1/*
2 * tkCanvLine.c --
3 *
4 *	This file implements line items for canvas widgets.
5 *
6 * Copyright (c) 1991-1994 The Regents of the University of California.
7 * Copyright (c) 1994-1997 Sun Microsystems, Inc.
8 * Copyright (c) 1998-1999 by Scriptics Corporation.
9 *
10 * See the file "license.terms" for information on usage and redistribution of
11 * this file, and for a DISCLAIMER OF ALL WARRANTIES.
12 *
13 * RCS: @(#) $Id$
14 */
15
16#include <stdio.h>
17#include "tkInt.h"
18#include "tkCanvas.h"
19
20/*
21 * The structure below defines the record for each line item.
22 */
23
24typedef enum {
25    ARROWS_NONE, ARROWS_FIRST, ARROWS_LAST, ARROWS_BOTH
26} Arrows;
27
28typedef struct LineItem  {
29    Tk_Item header;		/* Generic stuff that's the same for all
30				 * types. MUST BE FIRST IN STRUCTURE. */
31    Tk_Outline outline;		/* Outline structure */
32    Tk_Canvas canvas;		/* Canvas containing item. Needed for parsing
33				 * arrow shapes. */
34    int numPoints;		/* Number of points in line (always >= 0). */
35    double *coordPtr;		/* Pointer to malloc-ed array containing x-
36				 * and y-coords of all points in line.
37				 * X-coords are even-valued indices, y-coords
38				 * are corresponding odd-valued indices. If
39				 * the line has arrowheads then the first and
40				 * last points have been adjusted to refer to
41				 * the necks of the arrowheads rather than
42				 * their tips. The actual endpoints are stored
43				 * in the *firstArrowPtr and *lastArrowPtr, if
44				 * they exist. */
45    int capStyle;		/* Cap style for line. */
46    int joinStyle;		/* Join style for line. */
47    GC arrowGC;			/* Graphics context for drawing arrowheads. */
48    Arrows arrow;		/* Indicates whether or not to draw arrowheads:
49				 * "none", "first", "last", or "both". */
50    float arrowShapeA;		/* Distance from tip of arrowhead to center. */
51    float arrowShapeB;		/* Distance from tip of arrowhead to trailing
52				 * point, measured along shaft. */
53    float arrowShapeC;		/* Distance of trailing points from outside
54				 * edge of shaft. */
55    double *firstArrowPtr;	/* Points to array of PTS_IN_ARROW points
56				 * describing polygon for arrowhead at first
57				 * point in line. First point of arrowhead is
58				 * tip. Malloc'ed. NULL means no arrowhead at
59				 * first point. */
60    double *lastArrowPtr;	/* Points to polygon for arrowhead at last
61				 * point in line (PTS_IN_ARROW points, first
62				 * of which is tip). Malloc'ed. NULL means no
63				 * arrowhead at last point. */
64    Tk_SmoothMethod *smooth;	/* Non-zero means draw line smoothed (i.e.
65				 * with Bezier splines). */
66    int splineSteps;		/* Number of steps in each spline segment. */
67} LineItem;
68
69/*
70 * Number of points in an arrowHead:
71 */
72
73#define PTS_IN_ARROW 6
74
75/*
76 * Prototypes for functions defined in this file:
77 */
78
79static int		ArrowheadPostscript(Tcl_Interp *interp,
80			    Tk_Canvas canvas, LineItem *linePtr,
81			    double *arrowPtr);
82static void		ComputeLineBbox(Tk_Canvas canvas, LineItem *linePtr);
83static int		ConfigureLine(Tcl_Interp *interp,
84			    Tk_Canvas canvas, Tk_Item *itemPtr, int objc,
85			    Tcl_Obj *CONST objv[], int flags);
86static int		ConfigureArrows(Tk_Canvas canvas, LineItem *linePtr);
87static int		CreateLine(Tcl_Interp *interp,
88			    Tk_Canvas canvas, struct Tk_Item *itemPtr,
89			    int objc, Tcl_Obj *CONST objv[]);
90static void		DeleteLine(Tk_Canvas canvas,
91			    Tk_Item *itemPtr, Display *display);
92static void		DisplayLine(Tk_Canvas canvas,
93			    Tk_Item *itemPtr, Display *display, Drawable dst,
94			    int x, int y, int width, int height);
95static int		GetLineIndex(Tcl_Interp *interp,
96			    Tk_Canvas canvas, Tk_Item *itemPtr,
97			    Tcl_Obj *obj, int *indexPtr);
98static int		LineCoords(Tcl_Interp *interp,
99			    Tk_Canvas canvas, Tk_Item *itemPtr,
100			    int objc, Tcl_Obj *CONST objv[]);
101static void		LineDeleteCoords(Tk_Canvas canvas,
102			    Tk_Item *itemPtr, int first, int last);
103static void		LineInsert(Tk_Canvas canvas,
104			    Tk_Item *itemPtr, int beforeThis, Tcl_Obj *obj);
105static int		LineToArea(Tk_Canvas canvas,
106			    Tk_Item *itemPtr, double *rectPtr);
107static double		LineToPoint(Tk_Canvas canvas,
108			    Tk_Item *itemPtr, double *coordPtr);
109static int		LineToPostscript(Tcl_Interp *interp,
110			    Tk_Canvas canvas, Tk_Item *itemPtr, int prepass);
111static int		ArrowParseProc(ClientData clientData,
112			    Tcl_Interp *interp, Tk_Window tkwin,
113			    CONST char *value, char *recordPtr, int offset);
114static char *		ArrowPrintProc(ClientData clientData,
115			    Tk_Window tkwin, char *recordPtr, int offset,
116			    Tcl_FreeProc **freeProcPtr);
117static int		ParseArrowShape(ClientData clientData,
118			    Tcl_Interp *interp, Tk_Window tkwin,
119			    CONST char *value, char *recordPtr, int offset);
120static char *		PrintArrowShape(ClientData clientData,
121			    Tk_Window tkwin, char *recordPtr, int offset,
122			    Tcl_FreeProc **freeProcPtr);
123static void		ScaleLine(Tk_Canvas canvas,
124			    Tk_Item *itemPtr, double originX, double originY,
125			    double scaleX, double scaleY);
126static void		TranslateLine(Tk_Canvas canvas,
127			    Tk_Item *itemPtr, double deltaX, double deltaY);
128
129/*
130 * Information used for parsing configuration specs. If you change any of the
131 * default strings, be sure to change the corresponding default values in
132 * CreateLine.
