tkcanvtext.c

linux系统下的音频通信

/* 
 * tkCanvText.c --
 *
 *	This file implements text items for canvas widgets.
 *
 * Copyright (c) 1991-1994 The Regents of the University of California.
 * Copyright (c) 1994-1995 Sun Microsystems, Inc.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * SCCS: @(#) tkCanvText.c 1.68 97/10/09 17:44:53
 */

#include <stdio.h>
#include "tkInt.h"
#include "tkCanvas.h"
#include "tkPort.h"
#include "default.h"

/*
 * The structure below defines the record for each text item.
 */

typedef struct TextItem  {
    Tk_Item header;		/* Generic stuff that's the same for all
				 * types.  MUST BE FIRST IN STRUCTURE. */
    Tk_CanvasTextInfo *textInfoPtr;
				/* Pointer to a structure containing
				 * information about the selection and
				 * insertion cursor.  The structure is owned
				 * by (and shared with) the generic canvas
				 * code. */
    /*
     * Fields that are set by widget commands other than "configure".
     */
     
    double x, y;		/* Positioning point for text. */
    int insertPos;		/* Insertion cursor is displayed just to left
				 * of character with this index. */

    /*
     * Configuration settings that are updated by Tk_ConfigureWidget.
     */

    Tk_Anchor anchor;		/* Where to anchor text relative to (x,y). */
    XColor *color;		/* Color for text. */
    Tk_Font tkfont;		/* Font for drawing text. */
    Tk_Justify justify;		/* Justification mode for text. */
    Pixmap stipple;		/* Stipple bitmap for text, or None. */
    char *text;			/* Text for item (malloc-ed). */
    int width;			/* Width of lines for word-wrap, pixels.
				 * Zero means no word-wrap. */

    /*
     * Fields whose values are derived from the current values of the
     * configuration settings above.
     */

    int numChars;		/* Number of non-NULL characters in text. */
    Tk_TextLayout textLayout;	/* Cached text layout information. */
    int leftEdge;		/* Pixel location of the left edge of the
				 * text item; where the left border of the
				 * text layout is drawn. */
    int rightEdge;		/* Pixel just to right of right edge of
				 * area of text item.  Used for selecting up
				 * to end of line. */
    GC gc;			/* Graphics context for drawing text. */
    GC selTextGC;		/* Graphics context for selected text. */
    GC cursorOffGC;		/* If not None, this gives a graphics context
				 * to use to draw the insertion cursor when
				 * it's off.  Used if the selection and
				 * insertion cursor colors are the same.  */
} TextItem;

/*
 * Information used for parsing configuration specs:
 */

static Tk_CustomOption tagsOption = {Tk_CanvasTagsParseProc,
    Tk_CanvasTagsPrintProc, (ClientData) NULL
};

static Tk_ConfigSpec configSpecs[] = {
    {TK_CONFIG_ANCHOR, "-anchor", (char *) NULL, (char *) NULL,
	"center", Tk_Offset(TextItem, anchor),
	TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_COLOR, "-fill", (char *) NULL, (char *) NULL,
	"black", Tk_Offset(TextItem, color), 0},
    {TK_CONFIG_FONT, "-font", (char *) NULL, (char *) NULL,
	DEF_CANVTEXT_FONT, Tk_Offset(TextItem, tkfont), 0},
    {TK_CONFIG_JUSTIFY, "-justify", (char *) NULL, (char *) NULL,
	"left", Tk_Offset(TextItem, justify),
	TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_BITMAP, "-stipple", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(TextItem, stipple), TK_CONFIG_NULL_OK},
    {TK_CONFIG_CUSTOM, "-tags", (char *) NULL, (char *) NULL,
	(char *) NULL, 0, TK_CONFIG_NULL_OK, &tagsOption},
    {TK_CONFIG_STRING, "-text", (char *) NULL, (char *) NULL,
	"", Tk_Offset(TextItem, text), 0},
    {TK_CONFIG_PIXELS, "-width", (char *) NULL, (char *) NULL,
	"0", Tk_Offset(TextItem, width), TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
	(char *) NULL, 0, 0}
};

/*
 * Prototypes for procedures defined in this file:
 */

static void		ComputeTextBbox _ANSI_ARGS_((Tk_Canvas canvas,
			    TextItem *textPtr));
static int		ConfigureText _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr, int argc,
			    char **argv, int flags));
static int		CreateText _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, struct Tk_Item *itemPtr,
			    int argc, char **argv));
static void		DeleteText _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, Display *display));
static void		DisplayCanvText _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, Display *display, Drawable dst,
			    int x, int y, int width, int height));
static int		GetSelText _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, int offset, char *buffer,
			    int maxBytes));
static int		GetTextIndex _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr,
			    char *indexString, int *indexPtr));
static void		ScaleText _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double originX, double originY,
			    double scaleX, double scaleY));
static void		SetTextCursor _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, int index));
static int		TextCoords _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr,
			    int argc, char **argv));
static void		TextDeleteChars _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, int first, int last));
static void		TextInsert _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, int beforeThis, char *string));
static int		TextToArea _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double *rectPtr));
static double		TextToPoint _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double *pointPtr));
static int		TextToPostscript _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr, int prepass));
static void		TranslateText _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double deltaX, double deltaY));

