGUMENTS
	.AS Tk_ImageChangedProc *changeProc
	.AP Tcl_Interp *interp in
	Place to leave error message.
	.AP Tk_Window tkwin in
	Window in which image will be used.
	.AP "CONST char" *name in
	Name of image.
	.AP Tk_ImageChangedProc *changeProc in
	Procedure for Tk to invoke whenever image content or size changes.
	.AP ClientData clientData in
	One-word value for Tk to pass to \fIchangeProc\fR.
	.AP Tk_Image image in
	Token for image instance; must have been returned by a previous
	call to \fBTk_GetImage\fR.
	.AP int imageX in
	X-coordinate of upper-left corner of region of image to redisplay
	(measured in pixels from the image's upper-left corner).
	.AP int imageY in
	Y-coordinate of upper-left corner of region of image to redisplay
	(measured in pixels from the image's upper-left corner).
	.AP "int" width (in)
	Width of region of image to redisplay.
	.AP "int" height (in)
	Height of region of image to redisplay.
	.AP Drawable drawable in
	Where to display image. Must either be window specified to
	\fBTk_GetImage\fR or a pixmap compatible with that window.
	.AP int drawableX in
	Where to display image in \fIdrawable\fR: this is the x-coordinate
	in \fIdrawable\fR where x-coordinate \fIimageX\fR of the image
	should be displayed.
	.AP int drawableY in
	Where to display image in \fIdrawable\fR: this is the y-coordinate
	in \fIdrawable\fR where y-coordinate \fIimageY\fR of the image
	should be displayed.
	.AP "int" widthPtr out
	Store width of \fIimage\fR (in pixels) here.
	.AP "int" heightPtr out
	Store height of \fIimage\fR (in pixels) here.
	.BE

	.SH DESCRIPTION
	.PP
	These procedures are invoked by widgets that wish to display images.
	\fBTk_GetImage\fR is invoked by a widget when it first decides to
	display an image.
	\fIname\fR gives the name of the desired image and \fItkwin\fR
	identifies the window where the image will be displayed.
	\fBTk_GetImage\fR looks up the image in the table of existing
	images and returns a token for a new instance of the image.
	If the image doesn't exist then \fBTk_GetImage\fR returns NULL
	and leaves an error message in \fIinterp->result\fR.
	.PP
	When a widget wishes to actually display an image it must
	call \fBTk_RedrawImage\fR, identifying the image (\fIimage\fR),
	a region within the image to redisplay (\fIimageX\fR, \fIimageY\fR,
	\fIwidth\fR, and \fIheight\fR), and a place to display the
	image (\fIdrawable\fR, \fIdrawableX\fR, and \fIdrawableY\fR).
	Tk will then invoke the appropriate image manager, which will
	display the requested portion of the image before returning.
	.PP
	A widget can find out the dimensions of an image by calling
	\fBTk_SizeOfImage\fR: the width and height will be stored
	in the locations given by \fIwidthPtr\fR and \fIheightPtr\fR,
	respectively.
	.PP
	When a widget is finished with an image (e.g., the widget is
	being deleted or it is going to use a different image instead
	of the current one), it must call \fBTk_FreeImage\fR to
	release the image instance.
	The widget should never again use the image token after passing
	it to \fBTk_FreeImage\fR.
	There must be exactly one call to \fBTk_FreeImage\fR for each
	call to \fBTk_GetImage\fR.
	.PP
	If the contents or size of an image changes, then any widgets
	using the image will need to find out about the changes so that
	they can redisplay themselves.
	The \fIchangeProc\fR and \fIclientData\fR arguments to
	\fBTk_GetImage\fR are used for this purpose.
	\fIchangeProc\fR will be called by Tk whenever a change occurs
	in the image; it must match the following prototype:
	.CS
	typedef void Tk_ImageChangedProc(
	ClientData \fIclientData\fR,
	int \fIx\fR,
	int \fIy\fR,
	int \fIwidth\fR,
	int \fIheight\fR,
	int \fIimageWidth\fR,
	int \fIimageHeight\fR);
	.CE
	The \fIclientData\fR argument to \fIchangeProc\fR is the same as the
	\fIclientData\fR argument to \fBTk_GetImage\fR.
	It is usually a pointer to the widget record for the widget or
	some other data structure managed by the widget.
	The arguments \fIx\fR, \fIy\fR, \fIwidth\fR, and \fIheight\fR
	identify a region within the image that must be redisplayed;
	they are specified in pixels measured from the upper-left
	corner of the image.
	The arguments \fIimageWidth\fR and \fIimageHeight\fR give
	the image's (new) size.

	.SH "SEE ALSO"
	Tk_CreateImageType

	.SH KEYWORDS
	images, redisplay