133 */
134
135static Tk_CustomOption arrowShapeOption = {
136    (Tk_OptionParseProc *) ParseArrowShape,
137    PrintArrowShape, (ClientData) NULL
138};
139static Tk_CustomOption arrowOption = {
140    (Tk_OptionParseProc *) ArrowParseProc,
141    ArrowPrintProc, (ClientData) NULL
142};
143static Tk_CustomOption smoothOption = {
144    (Tk_OptionParseProc *) TkSmoothParseProc,
145    TkSmoothPrintProc, (ClientData) NULL
146};
147static Tk_CustomOption stateOption = {
148    (Tk_OptionParseProc *) TkStateParseProc,
149    TkStatePrintProc, (ClientData) 2
150};
151static Tk_CustomOption tagsOption = {
152    (Tk_OptionParseProc *) Tk_CanvasTagsParseProc,
153    Tk_CanvasTagsPrintProc, (ClientData) NULL
154};
155static Tk_CustomOption dashOption = {
156    (Tk_OptionParseProc *) TkCanvasDashParseProc,
157    TkCanvasDashPrintProc, (ClientData) NULL
158};
159static Tk_CustomOption offsetOption = {
160    (Tk_OptionParseProc *) TkOffsetParseProc,
161    TkOffsetPrintProc,
162    (ClientData) (TK_OFFSET_RELATIVE|TK_OFFSET_INDEX)
163};
164static Tk_CustomOption pixelOption = {
165    (Tk_OptionParseProc *) TkPixelParseProc,
166    TkPixelPrintProc, (ClientData) NULL
167};
168
169static Tk_ConfigSpec configSpecs[] = {
170    {TK_CONFIG_CUSTOM, "-activedash", NULL, NULL,
171	NULL, Tk_Offset(LineItem, outline.activeDash),
172	TK_CONFIG_NULL_OK, &dashOption},
173    {TK_CONFIG_COLOR, "-activefill", NULL, NULL,
174	NULL, Tk_Offset(LineItem, outline.activeColor), TK_CONFIG_NULL_OK},
175    {TK_CONFIG_BITMAP, "-activestipple", NULL, NULL,
176	NULL, Tk_Offset(LineItem, outline.activeStipple), TK_CONFIG_NULL_OK},
177    {TK_CONFIG_CUSTOM, "-activewidth", NULL, NULL,
178	"0.0", Tk_Offset(LineItem, outline.activeWidth),
179	TK_CONFIG_DONT_SET_DEFAULT, &pixelOption},
180    {TK_CONFIG_CUSTOM, "-arrow", NULL, NULL,
181	"none", Tk_Offset(LineItem, arrow), TK_CONFIG_DONT_SET_DEFAULT, &arrowOption},
182    {TK_CONFIG_CUSTOM, "-arrowshape", NULL, NULL,
183	"8 10 3", Tk_Offset(LineItem, arrowShapeA),
184	TK_CONFIG_DONT_SET_DEFAULT, &arrowShapeOption},
185    {TK_CONFIG_CAP_STYLE, "-capstyle", NULL, NULL,
186	"butt", Tk_Offset(LineItem, capStyle), TK_CONFIG_DONT_SET_DEFAULT},
187    {TK_CONFIG_COLOR, "-fill", NULL, NULL,
188	"black", Tk_Offset(LineItem, outline.color), TK_CONFIG_NULL_OK},
189    {TK_CONFIG_CUSTOM, "-dash", NULL, NULL,
190	NULL, Tk_Offset(LineItem, outline.dash),
191	TK_CONFIG_NULL_OK, &dashOption},
192    {TK_CONFIG_PIXELS, "-dashoffset", NULL, NULL,
193	"0", Tk_Offset(LineItem, outline.offset), TK_CONFIG_DONT_SET_DEFAULT},
194    {TK_CONFIG_CUSTOM, "-disableddash", NULL, NULL,
195	NULL, Tk_Offset(LineItem, outline.disabledDash),
196	TK_CONFIG_NULL_OK, &dashOption},
197    {TK_CONFIG_COLOR, "-disabledfill", NULL, NULL,
198	NULL, Tk_Offset(LineItem, outline.disabledColor), TK_CONFIG_NULL_OK},
199    {TK_CONFIG_BITMAP, "-disabledstipple", NULL, NULL,
200	NULL, Tk_Offset(LineItem, outline.disabledStipple), TK_CONFIG_NULL_OK},
201    {TK_CONFIG_CUSTOM, "-disabledwidth", NULL, NULL,
202	"0.0", Tk_Offset(LineItem, outline.disabledWidth),
203	TK_CONFIG_DONT_SET_DEFAULT, &pixelOption},
204    {TK_CONFIG_JOIN_STYLE, "-joinstyle", NULL, NULL,
205	"round", Tk_Offset(LineItem, joinStyle), TK_CONFIG_DONT_SET_DEFAULT},
206    {TK_CONFIG_CUSTOM, "-offset", NULL, NULL,
207	"0,0", Tk_Offset(LineItem, outline.tsoffset),
208	TK_CONFIG_DONT_SET_DEFAULT, &offsetOption},
209    {TK_CONFIG_CUSTOM, "-smooth", NULL, NULL,
210	"0", Tk_Offset(LineItem, smooth),
211	TK_CONFIG_DONT_SET_DEFAULT, &smoothOption},
212    {TK_CONFIG_INT, "-splinesteps", NULL, NULL,
213	"12", Tk_Offset(LineItem, splineSteps), TK_CONFIG_DONT_SET_DEFAULT},
214    {TK_CONFIG_CUSTOM, "-state", NULL, NULL,
215	NULL, Tk_Offset(Tk_Item, state), TK_CONFIG_NULL_OK, &stateOption},
216    {TK_CONFIG_BITMAP, "-stipple", NULL, NULL,
217	NULL, Tk_Offset(LineItem, outline.stipple), TK_CONFIG_NULL_OK},
218    {TK_CONFIG_CUSTOM, "-tags", NULL, NULL,
219	NULL, 0, TK_CONFIG_NULL_OK, &tagsOption},
220    {TK_CONFIG_CUSTOM, "-width", NULL, NULL,
221	"1.0", Tk_Offset(LineItem, outline.width),
222	TK_CONFIG_DONT_SET_DEFAULT, &pixelOption},
223    {TK_CONFIG_END, NULL, NULL, NULL, NULL, 0, 0}
224};
225
226/*
227 * The structures below defines the line item type by means of functions that
228 * can be invoked by generic item code.
229 */
230
231Tk_ItemType tkLineType = {
232    "line",				/* name */
233    sizeof(LineItem),			/* itemSize */
234    CreateLine,				/* createProc */
235    configSpecs,			/* configSpecs */
236    ConfigureLine,			/* configureProc */
237    LineCoords,				/* coordProc */
238    DeleteLine,				/* deleteProc */
239    DisplayLine,			/* displayProc */
240    TK_CONFIG_OBJS,			/* flags */
241    LineToPoint,			/* pointProc */
242    LineToArea,				/* areaProc */
243    LineToPostscript,			/* postscriptProc */
244    ScaleLine,				/* scaleProc */
245    TranslateLine,			/* translateProc */
246    (Tk_ItemIndexProc *) GetLineIndex,	/* indexProc */
247    NULL,				/* icursorProc */
248    NULL,				/* selectionProc */
249    (Tk_ItemInsertProc *) LineInsert,	/* insertProc */
250    LineDeleteCoords,			/* dTextProc */
251    NULL,				/* nextPtr */
252};
253
254/*
255 * The definition below determines how large are static arrays used to hold
256 * spline points (splines larger than this have to have their arrays
257 * malloc-ed).
258 */
259
260#define MAX_STATIC_POINTS 200
261
262/*
263 *--------------------------------------------------------------
264 *
265 * CreateLine --
266 *
267 *	This function is invoked to create a new line item in a canvas.
268 *
269 * Results:
270 *	A standard Tcl return value. If an error occurred in creating the
271 *	item, then an error message is left in the interp's result; in this
272 *	case itemPtr is left uninitialized, so it can be safely freed by the
273 *	caller.
274 *
275 * Side effects:
276 *	A new line item is created.
277 *
278 *--------------------------------------------------------------
279 */
280
281static int
282CreateLine(
283    Tcl_Interp *interp,		/* Interpreter for error reporting. */
284    Tk_Canvas canvas,		/* Canvas to hold new item. */
285    Tk_Item *itemPtr,		/* Record to hold new item; header has been
286				 * initialized by caller. */
287    int objc,			/* Number of arguments in objv. */
288    Tcl_Obj *CONST objv[])	/* Arguments describing line. */
289{
290    LineItem *linePtr = (LineItem *) itemPtr;
291    int i;
292
293    if (objc == 0) {
294	Tcl_Panic("canvas did not pass any coords\n");
295    }
296
297    /*
298     * Carry out initialization that is needed to set defaults and to allow
299     * proper cleanup after errors during the the remainder of this function.
300     */
301
302    Tk_CreateOutline(&(linePtr->outline));
303    linePtr->canvas = canvas;
304    linePtr->numPoints = 0;
305    linePtr->coordPtr = NULL;
306    linePtr->capStyle = CapButt;
307    linePtr->joinStyle = JoinRound;
308    linePtr->arrowGC = None;
309    linePtr->arrow = ARROWS_NONE;
310    linePtr->arrowShapeA = (float)8.0;
311    linePtr->arrowShapeB = (float)10.0;
312    linePtr->arrowShapeC = (float)3.0;
313    linePtr->firstArrowPtr = NULL;
314    linePtr->lastArrowPtr = NULL;
315    linePtr->smooth = NULL;
316    linePtr->splineSteps = 12;
317
318    /*
319     * Count the number of points and then parse them into a point array.
320     * Leading arguments are assumed to be points if they start with a digit
321     * or a minus sign followed by a digit.