/*
 * The structures below defines the rectangle and oval item types
 * by means of procedures that can be invoked by generic item code.
 */

Tk_ItemType tkTextType = {
    "text",				/* name */
    sizeof(TextItem),			/* itemSize */
    CreateText,				/* createProc */
    configSpecs,			/* configSpecs */
    ConfigureText,			/* configureProc */
    TextCoords,				/* coordProc */
    DeleteText,				/* deleteProc */
    DisplayCanvText,			/* displayProc */
    0,					/* alwaysRedraw */
    TextToPoint,			/* pointProc */
    TextToArea,				/* areaProc */
    TextToPostscript,			/* postscriptProc */
    ScaleText,				/* scaleProc */
    TranslateText,			/* translateProc */
    GetTextIndex,			/* indexProc */
    SetTextCursor,			/* icursorProc */
    GetSelText,				/* selectionProc */
    TextInsert,				/* insertProc */
    TextDeleteChars,			/* dTextProc */
    (Tk_ItemType *) NULL		/* nextPtr */
};

/*
 *--------------------------------------------------------------
 *
 * CreateText --
 *
 *	This procedure is invoked to create a new text item
 *	in a canvas.
 *
 * Results:
 *	A standard Tcl return value.  If an error occurred in
 *	creating the item then an error message is left in
 *	interp->result;  in this case itemPtr is left uninitialized
 *	so it can be safely freed by the caller.
 *
 * Side effects:
 *	A new text item is created.
 *
 *--------------------------------------------------------------
 */

static int
CreateText(interp, canvas, itemPtr, argc, argv)
    Tcl_Interp *interp;			/* Interpreter for error reporting. */
    Tk_Canvas canvas;			/* Canvas to hold new item. */
    Tk_Item *itemPtr;			/* Record to hold new item;  header
					 * has been initialized by caller. */
    int argc;				/* Number of arguments in argv. */
    char **argv;			/* Arguments describing rectangle. */
{
    TextItem *textPtr = (TextItem *) itemPtr;

    if (argc < 2) {
	Tcl_AppendResult(interp, "wrong # args: should be \"",
		Tk_PathName(Tk_CanvasTkwin(canvas)), " create ",
		itemPtr->typePtr->name, " x y ?options?\"", (char *) NULL);
	return TCL_ERROR;
    }

    /*
     * Carry out initialization that is needed in order to clean
     * up after errors during the the remainder of this procedure.
     */

    textPtr->textInfoPtr = Tk_CanvasGetTextInfo(canvas);

    textPtr->insertPos	= 0;

    textPtr->anchor	= TK_ANCHOR_CENTER;
    textPtr->color	= NULL;
    textPtr->tkfont	= NULL;
    textPtr->justify	= TK_JUSTIFY_LEFT;
    textPtr->stipple	= None;
    textPtr->text	= NULL;
    textPtr->width	= 0;

    textPtr->numChars	= 0;
    textPtr->textLayout = NULL;
    textPtr->leftEdge	= 0;
    textPtr->rightEdge	= 0;
    textPtr->gc		= None;
    textPtr->selTextGC	= None;
    textPtr->cursorOffGC = None;

    /*
     * Process the arguments to fill in the item record.
     */

    if ((Tk_CanvasGetCoord(interp, canvas, argv[0], &textPtr->x) != TCL_OK)
	    || (Tk_CanvasGetCoord(interp, canvas, argv[1], &textPtr->y)
		!= TCL_OK)) {
	return TCL_ERROR;
    }

    if (ConfigureText(interp, canvas, itemPtr, argc-2, argv+2, 0) != TCL_OK) {
	DeleteText(canvas, itemPtr, Tk_Display(Tk_CanvasTkwin(canvas)));
	return TCL_ERROR;
    }
    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * TextCoords --
 *
 *	This procedure is invoked to process the "coords" widget
 *	command on text items.  See the user documentation for
 *	details on what it does.
 *
 * Results:
 *	Returns TCL_OK or TCL_ERROR, and sets interp->result.
 *
 * Side effects:
 *	The coordinates for the given item may be changed.
 *
 *--------------------------------------------------------------
 */

static int
TextCoords(interp, canvas, itemPtr, argc, argv)
    Tcl_Interp *interp;			/* Used for error reporting. */
    Tk_Canvas canvas;			/* Canvas containing item. */
    Tk_Item *itemPtr;			/* Item whose coordinates are to be
					 * read or modified. */
    int argc;				/* Number of coordinates supplied in
					 * argv. */
    char **argv;			/* Array of coordinates: x1, y1,
					 * x2, y2, ... */
{
    TextItem *textPtr = (TextItem *) itemPtr;
    char x[TCL_DOUBLE_SPACE], y[TCL_DOUBLE_SPACE];

