[OpenSPARC-T2-SAM] / sam-t2 / devtools / v9 / man / man3 / Tk_SizeOfImage.3

'\"
'\" 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?
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'\"	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.
'\"
'\" .OP cmdName dbName dbClass
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'\"	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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.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
Commit	Line	Data
920dae64 AT	1	'\"
	2	'\" Copyright (c) 1994 The Regents of the University of California.
	3	'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
	4	'\"
	5	'\" See the file "license.terms" for information on usage and redistribution
	6	'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
	7	'\"
	8	'\" RCS: @(#) $Id: GetImage.3,v 1.5 2002/08/05 04:30:38 dgp Exp $
	9	'\"
	10	'\" The definitions below are for supplemental macros used in Tcl/Tk
	11	'\" manual entries.
	12	'\"
	13	'\" .AP type name in/out ?indent?
	14	'\" Start paragraph describing an argument to a library procedure.
	15	'\" type is type of argument (int, etc.), in/out is either "in", "out",
	16	'\" or "in/out" to describe whether procedure reads or modifies arg,
	17	'\" and indent is equivalent to second arg of .IP (shouldn't ever be
	18	'\" needed; use .AS below instead)
	19	'\"
	20	'\" .AS ?type? ?name?
	21	'\" Give maximum sizes of arguments for setting tab stops. Type and
	22	'\" name are examples of largest possible arguments that will be passed
	23	'\" to .AP later. If args are omitted, default tab stops are used.
	24	'\"
	25	'\" .BS
	26	'\" Start box enclosure. From here until next .BE, everything will be
	27	'\" enclosed in one large box.
	28	'\"
	29	'\" .BE
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	31	'\"
	32	'\" .CS
	33	'\" Begin code excerpt.
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	37	'\"
	38	'\" .VS ?version? ?br?
	39	'\" Begin vertical sidebar, for use in marking newly-changed parts
	40	'\" of man pages. The first argument is ignored and used for recording
	41	'\" the version when the .VS was added, so that the sidebars can be
	42	'\" found and removed when they reach a certain age. If another argument
	43	'\" is present, then a line break is forced before starting the sidebar.
	44	'\"
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	55	'\" Start of list of standard options for a Tk widget. The
	56	'\" options follow on successive lines, in four columns separated
	57	'\" by tabs.
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	60	'\" End of list of standard options for a Tk widget.
	61	'\"
	62	'\" .OP cmdName dbName dbClass
	63	'\" Start of description of a specific option. cmdName gives the
	64	'\" option's name as specified in the class command, dbName gives
65	'\" the option's name in the option database, and dbClass gives
66	'\" the option's class in the option database.
67	'\"
68	'\" .UL arg1 arg2
69	'\" Print arg1 underlined, then print arg2 normally.
70	'\"
71	'\" RCS: @(#) $Id: man.macros,v 1.4 2000/08/25 06:18:32 ericm Exp $
72	'\"
73	'\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
74	.if t .wh -1.3i ^B
75	.nr ^l \n(.l
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78	.de AP
79	.ie !"\\$4"" .TP \\$4
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81	. ie !"\\$2"" .TP \\n()Cu
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108	.AS Tcl_Interp Tcl_CreateInterp in/out
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177	.el \h'-1.5n'\L'\|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'\|0u'\c
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207	.de SO
208	.SH "STANDARD OPTIONS"
209	.LP
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211	.ta 5.5c 11c
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213	..
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219	See the \\fBoptions\\fR manual entry for details on the standard options.
220	..
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222	.de OP
223	.LP
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226	Command-Line Name: \\fB\\$1\\fR
227	Database Name: \\fB\\$2\\fR
228	Database Class: \\fB\\$3\\fR
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243	.de UL
244	\\$1\l'\|0\(ul'\\$2
245	..
246	.TH Tk_GetImage 3 4.0 Tk "Tk Library Procedures"
247	.BS
248	.SH NAME
249	Tk_GetImage, Tk_RedrawImage, Tk_SizeOfImage, Tk_FreeImage \- use an image in a widget
250	.SH SYNOPSIS
251	.nf
252	\fB#include <tk.h>\fR
253	.sp
254	Tk_Image
255	\fBTk_GetImage\fR(\fIinterp, tkwin, name, changeProc, clientData\fR)
256	.sp
257	\fBTk_RedrawImage\fR(\fIimage, imageX, imageY, width, height, drawable, drawableX, drawableY\fR)
258	.sp
259	\fBTk_SizeOfImage\fR(\fIimage, widthPtr, heightPtr\fR)
260	.sp
261	\fBTk_FreeImage\fR(\fIimage\fR)
262	.SH ARGUMENTS
263	.AS Tk_ImageChangedProc *changeProc
264	.AP Tcl_Interp *interp in
265	Place to leave error message.
266	.AP Tk_Window tkwin in
267	Window in which image will be used.
268	.AP "CONST char" *name in
269	Name of image.
270	.AP Tk_ImageChangedProc *changeProc in
271	Procedure for Tk to invoke whenever image content or size changes.
272	.AP ClientData clientData in
273	One-word value for Tk to pass to \fIchangeProc\fR.
274	.AP Tk_Image image in
275	Token for image instance; must have been returned by a previous
276	call to \fBTk_GetImage\fR.