322     */
323
324    for (i = 1; i < objc; i++) {
325	char *arg = Tcl_GetString(objv[i]);
326
327	if ((arg[0] == '-') && (arg[1] >= 'a') && (arg[1] <= 'z')) {
328	    break;
329	}
330    }
331    if (LineCoords(interp, canvas, itemPtr, i, objv) != TCL_OK) {
332	goto error;
333    }
334    if (ConfigureLine(interp, canvas, itemPtr, objc-i, objv+i, 0) == TCL_OK) {
335	return TCL_OK;
336    }
337
338  error:
339    DeleteLine(canvas, itemPtr, Tk_Display(Tk_CanvasTkwin(canvas)));
340    return TCL_ERROR;
341}
342
343/*
344 *--------------------------------------------------------------
345 *
346 * LineCoords --
347 *
348 *	This function is invoked to process the "coords" widget command on
349 *	lines. See the user documentation for details on what it does.
350 *
351 * Results:
352 *	Returns TCL_OK or TCL_ERROR, and sets the interp's result.
353 *
354 * Side effects:
355 *	The coordinates for the given item may be changed.
356 *
357 *--------------------------------------------------------------
358 */
359
360static int
361LineCoords(
362    Tcl_Interp *interp,		/* Used for error reporting. */
363    Tk_Canvas canvas,		/* Canvas containing item. */
364    Tk_Item *itemPtr,		/* Item whose coordinates are to be read or
365				 * modified. */
366    int objc,			/* Number of coordinates supplied in objv. */
367    Tcl_Obj *CONST objv[])	/* Array of coordinates: x1, y1, x2, y2, ... */
368{
369    LineItem *linePtr = (LineItem *) itemPtr;
370    int i, numPoints;
371    double *coordPtr;
372
373    if (objc == 0) {
374	int numCoords;
375	Tcl_Obj *subobj, *obj = Tcl_NewObj();
376
377	numCoords = 2*linePtr->numPoints;
378	if (linePtr->firstArrowPtr != NULL) {
379	    coordPtr = linePtr->firstArrowPtr;
380	} else {
381	    coordPtr = linePtr->coordPtr;
382	}
383	for (i = 0; i < numCoords; i++, coordPtr++) {
384	    if (i == 2) {
385		coordPtr = linePtr->coordPtr+2;
386	    }
387	    if ((linePtr->lastArrowPtr != NULL) && (i == (numCoords-2))) {
388		coordPtr = linePtr->lastArrowPtr;
389	    }
390	    subobj = Tcl_NewDoubleObj(*coordPtr);
391	    Tcl_ListObjAppendElement(interp, obj, subobj);
392	}
393	Tcl_SetObjResult(interp, obj);
394	return TCL_OK;
395    }
396    if (objc == 1) {
397	if (Tcl_ListObjGetElements(interp, objv[0], &objc,
398		(Tcl_Obj ***) &objv) != TCL_OK) {
399	    return TCL_ERROR;
400	}
401    }
402    if (objc & 1) {
403	char buf[64 + TCL_INTEGER_SPACE];
404
405	sprintf(buf, "wrong # coordinates: expected an even number, got %d",
406		objc);
407	Tcl_SetResult(interp, buf, TCL_VOLATILE);
408	return TCL_ERROR;
409    } else if (objc < 4) {
410	char buf[64 + TCL_INTEGER_SPACE];
411
412	sprintf(buf, "wrong # coordinates: expected at least 4, got %d", objc);
413	Tcl_SetResult(interp, buf, TCL_VOLATILE);
414	return TCL_ERROR;
415    } else {
416	numPoints = objc/2;
417	if (linePtr->numPoints != numPoints) {
418	    coordPtr = (double *)
419		    ckalloc((unsigned) (sizeof(double) * objc));
420	    if (linePtr->coordPtr != NULL) {
421		ckfree((char *) linePtr->coordPtr);
422	    }
423	    linePtr->coordPtr = coordPtr;
424	    linePtr->numPoints = numPoints;
425	}
426	coordPtr = linePtr->coordPtr;
427	for (i = 0; i <objc; i++) {
428	    if (Tk_CanvasGetCoordFromObj(interp, canvas, objv[i],
429		    coordPtr++) != TCL_OK) {
430  		return TCL_ERROR;
431  	    }
432  	}
433
434	/*
435	 * Update arrowheads by throwing away any existing arrow-head
436	 * information and calling ConfigureArrows to recompute it.
437	 */
438
439	if (linePtr->firstArrowPtr != NULL) {
440	    ckfree((char *) linePtr->firstArrowPtr);
441	    linePtr->firstArrowPtr = NULL;
442	}
443	if (linePtr->lastArrowPtr != NULL) {
444	    ckfree((char *) linePtr->lastArrowPtr);
445	    linePtr->lastArrowPtr = NULL;
446	}
447	if (linePtr->arrow != ARROWS_NONE) {
448	    ConfigureArrows(canvas, linePtr);
449	}
450	ComputeLineBbox(canvas, linePtr);
451    }
452    return TCL_OK;
453}
454
455/*
456 *--------------------------------------------------------------
457 *
458 * ConfigureLine --
459 *
460 *	This function is invoked to configure various aspects of a line item
461 *	such as its background color.
462 *
463 * Results:
464 *	A standard Tcl result code. If an error occurs, then an error message
465 *	is left in the interp's result.
466 *
467 * Side effects:
468 *	Configuration information, such as colors and stipple patterns, may be
469 *	set for itemPtr.
470 *
471 *--------------------------------------------------------------
472 */
473
474static int
475ConfigureLine(
476    Tcl_Interp *interp,		/* Used for error reporting. */
477    Tk_Canvas canvas,		/* Canvas containing itemPtr. */
478    Tk_Item *itemPtr,		/* Line item to reconfigure. */
479    int objc,			/* Number of elements in objv.  */
480    Tcl_Obj *CONST objv[],	/* Arguments describing things to configure. */
481    int flags)			/* Flags to pass to Tk_ConfigureWidget. */
482{
483    LineItem *linePtr = (LineItem *) itemPtr;
484    XGCValues gcValues;
485    GC newGC, arrowGC;
486    unsigned long mask;
487    Tk_Window tkwin;
488    Tk_State state;
489
490    tkwin = Tk_CanvasTkwin(canvas);
491    if (TCL_OK != Tk_ConfigureWidget(interp, tkwin, configSpecs, objc,
492	    (CONST char **) objv, (char *) linePtr, flags|TK_CONFIG_OBJS)) {
493	return TCL_ERROR;
494    }
495
496    /*
497     * A few of the options require additional processing, such as graphics
498     * contexts.
499     */
500
501    state = itemPtr->state;
502
503    if(state == TK_STATE_NULL) {
504	state = ((TkCanvas *)canvas)->canvas_state;
505    }
506
507    if (linePtr->outline.activeWidth > linePtr->outline.width ||
508	    linePtr->outline.activeDash.number != 0 ||
509	    linePtr->outline.activeColor != NULL ||
510	    linePtr->outline.activeStipple != None) {
511	itemPtr->redraw_flags |= TK_ITEM_STATE_DEPENDANT;
512    } else {
513	itemPtr->redraw_flags &= ~TK_ITEM_STATE_DEPENDANT;
514    }
515    mask = Tk_ConfigOutlineGC(&gcValues, canvas, itemPtr,
516	    &(linePtr->outline));
517    if (mask) {
518	if (linePtr->arrow == ARROWS_NONE) {
519	    gcValues.cap_style = linePtr->capStyle;
520	    mask |= GCCapStyle;
521	}
522	gcValues.join_style = linePtr->joinStyle;
523	mask |= GCJoinStyle;
524	newGC = Tk_GetGC(tkwin, mask, &gcValues);
525#ifdef MAC_OSX_TK
526	/*
527	 * Mac OS X CG drawing needs access to linewidth even for
528	 * arrow fills (as linewidth controls antialiasing).
529	 */
530	mask |= GCLineWidth;
531#else
532	gcValues.line_width = 0;
533#endif
534	arrowGC = Tk_GetGC(tkwin, mask, &gcValues);
535    } else {
536	newGC = arrowGC = None;
537    }
538    if (linePtr->outline.gc != None) {
539	Tk_FreeGC(Tk_Display(tkwin), linePtr->outline.gc);
540    }
541    if (linePtr->arrowGC != None) {
542	Tk_FreeGC(Tk_Display(tkwin), linePtr->arrowGC);
543    }
544    linePtr->outline.gc = newGC;
545    linePtr->arrowGC = arrowGC;
546
547    /*
548     * Keep spline parameters within reasonable limits.