    if (argc == 0) {
	Tcl_PrintDouble(interp, textPtr->x, x);
	Tcl_PrintDouble(interp, textPtr->y, y);
	Tcl_AppendResult(interp, x, " ", y, (char *) NULL);
    } else if (argc == 2) {
	if ((Tk_CanvasGetCoord(interp, canvas, argv[0], &textPtr->x) != TCL_OK)
		|| (Tk_CanvasGetCoord(interp, canvas, argv[1],
		    &textPtr->y) != TCL_OK)) {
	    return TCL_ERROR;
	}
	ComputeTextBbox(canvas, textPtr);
    } else {
	sprintf(interp->result,
		"wrong # coordinates: expected 0 or 2, got %d", argc);
	return TCL_ERROR;
    }
    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * ConfigureText --
 *
 *	This procedure is invoked to configure various aspects
 *	of a text item, such as its border and background colors.
 *
 * Results:
 *	A standard Tcl result code.  If an error occurs, then
 *	an error message is left in interp->result.
 *
 * Side effects:
 *	Configuration information, such as colors and stipple
 *	patterns, may be set for itemPtr.
 *
 *--------------------------------------------------------------
 */

static int
ConfigureText(interp, canvas, itemPtr, argc, argv, flags)
    Tcl_Interp *interp;		/* Interpreter for error reporting. */
    Tk_Canvas canvas;		/* Canvas containing itemPtr. */
    Tk_Item *itemPtr;		/* Rectangle item to reconfigure. */
    int argc;			/* Number of elements in argv.  */
    char **argv;		/* Arguments describing things to configure. */
    int flags;			/* Flags to pass to Tk_ConfigureWidget. */
{
    TextItem *textPtr = (TextItem *) itemPtr;
    XGCValues gcValues;
    GC newGC, newSelGC;
    unsigned long mask;
    Tk_Window tkwin;
    Tk_CanvasTextInfo *textInfoPtr = textPtr->textInfoPtr;
    XColor *selBgColorPtr;

    tkwin = Tk_CanvasTkwin(canvas);
    if (Tk_ConfigureWidget(interp, tkwin, configSpecs, argc, argv,
	    (char *) textPtr, flags) != TCL_OK) {
	return TCL_ERROR;
    }

    /*
     * A few of the options require additional processing, such as
     * graphics contexts.
     */

    newGC = newSelGC = None;
    if ((textPtr->color != NULL) && (textPtr->tkfont != NULL)) {
	gcValues.foreground = textPtr->color->pixel;
	gcValues.font = Tk_FontId(textPtr->tkfont);
	mask = GCForeground|GCFont;
	if (textPtr->stipple != None) {
	    gcValues.stipple = textPtr->stipple;
	    gcValues.fill_style = FillStippled;
	    mask |= GCForeground|GCStipple|GCFillStyle;
	}
	newGC = Tk_GetGC(tkwin, mask, &gcValues);
	gcValues.foreground = textInfoPtr->selFgColorPtr->pixel;
	newSelGC = Tk_GetGC(tkwin, mask, &gcValues);
    }
    if (textPtr->gc != None) {
	Tk_FreeGC(Tk_Display(tkwin), textPtr->gc);
    }
    textPtr->gc = newGC;
    if (textPtr->selTextGC != None) {
	Tk_FreeGC(Tk_Display(tkwin), textPtr->selTextGC);
    }
    textPtr->selTextGC = newSelGC;

    selBgColorPtr = Tk_3DBorderColor(textInfoPtr->selBorder);
    if (Tk_3DBorderColor(textInfoPtr->insertBorder)->pixel
	    == selBgColorPtr->pixel) {
	if (selBgColorPtr->pixel == BlackPixelOfScreen(Tk_Screen(tkwin))) {
	    gcValues.foreground = WhitePixelOfScreen(Tk_Screen(tkwin));
	} else {
	    gcValues.foreground = BlackPixelOfScreen(Tk_Screen(tkwin));
	}
	newGC = Tk_GetGC(tkwin, GCForeground, &gcValues);
    } else {
	newGC = None;
    }
    if (textPtr->cursorOffGC != None) {
	Tk_FreeGC(Tk_Display(tkwin), textPtr->cursorOffGC);
    }
    textPtr->cursorOffGC = newGC;


    /*
     * If the text was changed, move the selection and insertion indices
     * to keep them inside the item.
     */

    textPtr->numChars = strlen(textPtr->text);
    if (textInfoPtr->selItemPtr == itemPtr) {
	if (textInfoPtr->selectFirst >= textPtr->numChars) {
	    textInfoPtr->selItemPtr = NULL;
	} else {
	    if (textInfoPtr->selectLast >= textPtr->numChars) {
		textInfoPtr->selectLast = textPtr->numChars-1;
	    }
	    if ((textInfoPtr->anchorItemPtr == itemPtr)
		    && (textInfoPtr->selectAnchor >= textPtr->numChars)) {
		textInfoPtr->selectAnchor = textPtr->numChars-1;
	    }
	}
    }
    if (textPtr->insertPos >= textPtr->numChars) {
	textPtr->insertPos = textPtr->numChars;
    }

    ComputeTextBbox(canvas, textPtr);
    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * DeleteText --
 *
 *	This procedure is called to clean up the data structure
 *	associated with a text item.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Resources associated with itemPtr are released.
 *