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diff --git a/tcl/doc/CanvTkwin.3 b/tcl/doc/CanvTkwin.3 deleted file mode 100644 index 7a214228330..00000000000 --- a/tcl/doc/CanvTkwin.3 +++ /dev/null @@ -1,161 +0,0 @@ -'\" -'\" 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: @(#) $Id$ -'\" -.so man.macros -.TH Tk_CanvasTkwin 3 4.1 Tk "Tk Library Procedures" -.BS -.SH NAME -Tk_CanvasTkwin, Tk_CanvasGetCoord, Tk_CanvasDrawableCoords, Tk_CanvasSetStippleOrigin, Tk_CanvasWindowCoords, Tk_CanvasEventuallyRedraw, Tk_CanvasTagsOption \- utility procedures for canvas type managers -.SH SYNOPSIS -.nf -\fB#include <tk.h>\fR -.sp -Tk_Window -\fBTk_CanvasTkwin\fR(\fIcanvas\fR) -.sp -int -\fBTk_CanvasGetCoord\fR(\fIinterp, canvas, string, doublePtr\fR) -.sp -\fBTk_CanvasDrawableCoords\fR(\fIcanvas, x, y, drawableXPtr, drawableYPtr\fR) -.sp -\fBTk_CanvasSetStippleOrigin\fR(\fIcanvas, gc\fR) -.sp -\fBTk_CanvasWindowCoords\fR(\fIcanvas, x, y, screenXPtr, screenYPtr\fR) -.sp -\fBTk_CanvasEventuallyRedraw\fR(\fIcanvas, x1, y1, x2, y2\fR) -.sp -Tk_OptionParseProc *\fBTk_CanvasTagsParseProc\fR; -.sp -Tk_OptionPrintProc *\fBTk_CanvasTagsPrintProc\fR; -.SH ARGUMENTS -.AS Tk_ItemType *drawableXPtr -.AP Tk_Canvas canvas in -A token that identifies a canvas widget. -.AP Tcl_Interp *interp in/out -Interpreter to use for error reporting. -.AP "CONST char" *string in -Textual description of a canvas coordinate. -.AP double *doublePtr out -Points to place to store a converted coordinate. -.AP double x in -An x coordinate in the space of the canvas. -.AP double y in -A y coordinate in the space of the canvas. -.AP short *drawableXPtr out -Pointer to a location in which to store an x coordinate in the space -of the drawable currently being used to redisplay the canvas. -.AP short *drawableYPtr out -Pointer to a location in which to store a y coordinate in the space -of the drawable currently being used to redisplay the canvas. -.AP GC gc out -Graphics context to modify. -.AP short *screenXPtr out -Points to a location in which to store the screen coordinate in the -canvas window that corresponds to \fIx\fR. -.AP short *screenYPtr out -Points to a location in which to store the screen coordinate in the -canvas window that corresponds to \fIy\fR. -.AP int x1 in -Left edge of the region that needs redisplay. Only pixels at or to -the right of this coordinate need to be redisplayed. -.AP int y1 in -Top edge of the region that needs redisplay. Only pixels at or below -this coordinate need to be redisplayed. -.AP int x2 in -Right edge of the region that needs redisplay. Only pixels to -the left of this coordinate need to be redisplayed. -.AP int y2 in -Bottom edge of the region that needs redisplay. Only pixels above -this coordinate need to be redisplayed. -.BE - -.SH DESCRIPTION -.PP -These procedures are called by canvas type managers to perform various -utility functions. -.PP -\fBTk_CanvasTkwin\fR returns the Tk_Window associated with a particular -canvas. -.PP -\fBTk_CanvasGetCoord\fR translates a string specification of a -coordinate (such as \fB2p\fR or \fB1.6c\fR) into a double-precision -canvas coordinate. -If \fIstring\fR is a valid coordinate description then \fBTk_CanvasGetCoord\fR -stores the corresponding canvas coordinate at *\fIdoublePtr\fR -and returns TCL_OK. -Otherwise it stores an error message in \fIinterp->result\fR and -returns TCL_ERROR. -.PP -\fBTk_CanvasDrawableCoords\fR is called by type managers during -redisplay to compute where to draw things. -Given \fIx\fR and \fIy\fR coordinates in the space of the -canvas, \fBTk_CanvasDrawableCoords\fR computes the corresponding -pixel in the drawable that is currently being used for redisplay; -it returns those coordinates in *\fIdrawableXPtr\fR and *\fIdrawableYPtr\fR. -This procedure should not be invoked except during redisplay. -.PP -\fBTk_CanvasSetStippleOrigin\fR is also used during redisplay. -It sets the stipple origin in \fIgc\fR so that stipples drawn -with \fIgc\fR in the current offscreen pixmap will line up -with stipples drawn with origin (0,0) in the canvas's actual -window. -\fBTk_CanvasSetStippleOrigin\fR is needed in order to guarantee -that stipple patterns line up properly when the canvas is -redisplayed in small pieces. -Redisplays are carried out in double-buffered fashion where a -piece of the canvas is redrawn in an offscreen pixmap and then -copied back onto the screen. -In this approach the stipple origins in graphics contexts need to -be adjusted during each redisplay to compensate for the position -of the off-screen pixmap relative to the window. -If an item is being drawn with stipples, its type manager typically -calls \fBTk_CanvasSetStippleOrigin\fR just before using \fIgc\fR -to draw something; after it is finished drawing, the type manager -calls \fBXSetTSOrigin\fR to restore the origin in \fIgc\fR back to (0,0) -(the restore is needed because graphics contexts are shared, so -they cannot be modified permanently). -.PP -\fBTk_CanvasWindowCoords\fR is similar to \fBTk_CanvasDrawableCoords\fR -except that it returns coordinates in the canvas's window on the -screen, instead of coordinates in an off-screen pixmap. -.PP -\fBTk_CanvasEventuallyRedraw\fR may be invoked by a type manager -to inform Tk that a portion of a canvas needs to be redrawn. -The \fIx1\fR, \fIy1\fR, \fIx2\fR, and \fIy2\fR arguments -specify the region that needs to be redrawn, in canvas coordinates. -Type managers rarely need to invoke \fBTk_CanvasEventuallyRedraw\fR, -since Tk can normally figure out when an item has changed and make -the redisplay request on its behalf (this happens, for example -whenever Tk calls a \fIconfigureProc\fR or \fIscaleProc\fR). -The only time that a type manager needs to call -\fBTk_CanvasEventuallyRedraw\fR is if an item has changed on its own -without being invoked through one of the procedures in its Tk_ItemType; -this could happen, for example, in an image item if the image is -modified using image commands. -.PP -\fBTk_CanvasTagsParseProc\fR and \fBTk_CanvasTagsPrintProc\fR are -procedures that handle the \fB\-tags\fR option for canvas items. -The code of a canvas type manager won't call these procedures -directly, but will use their addresses to create a \fBTk_CustomOption\fR -structure for the \fB\-tags\fR option. The code typically looks -like this: -.CS -static Tk_CustomOption tagsOption = {Tk_CanvasTagsParseProc, - Tk_CanvasTagsPrintProc, (ClientData) NULL -}; - -static Tk_ConfigSpec configSpecs[] = { - ... - {TK_CONFIG_CUSTOM, "\-tags", (char *) NULL, (char *) NULL, - (char *) NULL, 0, TK_CONFIG_NULL_OK, &tagsOption}, - ... -}; -.CE - -.SH KEYWORDS -canvas, focus, item type, redisplay, selection, type manager |