549     */
550
551    if (linePtr->splineSteps < 1) {
552	linePtr->splineSteps = 1;
553    } else if (linePtr->splineSteps > 100) {
554	linePtr->splineSteps = 100;
555    }
556
557    if ((!linePtr->numPoints) || (state==TK_STATE_HIDDEN)) {
558	ComputeLineBbox(canvas, linePtr);
559	return TCL_OK;
560    }
561
562    /*
563     * Setup arrowheads, if needed. If arrowheads are turned off, restore the
564     * line's endpoints (they were shortened when the arrowheads were added).
565     */
566
567    if ((linePtr->firstArrowPtr != NULL) && (linePtr->arrow != ARROWS_FIRST)
568	    && (linePtr->arrow != ARROWS_BOTH)) {
569	linePtr->coordPtr[0] = linePtr->firstArrowPtr[0];
570	linePtr->coordPtr[1] = linePtr->firstArrowPtr[1];
571	ckfree((char *) linePtr->firstArrowPtr);
572	linePtr->firstArrowPtr = NULL;
573    }
574    if ((linePtr->lastArrowPtr != NULL) && (linePtr->arrow != ARROWS_LAST)
575	    && (linePtr->arrow != ARROWS_BOTH)) {
576	int i;
577
578	i = 2*(linePtr->numPoints-1);
579	linePtr->coordPtr[i] = linePtr->lastArrowPtr[0];
580	linePtr->coordPtr[i+1] = linePtr->lastArrowPtr[1];
581	ckfree((char *) linePtr->lastArrowPtr);
582	linePtr->lastArrowPtr = NULL;
583    }
584    if (linePtr->arrow != ARROWS_NONE) {
585	ConfigureArrows(canvas, linePtr);
586    }
587
588    /*
589     * Recompute bounding box for line.
590     */
591
592    ComputeLineBbox(canvas, linePtr);
593
594    return TCL_OK;
595}
596
597/*
598 *--------------------------------------------------------------
599 *
600 * DeleteLine --
601 *
602 *	This function is called to clean up the data structure associated with
603 *	a line item.
604 *
605 * Results:
606 *	None.
607 *
608 * Side effects:
609 *	Resources associated with itemPtr are released.
610 *
611 *--------------------------------------------------------------
612 */
613
614static void
615DeleteLine(
616    Tk_Canvas canvas,		/* Info about overall canvas widget. */
617    Tk_Item *itemPtr,		/* Item that is being deleted. */
618    Display *display)		/* Display containing window for canvas. */
619{
620    LineItem *linePtr = (LineItem *) itemPtr;
621
622    Tk_DeleteOutline(display, &(linePtr->outline));
623    if (linePtr->coordPtr != NULL) {
624	ckfree((char *) linePtr->coordPtr);
625    }
626    if (linePtr->arrowGC != None) {
627	Tk_FreeGC(display, linePtr->arrowGC);
628    }
629    if (linePtr->firstArrowPtr != NULL) {
630	ckfree((char *) linePtr->firstArrowPtr);
631    }
632    if (linePtr->lastArrowPtr != NULL) {
633	ckfree((char *) linePtr->lastArrowPtr);
634    }
635}
636
637/*
638 *--------------------------------------------------------------
639 *
640 * ComputeLineBbox --
641 *
642 *	This function is invoked to compute the bounding box of all the pixels
643 *	that may be drawn as part of a line.
644 *
645 * Results:
646 *	None.
647 *
648 * Side effects:
649 *	The fields x1, y1, x2, and y2 are updated in the header for itemPtr.
650 *
651 *--------------------------------------------------------------
652 */
653
654static void
655ComputeLineBbox(
656    Tk_Canvas canvas,		/* Canvas that contains item. */
657    LineItem *linePtr)		/* Item whose bbos is to be recomputed. */
658{
659    double *coordPtr;
660    int i, intWidth;
661    double width;
662    Tk_State state = linePtr->header.state;
663    Tk_TSOffset *tsoffset;
664
665    if(state == TK_STATE_NULL) {
666	state = ((TkCanvas *)canvas)->canvas_state;
667    }
668
669    if (!(linePtr->numPoints) || (state==TK_STATE_HIDDEN)) {
670	linePtr->header.x1 = -1;
671	linePtr->header.x2 = -1;
672	linePtr->header.y1 = -1;
673	linePtr->header.y2 = -1;
674	return;
675    }
676
677    width = linePtr->outline.width;
678    if (((TkCanvas *)canvas)->currentItemPtr == (Tk_Item *)linePtr) {
679	if (linePtr->outline.activeWidth>width) {
680	    width = linePtr->outline.activeWidth;
681	}
682    } else if (state==TK_STATE_DISABLED) {
683	if (linePtr->outline.disabledWidth>0) {
684	    width = linePtr->outline.disabledWidth;
685	}
686    }
687
688    coordPtr = linePtr->coordPtr;
689    linePtr->header.x1 = linePtr->header.x2 = (int) *coordPtr;
690    linePtr->header.y1 = linePtr->header.y2 = (int) coordPtr[1];
691
692    /*
693     * Compute the bounding box of all the points in the line, then expand in
694     * all directions by the line's width to take care of butting or rounded
695     * corners and projecting or rounded caps. This expansion is an
696     * overestimate (worst-case is square root of two over two) but it's
697     * simple. eDon't do anything special for curves. This causes an
698     * additional overestimate in the bounding box, but is faster.
699     */
700
701    for (i = 1, coordPtr = linePtr->coordPtr+2; i < linePtr->numPoints;
702	    i++, coordPtr += 2) {
703	TkIncludePoint((Tk_Item *) linePtr, coordPtr);
704    }
705    width = linePtr->outline.width;
706    if (width < 1.0) {
707	width = 1.0;
708    }
709    if (linePtr->arrow != ARROWS_NONE) {
710	if (linePtr->arrow != ARROWS_LAST) {
711	    TkIncludePoint((Tk_Item *) linePtr, linePtr->firstArrowPtr);
712	}
713	if (linePtr->arrow != ARROWS_FIRST) {
714	    TkIncludePoint((Tk_Item *) linePtr, linePtr->lastArrowPtr);
715	}
716    }
717
718    tsoffset = &linePtr->outline.tsoffset;
719    if (tsoffset->flags & TK_OFFSET_INDEX) {
720	double *coordPtr = linePtr->coordPtr + (tsoffset->flags & ~TK_OFFSET_INDEX);
721	if (tsoffset->flags <= 0) {
722	    coordPtr = linePtr->coordPtr;
723	    if ((linePtr->arrow == ARROWS_FIRST) || (linePtr->arrow == ARROWS_BOTH)) {
724		coordPtr = linePtr->firstArrowPtr;
725	    }
726	}
727	if (tsoffset->flags > (linePtr->numPoints * 2)) {
728	    coordPtr = linePtr->coordPtr + (linePtr->numPoints * 2);
729	    if ((linePtr->arrow == ARROWS_LAST) || (linePtr->arrow == ARROWS_BOTH)) {
730		coordPtr = linePtr->lastArrowPtr;
731	    }
732	}
733	tsoffset->xoffset = (int) (coordPtr[0] + 0.5);
734	tsoffset->yoffset = (int) (coordPtr[1] + 0.5);
735    } else {
736	if (tsoffset->flags & TK_OFFSET_LEFT) {
737	    tsoffset->xoffset = linePtr->header.x1;
738	} else if (tsoffset->flags & TK_OFFSET_CENTER) {
739	    tsoffset->xoffset = (linePtr->header.x1 + linePtr->header.x2)/2;
740	} else if (tsoffset->flags & TK_OFFSET_RIGHT) {
741	    tsoffset->xoffset = linePtr->header.x2;
742	}
743	if (tsoffset->flags & TK_OFFSET_TOP) {
744	    tsoffset->yoffset = linePtr->header.y1;
745	} else if (tsoffset->flags & TK_OFFSET_MIDDLE) {
746	    tsoffset->yoffset = (linePtr->header.y1 + linePtr->header.y2)/2;
747	} else if (tsoffset->flags & TK_OFFSET_BOTTOM) {
748	    tsoffset->yoffset = linePtr->header.y2;
749	}
750    }
751
752    intWidth = (int) (width + 0.5);
753    linePtr->header.x1 -= intWidth;
754    linePtr->header.x2 += intWidth;
755    linePtr->header.y1 -= intWidth;
756    linePtr->header.y2 += intWidth;
757
758    if (linePtr->numPoints==1) {
759	linePtr->header.x1 -= 1;
760	linePtr->header.x2 += 1;
761	linePtr->header.y1 -= 1;
762	linePtr->header.y2 += 1;
763	return;
764    }
765
766    /*
767     * For mitered lines, make a second pass through all the points. Compute
768     * the locations of the two miter vertex points and add those into the
769     * bounding box.