277	.AP int imageX in
278	X-coordinate of upper-left corner of region of image to redisplay
279	(measured in pixels from the image's upper-left corner).
280	.AP int imageY in
281	Y-coordinate of upper-left corner of region of image to redisplay
282	(measured in pixels from the image's upper-left corner).
283	.AP "int" width (in)
284	Width of region of image to redisplay.
285	.AP "int" height (in)
286	Height of region of image to redisplay.
287	.AP Drawable drawable in
288	Where to display image. Must either be window specified to
289	\fBTk_GetImage\fR or a pixmap compatible with that window.
290	.AP int drawableX in
291	Where to display image in \fIdrawable\fR: this is the x-coordinate
292	in \fIdrawable\fR where x-coordinate \fIimageX\fR of the image
293	should be displayed.
294	.AP int drawableY in
295	Where to display image in \fIdrawable\fR: this is the y-coordinate
296	in \fIdrawable\fR where y-coordinate \fIimageY\fR of the image
297	should be displayed.
298	.AP "int" widthPtr out
299	Store width of \fIimage\fR (in pixels) here.
300	.AP "int" heightPtr out
301	Store height of \fIimage\fR (in pixels) here.
302	.BE
303
304	.SH DESCRIPTION
305	.PP
306	These procedures are invoked by widgets that wish to display images.
307	\fBTk_GetImage\fR is invoked by a widget when it first decides to
308	display an image.
309	\fIname\fR gives the name of the desired image and \fItkwin\fR
310	identifies the window where the image will be displayed.
311	\fBTk_GetImage\fR looks up the image in the table of existing
312	images and returns a token for a new instance of the image.
313	If the image doesn't exist then \fBTk_GetImage\fR returns NULL
314	and leaves an error message in \fIinterp->result\fR.
315	.PP
316	When a widget wishes to actually display an image it must
317	call \fBTk_RedrawImage\fR, identifying the image (\fIimage\fR),
318	a region within the image to redisplay (\fIimageX\fR, \fIimageY\fR,
319	\fIwidth\fR, and \fIheight\fR), and a place to display the
320	image (\fIdrawable\fR, \fIdrawableX\fR, and \fIdrawableY\fR).
321	Tk will then invoke the appropriate image manager, which will
322	display the requested portion of the image before returning.
323	.PP
324	A widget can find out the dimensions of an image by calling
325	\fBTk_SizeOfImage\fR: the width and height will be stored
326	in the locations given by \fIwidthPtr\fR and \fIheightPtr\fR,
327	respectively.
328	.PP
329	When a widget is finished with an image (e.g., the widget is
330	being deleted or it is going to use a different image instead
331	of the current one), it must call \fBTk_FreeImage\fR to
332	release the image instance.
333	The widget should never again use the image token after passing
334	it to \fBTk_FreeImage\fR.
335	There must be exactly one call to \fBTk_FreeImage\fR for each
336	call to \fBTk_GetImage\fR.
337	.PP
338	If the contents or size of an image changes, then any widgets
339	using the image will need to find out about the changes so that
340	they can redisplay themselves.
341	The \fIchangeProc\fR and \fIclientData\fR arguments to
342	\fBTk_GetImage\fR are used for this purpose.
343	\fIchangeProc\fR will be called by Tk whenever a change occurs
344	in the image; it must match the following prototype:
345	.CS
346	typedef void Tk_ImageChangedProc(
347	ClientData \fIclientData\fR,
348	int \fIx\fR,
349	int \fIy\fR,
350	int \fIwidth\fR,
351	int \fIheight\fR,
352	int \fIimageWidth\fR,
353	int \fIimageHeight\fR);
354	.CE
355	The \fIclientData\fR argument to \fIchangeProc\fR is the same as the
356	\fIclientData\fR argument to \fBTk_GetImage\fR.
357	It is usually a pointer to the widget record for the widget or
358	some other data structure managed by the widget.
359	The arguments \fIx\fR, \fIy\fR, \fIwidth\fR, and \fIheight\fR
360	identify a region within the image that must be redisplayed;
361	they are specified in pixels measured from the upper-left
362	corner of the image.
363	The arguments \fIimageWidth\fR and \fIimageHeight\fR give
364	the image's (new) size.
365
366	.SH "SEE ALSO"
367	Tk_CreateImageType
368
369	.SH KEYWORDS
370	images, redisplay