770     */
771
772    if (linePtr->joinStyle == JoinMiter) {
773	for (i = linePtr->numPoints, coordPtr = linePtr->coordPtr; i >= 3;
774		i--, coordPtr += 2) {
775	    double miter[4];
776	    int j;
777
778	    if (TkGetMiterPoints(coordPtr, coordPtr+2, coordPtr+4,
779		    width, miter, miter+2)) {
780		for (j = 0; j < 4; j += 2) {
781		    TkIncludePoint((Tk_Item *) linePtr, miter+j);
782		}
783	    }
784	}
785    }
786
787    /*
788     * Add in the sizes of arrowheads, if any.
789     */
790
791    if (linePtr->arrow != ARROWS_NONE) {
792	if (linePtr->arrow != ARROWS_LAST) {
793	    for (i = 0, coordPtr = linePtr->firstArrowPtr; i < PTS_IN_ARROW;
794		    i++, coordPtr += 2) {
795		TkIncludePoint((Tk_Item *) linePtr, coordPtr);
796	    }
797	}
798	if (linePtr->arrow != ARROWS_FIRST) {
799	    for (i = 0, coordPtr = linePtr->lastArrowPtr; i < PTS_IN_ARROW;
800		    i++, coordPtr += 2) {
801		TkIncludePoint((Tk_Item *) linePtr, coordPtr);
802	    }
803	}
804    }
805
806    /*
807     * Add one more pixel of fudge factor just to be safe (e.g. X may round
808     * differently than we do).
809     */
810
811    linePtr->header.x1 -= 1;
812    linePtr->header.x2 += 1;
813    linePtr->header.y1 -= 1;
814    linePtr->header.y2 += 1;
815}
816
817/*
818 *--------------------------------------------------------------
819 *
820 * DisplayLine --
821 *
822 *	This function is invoked to draw a line item in a given drawable.
823 *
824 * Results:
825 *	None.
826 *
827 * Side effects:
828 *	ItemPtr is drawn in drawable using the transformation information in
829 *	canvas.
830 *
831 *--------------------------------------------------------------
832 */
833
834static void
835DisplayLine(
836    Tk_Canvas canvas,		/* Canvas that contains item. */
837    Tk_Item *itemPtr,		/* Item to be displayed. */
838    Display *display,		/* Display on which to draw item. */
839    Drawable drawable,		/* Pixmap or window in which to draw item. */
840    int x, int y, int width, int height)
841				/* Describes region of canvas that must be
842				 * redisplayed (not used). */
843{
844    LineItem *linePtr = (LineItem *) itemPtr;
845    XPoint staticPoints[MAX_STATIC_POINTS*3];
846    XPoint *pointPtr;
847    double linewidth;
848    int numPoints;
849    Tk_State state = itemPtr->state;
850
851    if ((!linePtr->numPoints)||(linePtr->outline.gc==None)) {
852	return;
853    }
854
855    if (state == TK_STATE_NULL) {
856	    state = ((TkCanvas *)canvas)->canvas_state;
857    }
858    linewidth = linePtr->outline.width;
859    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
860	if (linePtr->outline.activeWidth != linewidth) {
861	    linewidth = linePtr->outline.activeWidth;
862	}
863    } else if (state==TK_STATE_DISABLED) {
864	if (linePtr->outline.disabledWidth != linewidth) {
865	    linewidth = linePtr->outline.disabledWidth;
866	}
867    }
868    /*
869     * Build up an array of points in screen coordinates. Use a static array
870     * unless the line has an enormous number of points; in this case,
871     * dynamically allocate an array. For smoothed lines, generate the curve
872     * points on each redisplay.
873     */
874
875    if ((linePtr->smooth) && (linePtr->numPoints > 2)) {
876	numPoints = linePtr->smooth->coordProc(canvas, NULL,
877		linePtr->numPoints, linePtr->splineSteps, NULL, NULL);
878    } else {
879	numPoints = linePtr->numPoints;
880    }
881
882    if (numPoints <= MAX_STATIC_POINTS) {
883	pointPtr = staticPoints;
884    } else {
885	pointPtr = (XPoint *)ckalloc((unsigned)(numPoints * 3*sizeof(XPoint)));
886    }
887
888    if ((linePtr->smooth) && (linePtr->numPoints > 2)) {
889	numPoints = linePtr->smooth->coordProc(canvas, linePtr->coordPtr,
890		linePtr->numPoints, linePtr->splineSteps, pointPtr, NULL);
891    } else {
892	numPoints = TkCanvTranslatePath((TkCanvas*)canvas, numPoints,
893		linePtr->coordPtr, 0, pointPtr);
894    }
895
896    /*
897     * Display line, the free up line storage if it was dynamically allocated.
898     * If we're stippling, then modify the stipple offset in the GC. Be sure
899     * to reset the offset when done, since the GC is supposed to be
900     * read-only.
901     */
902
903    if (Tk_ChangeOutlineGC(canvas, itemPtr, &(linePtr->outline))) {
904	Tk_CanvasSetOffset(canvas, linePtr->arrowGC, &linePtr->outline.tsoffset);
905    }
906    if (numPoints>1) {
907	XDrawLines(display, drawable, linePtr->outline.gc, pointPtr, numPoints,
908	    CoordModeOrigin);
909    } else {
910	int intwidth = (int) (linewidth + 0.5);
911        if (intwidth<1) {
912	    intwidth=1;
913	}
914	XFillArc(display, drawable, linePtr->outline.gc,
915		pointPtr->x - intwidth/2, pointPtr->y - intwidth/2,
916		(unsigned int)intwidth+1, (unsigned int)intwidth+1, 0, 64*360);
917    }
918    if (pointPtr != staticPoints) {
919	ckfree((char *) pointPtr);
920    }
921
922    /*
923     * Display arrowheads, if they are wanted.
924     */
925
926    if (linePtr->firstArrowPtr != NULL) {
927	TkFillPolygon(canvas, linePtr->firstArrowPtr, PTS_IN_ARROW,
928		display, drawable, linePtr->arrowGC, NULL);
929    }
930    if (linePtr->lastArrowPtr != NULL) {
931	TkFillPolygon(canvas, linePtr->lastArrowPtr, PTS_IN_ARROW,
932		display, drawable, linePtr->arrowGC, NULL);
933    }
934    if (Tk_ResetOutlineGC(canvas, itemPtr, &(linePtr->outline))) {
935	XSetTSOrigin(display, linePtr->arrowGC, 0, 0);
936    }
937}
938
939/*
940 *--------------------------------------------------------------
941 *
942 * LineInsert --
943 *
944 *	Insert coords into a line item at a given index.
945 *
946 * Results:
947 *	None.
948 *
949 * Side effects:
950 *	The coords in the given item is modified.
951 *
952 *--------------------------------------------------------------
953 */
954
955static void
956LineInsert(
957    Tk_Canvas canvas,		/* Canvas containing text item. */
958    Tk_Item *itemPtr,		/* Line item to be modified. */
959    int beforeThis,		/* Index before which new coordinates are to
960				 * be inserted. */
961    Tcl_Obj *obj)		/* New coordinates to be inserted. */
962{
963    LineItem *linePtr = (LineItem *) itemPtr;
964    int length, objc, i;
965    double *newCoordPtr, *coordPtr;
966    Tk_State state = itemPtr->state;
967    Tcl_Obj **objv;
968
969    if (state == TK_STATE_NULL) {
970	state = ((TkCanvas *)canvas)->canvas_state;
971    }
972
973    if (!obj || (Tcl_ListObjGetElements(NULL, obj, &objc, &objv) != TCL_OK)
974	    || !objc || objc&1) {
975	return;
976    }
977    length = 2*linePtr->numPoints;
978    if (beforeThis < 0) {
979	beforeThis = 0;
980    }
981    if (beforeThis > length) {
982	beforeThis = length;
983    }
984    if (linePtr->firstArrowPtr != NULL) {
985	linePtr->coordPtr[0] = linePtr->firstArrowPtr[0];
986	linePtr->coordPtr[1] = linePtr->firstArrowPtr[1];
987    }
988    if (linePtr->lastArrowPtr != NULL) {
989	linePtr->coordPtr[length-2] = linePtr->lastArrowPtr[0];
990	linePtr->coordPtr[length-1] = linePtr->lastArrowPtr[1];
991    }
992    newCoordPtr = (double *)
993	    ckalloc(sizeof(double) * (unsigned)(length + objc));
994    for (i=0; i<beforeThis; i++) {
995	newCoordPtr[i] = linePtr->coordPtr[i];
996    }
997    for (i=0; i<objc; i++) {
998	if (Tcl_GetDoubleFromObj(NULL, objv[i],
999		&newCoordPtr[i + beforeThis]) != TCL_OK) {
1000	    Tcl_ResetResult(((TkCanvas *)canvas)->interp);
1001	    ckfree((char *) newCoordPtr);
1002	    return;
1003	}
1004    }
1005
1006    for (i=beforeThis; i<length; i++) {
1007	newCoordPtr[i+objc] = linePtr->coordPtr[i];
1008    }
1009    if (linePtr->coordPtr) {
1010	ckfree((char *)linePtr->coordPtr);
1011    }
1012    linePtr->coordPtr = newCoordPtr;
1013    linePtr->numPoints = (length + objc)/2;
1014
1015    if ((length>3) && (state != TK_STATE_HIDDEN)) {
1016	/*
1017	 * This is some optimizing code that will result that only the part of
1018	 * the polygon that changed (and the objects that are overlapping with
1019	 * that part) need to be redrawn. A special flag is set that instructs
1020	 * the general canvas code not to redraw the whole object. If this
1021	 * flag is not set, the canvas will do the redrawing, otherwise I have
1022	 * to do it here.
1023	 */
1024
1025	itemPtr->redraw_flags |= TK_ITEM_DONT_REDRAW;
1026
1027	if (beforeThis>0) {beforeThis -= 2; objc+=2; }
1028	if ((beforeThis+objc)<length) objc+=2;
1029	if (linePtr->smooth) {
1030	    if(beforeThis>0) {
1031		beforeThis-=2; objc+=2;
1032	    }
1033	    if((beforeThis+objc+2)<length) {
1034		objc+=2;
1035	    }
1036	}
1037	itemPtr->x1 = itemPtr->x2 = (int) linePtr->coordPtr[beforeThis];
1038	itemPtr->y1 = itemPtr->y2 = (int) linePtr->coordPtr[beforeThis+1];
1039	if ((linePtr->firstArrowPtr != NULL) && (beforeThis<1)) {
1040	    /*
1041	     * Include old first arrow.
1042	     */
1043
1044	    for (i = 0, coordPtr = linePtr->firstArrowPtr; i < PTS_IN_ARROW;
1045		    i++, coordPtr += 2) {
1046		TkIncludePoint(itemPtr, coordPtr);
1047	    }
1048	}
1049	if ((linePtr->lastArrowPtr != NULL) && ((beforeThis+objc)>=length)) {
1050	    /*
1051	     * Include old last arrow.
1052	     */
1053
1054	    for (i = 0, coordPtr = linePtr->lastArrowPtr; i < PTS_IN_ARROW;
1055		    i++, coordPtr += 2) {
1056		TkIncludePoint(itemPtr, coordPtr);
1057	    }
1058	}
1059	coordPtr = linePtr->coordPtr+beforeThis+2;
1060	for (i=2; i<objc; i+=2) {
1061	    TkIncludePoint(itemPtr, coordPtr);
1062	    coordPtr+=2;
1063	}
1064    }
1065    if (linePtr->firstArrowPtr != NULL) {
1066	ckfree((char *) linePtr->firstArrowPtr);
1067	linePtr->firstArrowPtr = NULL;
1068    }
1069    if (linePtr->lastArrowPtr != NULL) {
1070	ckfree((char *) linePtr->lastArrowPtr);
1071	linePtr->lastArrowPtr = NULL;
1072    }
1073    if (linePtr->arrow != ARROWS_NONE) {
1074	ConfigureArrows(canvas, linePtr);
1075    }
1076
1077    if (itemPtr->redraw_flags & TK_ITEM_DONT_REDRAW) {
1078	double width;
1079	int intWidth;
1080
1081	if ((linePtr->firstArrowPtr != NULL) && (beforeThis>2)) {
1082	    /*
1083	     * Include new first arrow.
1084	     */
1085
1086	    for (i = 0, coordPtr = linePtr->firstArrowPtr; i < PTS_IN_ARROW;
1087		    i++, coordPtr += 2) {
1088		TkIncludePoint(itemPtr, coordPtr);
1089	    }
1090	}
1091	if ((linePtr->lastArrowPtr != NULL) && (beforeThis+objc < length-2)) {
1092	    /*
1093	     * Include new right arrow.
1094	     */
1095
1096	    for (i = 0, coordPtr = linePtr->lastArrowPtr; i < PTS_IN_ARROW;
1097		    i++, coordPtr += 2) {
1098		TkIncludePoint(itemPtr, coordPtr);
1099	    }
1100	}
1101	width = linePtr->outline.width;
1102	if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
1103	    if (linePtr->outline.activeWidth>width) {
1104		width = linePtr->outline.activeWidth;
1105	    }
1106	} else if (state==TK_STATE_DISABLED) {
1107	    if (linePtr->outline.disabledWidth>0) {
1108		width = linePtr->outline.disabledWidth;
1109	    }
1110	}
1111	intWidth = (int) (width + 0.5);
1112	if (intWidth < 1) {
1113	    intWidth = 1;
1114	}
1115	itemPtr->x1 -= intWidth; itemPtr->y1 -= intWidth;
1116	itemPtr->x2 += intWidth; itemPtr->y2 += intWidth;
1117	Tk_CanvasEventuallyRedraw(canvas, itemPtr->x1, itemPtr->y1,
1118		itemPtr->x2, itemPtr->y2);
1119    }
1120
1121    ComputeLineBbox(canvas, linePtr);
1122}
1123
1124/*
1125 *--------------------------------------------------------------
1126 *
1127 * LineDeleteCoords --
1128 *
1129 *	Delete one or more coordinates from a line item.
1130 *
1131 * Results:
1132 *	None.
1133 *
1134 * Side effects:
1135 *	Characters between "first" and "last", inclusive, get deleted from
1136 *	itemPtr.
1137 *
1138 *--------------------------------------------------------------
1139 */
1140
1141static void
1142LineDeleteCoords(
1143    Tk_Canvas canvas,		/* Canvas containing itemPtr. */
1144    Tk_Item *itemPtr,		/* Item in which to delete characters. */
1145    int first,			/* Index of first character to delete. */
1146    int last)			/* Index of last character to delete. */
1147{
1148    LineItem *linePtr = (LineItem *) itemPtr;
1149    int count, i, first1, last1;
1150    int length = 2*linePtr->numPoints;
1151    double *coordPtr;
1152    Tk_State state = itemPtr->state;
1153
1154    if (state == TK_STATE_NULL) {
1155	state = ((TkCanvas *)canvas)->canvas_state;
1156    }
1157
1158    first &= -2;
1159    last &= -2;
1160
1161    if (first < 0) {
1162	first = 0;
1163    }
1164    if (last >= length) {
1165	last = length-2;
1166    }
1167    if (first > last) {
1168	return;
1169    }
1170    if (linePtr->firstArrowPtr != NULL) {
1171	linePtr->coordPtr[0] = linePtr->firstArrowPtr[0];
1172	linePtr->coordPtr[1] = linePtr->firstArrowPtr[1];
1173    }
1174    if (linePtr->lastArrowPtr != NULL) {
1175	linePtr->coordPtr[length-2] = linePtr->lastArrowPtr[0];
1176	linePtr->coordPtr[length-1] = linePtr->lastArrowPtr[1];
1177    }
1178    first1 = first;
1179    last1 = last;
1180    if (first1 > 0) {
1181	first1 -= 2;
1182    }
1183    if (last1 < length-2) {
1184	last1 += 2;
1185    }
1186    if (linePtr->smooth) {
1187	if (first1 > 0) {
1188	    first1 -= 2;
1189	}
1190	if (last1 < length-2) {
1191	    last1 += 2;
1192	}
1193    }
1194
1195    if (!(first1 < 2) && (last1 >= length-2)) {
1196	/*
1197	 * This is some optimizing code that will result that only the part of
1198	 * the line that changed (and the objects that are overlapping with
1199	 * that part) need to be redrawn. A special flag is set that instructs
1200	 * the general canvas code not to redraw the whole object. If this
1201	 * flag is set, the redrawing has to be done here, otherwise the
1202	 * general Canvas code will take care of it.
1203	 */
1204
1205	itemPtr->redraw_flags |= TK_ITEM_DONT_REDRAW;
1206	itemPtr->x1 = itemPtr->x2 = (int) linePtr->coordPtr[first1];
1207	itemPtr->y1 = itemPtr->y2 = (int) linePtr->coordPtr[first1+1];
1208	if ((linePtr->firstArrowPtr != NULL) && (first1 < 2)) {
1209	    /*
1210	     * Include old first arrow.
1211	     */
1212
1213	    for (i = 0, coordPtr = linePtr->firstArrowPtr; i < PTS_IN_ARROW;
1214		    i++, coordPtr += 2) {
1215		TkIncludePoint(itemPtr, coordPtr);
1216	    }
1217	}
1218	if ((linePtr->lastArrowPtr != NULL) && (last1 >= length-2)) {
1219	    /*
1220	     * Include old last arrow.
1221	     */
1222
1223	    for (i = 0, coordPtr = linePtr->lastArrowPtr; i < PTS_IN_ARROW;
1224		    i++, coordPtr += 2) {
1225		TkIncludePoint(itemPtr, coordPtr);
1226	    }
1227	}
1228	coordPtr = linePtr->coordPtr+first1+2;
1229	for (i=first1+2; i<=last1; i+=2) {
1230	    TkIncludePoint(itemPtr, coordPtr);
1231	    coordPtr += 2;
1232	}
1233    }
1234
1235    count = last + 2 - first;
1236    for (i=last+2; i<length; i++) {
1237	linePtr->coordPtr[i-count] = linePtr->coordPtr[i];
1238    }
1239    linePtr->numPoints -= count/2;
1240    if (linePtr->firstArrowPtr != NULL) {
1241	ckfree((char *) linePtr->firstArrowPtr);
1242	linePtr->firstArrowPtr = NULL;
1243    }
1244    if (linePtr->lastArrowPtr != NULL) {
1245	ckfree((char *) linePtr->lastArrowPtr);
1246	linePtr->lastArrowPtr = NULL;
1247    }
1248    if (linePtr->arrow != ARROWS_NONE) {
1249	ConfigureArrows(canvas, linePtr);
1250    }
1251    if (itemPtr->redraw_flags & TK_ITEM_DONT_REDRAW) {
1252	double width;
1253	int intWidth;
1254
1255	if ((linePtr->firstArrowPtr != NULL) && (first1 < 4)) {
1256	    /*
1257	     * Include new first arrow.
1258	     */
1259
1260	    for (i = 0, coordPtr = linePtr->firstArrowPtr; i < PTS_IN_ARROW;
1261		    i++, coordPtr += 2) {
1262		TkIncludePoint(itemPtr, coordPtr);
1263	    }
1264	}
1265	if ((linePtr->lastArrowPtr != NULL) && (last1 > length-4)) {
1266	    /*
1267	     * Include new right arrow.
1268	     */
1269
1270	    for (i = 0, coordPtr = linePtr->lastArrowPtr; i < PTS_IN_ARROW;
1271		    i++, coordPtr += 2) {
1272		TkIncludePoint(itemPtr, coordPtr);
1273	    }
1274	}
1275	width = linePtr->outline.width;
1276	if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
1277	    if (linePtr->outline.activeWidth > width) {
1278		width = linePtr->outline.activeWidth;
1279	    }
1280	} else if (state==TK_STATE_DISABLED) {
1281	    if (linePtr->outline.disabledWidth > 0) {
1282		width = linePtr->outline.disabledWidth;
1283	    }
1284	}
1285	intWidth = (int) (width + 0.5);
1286	if (intWidth < 1) {
1287	    intWidth = 1;
1288	}
1289	itemPtr->x1 -= intWidth;
1290	itemPtr->y1 -= intWidth;
1291	itemPtr->x2 += intWidth;
1292	itemPtr->y2 += intWidth;
1293	Tk_CanvasEventuallyRedraw(canvas, itemPtr->x1, itemPtr->y1,
1294		itemPtr->x2, itemPtr->y2);
1295    }
1296    ComputeLineBbox(canvas, linePtr);
1297}
1298
1299/*
1300 *--------------------------------------------------------------
1301 *
1302 * LineToPoint --
1303 *
1304 *	Computes the distance from a given point to a given line, in canvas
1305 *	units.
1306 *
1307 * Results:
1308 *	The return value is 0 if the point whose x and y coordinates are
1309 *	pointPtr[0] and pointPtr[1] is inside the line. If the point isn't
1310 *	inside the line then the return value is the distance from the point
1311 *	to the line.
1312 *
1313 * Side effects:
1314 *	None.
1315 *
1316 *--------------------------------------------------------------
1317 */
1318
1319	/* ARGSUSED */
1320static double
1321LineToPoint(
1322    Tk_Canvas canvas,		/* Canvas containing item. */
1323    Tk_Item *itemPtr,		/* Item to check against point. */
1324    double *pointPtr)		/* Pointer to x and y coordinates. */
1325{
1326    Tk_State state = itemPtr->state;
1327    LineItem *linePtr = (LineItem *) itemPtr;
1328    double *coordPtr, *linePoints;
1329    double staticSpace[2*MAX_STATIC_POINTS];
1330    double poly[10];
1331    double bestDist, dist, width;
1332    int numPoints, count;
1333    int changedMiterToBevel;	/* Non-zero means that a mitered corner had to
1334				 * be treated as beveled after all because the
1335				 * angle was < 11 degrees. */
1336
1337    bestDist = 1.0e36;
1338
1339    /*
1340     * Handle smoothed lines by generating an expanded set of points against
1341     * which to do the check.
1342     */
1343
1344    if(state == TK_STATE_NULL) {
1345	state = ((TkCanvas *)canvas)->canvas_state;
1346    }
1347
1348    width = linePtr->outline.width;
1349    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
1350	if (linePtr->outline.activeWidth>width) {
1351	    width = linePtr->outline.activeWidth;
1352	}
1353    } else if (state==TK_STATE_DISABLED) {
1354	if (linePtr->outline.disabledWidth>0) {
1355	    width = linePtr->outline.disabledWidth;
1356	}
1357    }
1358
1359    if ((linePtr->smooth) && (linePtr->numPoints > 2)) {
1360	numPoints = linePtr->smooth->coordProc(canvas, NULL,
1361		linePtr->numPoints, linePtr->splineSteps, NULL, NULL);
1362	if (numPoints <= MAX_STATIC_POINTS) {
1363	    linePoints = staticSpace;
1364	} else {
1365	    linePoints = (double *) ckalloc((unsigned)
1366		    (2*numPoints*sizeof(double)));
1367	}
1368	numPoints = linePtr->smooth->coordProc(canvas, linePtr->coordPtr,
1369		linePtr->numPoints, linePtr->splineSteps, NULL, linePoints);
1370    } else {
1371	numPoints = linePtr->numPoints;
1372	linePoints = linePtr->coordPtr;
1373    }
1374
1375    if (width < 1.0) {
1376	width = 1.0;
1377    }
1378
1379    if (!numPoints || itemPtr->state==TK_STATE_HIDDEN) {
1380	return bestDist;
1381    } else if (numPoints == 1) {
1382	bestDist = hypot(linePoints[0]-pointPtr[0], linePoints[1]-pointPtr[1])
1383		- width/2.0;
1384	if (bestDist < 0) bestDist = 0;
1385	return bestDist;
1386    }
1387
1388    /*
1389     * The overall idea is to iterate through all of the edges of the line,
1390     * computing a polygon for each edge and testing the point against that
1391     * polygon. In addition, there are additional tests to deal with rounded
1392     * joints and caps.
1393     */
1394
1395    changedMiterToBevel = 0;
1396    for (count = numPoints, coordPtr = linePoints; count >= 2;
1397	    count--, coordPtr += 2) {
1398	/*
1399	 * If rounding is done around the first point then compute the
1400	 * distance between the point and the point.
1401	 */
1402
1403	if (((linePtr->capStyle == CapRound) && (count == numPoints))
1404		|| ((linePtr->joinStyle == JoinRound)
1405			&& (count != numPoints))) {
1406	    dist = hypot(coordPtr[0] - pointPtr[0], coordPtr[1] - pointPtr[1])
1407		    - width/2.0;
1408	    if (dist <= 0.0) {
1409		bestDist = 0.0;
1410		goto done;
1411	    } else if (dist < bestDist) {
1412		bestDist = dist;
1413	    }
1414	}
1415
1416	/*
1417	 * Compute the polygonal shape corresponding to this edge, consisting
1418	 * of two points for the first point of the edge and two points for
1419	 * the last point of the edge.
1420	 */
1421
1422	if (count == numPoints) {
1423	    TkGetButtPoints(coordPtr+2, coordPtr, width,
1424		    linePtr->capStyle == CapProjecting, poly, poly+2);
1425	} else if ((linePtr->joinStyle == JoinMiter) && !changedMiterToBevel) {
1426	    poly[0] = poly[6];
1427	    poly[1] = poly[7];
1428	    poly[2] = poly[4];
1429	    poly[3] = poly[5];
1430	} else {
1431	    TkGetButtPoints(coordPtr+2, coordPtr, width, 0, poly, poly+2);
1432
1433	    /*
1434	     * If this line uses beveled joints, then check the distance to a
1435	     * polygon comprising the last two points of the previous polygon
1436	     * and the first two from this polygon; this checks the wedges
1437	     * that fill the mitered joint.
1438	     */
1439
1440	    if ((linePtr->joinStyle == JoinBevel) || changedMiterToBevel) {
1441		poly[8] = poly[0];
1442		poly[9] = poly[1];
1443		dist = TkPolygonToPoint(poly, 5, pointPtr);
1444		if (dist <= 0.0) {
1445		    bestDist = 0.0;
1446		    goto done;
1447		} else if (dist < bestDist) {
1448		    bestDist = dist;
1449		}
1450		changedMiterToBevel = 0;
1451	    }
1452	}
1453	if (count == 2) {
1454	    TkGetButtPoints(coordPtr, coordPtr+2, width,
1455		    linePtr->capStyle == CapProjecting, poly+4, poly+6);
1456	} else if (linePtr->joinStyle == JoinMiter) {
1457	    if (TkGetMiterPoints(coordPtr, coordPtr+2, coordPtr+4,
1458		    width, poly+4, poly+6) == 0) {
1459		changedMiterToBevel = 1;
1460		TkGetButtPoints(coordPtr, coordPtr+2, width, 0,
1461			poly+4, poly+6);
1462	    }
1463	} else {
1464	    TkGetButtPoints(coordPtr, coordPtr+2, width, 0,
1465		    poly+4, poly+6);
1466	}
1467	poly[8] = poly[0];
1468	poly[9] = poly[1];
1469	dist = TkPolygonToPoint(poly, 5, pointPtr);
1470	if (dist <= 0.0) {
1471	    bestDist = 0.0;
1472	    goto done;
1473	} else if (dist < bestDist) {
1474	    bestDist = dist;
1475	}
1476    }
1477
1478    /*
1479     * If caps are rounded, check the distance to the cap around the final end
1480     * point of the line.
1481     */
1482
1483    if (linePtr->capStyle == CapRound) {
1484	dist = hypot(coordPtr[0] - pointPtr[0], coordPtr[1] - pointPtr[1])
1485		- width/2.0;
1486	if (dist <= 0.0) {
1487	    bestDist = 0.0;
1488	    goto done;
1489	} else if (dist < bestDist) {
1490	    bestDist = dist;
1491	}
1492    }
1493
1494    /*
1495     * If there are arrowheads, check the distance to the arrowheads.
1496     */
1497
1498    if (linePtr->arrow != ARROWS_NONE) {
1499	if (linePtr->arrow != ARROWS_LAST) {
1500	    dist = TkPolygonToPoint(linePtr->firstArrowPtr, PTS_IN_ARROW,
1501		    pointPtr);
1502	    if (dist <= 0.0) {
1503		bestDist = 0.0;
1504		goto done;
1505	    } else if (dist < bestDist) {
1506		bestDist = dist;
1507	    }
1508	}
1509	if (linePtr->arrow != ARROWS_FIRST) {
1510	    dist = TkPolygonToPoint(linePtr->lastArrowPtr, PTS_IN_ARROW,
1511		    pointPtr);
1512	    if (dist <= 0.0) {
1513		bestDist = 0.0;
1514		goto done;
1515	    } else if (dist < bestDist) {
1516		bestDist = dist;
1517	    }
1518	}
1519    }
1520
1521  done:
1522    if ((linePoints != staticSpace) && (linePoints != linePtr->coordPtr)) {
1523	ckfree((char *) linePoints);
1524    }
1525    return bestDist;
1526}
1527
1528/*
1529 *--------------------------------------------------------------
1530 *
1531 * LineToArea --
1532 *
1533 *	This function is called to determine whether an item lies entirely
1534 *	inside, entirely outside, or overlapping a given rectangular area.
1535 *
1536 * Results:
1537 *	-1 is returned if the item is entirely outside the area, 0 if it
1538 *	overlaps, and 1 if it is entirely inside the given area.
1539 *
1540 * Side effects:
1541 *	None.
1542 *
1543 *--------------------------------------------------------------
1544 */
1545
1546	/* ARGSUSED */
1547static int
1548LineToArea(
1549    Tk_Canvas canvas,		/* Canvas containing item. */
1550    Tk_Item *itemPtr,		/* Item to check against line. */
1551    double *rectPtr)
1552{
1553    LineItem *linePtr = (LineItem *) itemPtr;
1554    double staticSpace[2*MAX_STATIC_POINTS];
1555    double *linePoints;
1556    int numPoints, result;
1557    double radius, width;
1558    Tk_State state = itemPtr->state;
1559
1560    if(state == TK_STATE_NULL) {
1561	state = ((TkCanvas *)canvas)->canvas_state;
1562    }
1563    width = linePtr->outline.width;
1564    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
1565	if (linePtr->outline.activeWidth>width) {
1566	    width = linePtr->outline.activeWidth;
1567	}
1568    } else if (state==TK_STATE_DISABLED) {
1569	if (linePtr->outline.disabledWidth>0) {
1570	    width = linePtr->outline.disabledWidth;
1571	}
1572    }
1573
1574    radius = (width+1.0)/2.0;
1575
1576    if ((state==TK_STATE_HIDDEN) || !linePtr->numPoints) {
1577	return -1;
1578    } else if (linePtr->numPoints == 1) {
1579	double oval[4];
1580
1581	oval[0] = linePtr->coordPtr[0]-radius;
1582	oval[1] = linePtr->coordPtr[1]-radius;
1583	oval[2] = linePtr->coordPtr[0]+radius;
1584	oval[3] = linePtr->coordPtr[1]+radius;
1585	return TkOvalToArea(oval, rectPtr);
1586    }
1587
1588    /*
1589     * Handle smoothed lines by generating an expanded set of points against
1590     * which to do the check.
1591     */
1592
1593    if ((linePtr->smooth) && (linePtr->numPoints > 2)) {
1594	numPoints = linePtr->smooth->coordProc(canvas, NULL,
1595		linePtr->numPoints, linePtr->splineSteps, NULL, NULL);
1596	if (numPoints <= MAX_STATIC_POINTS) {
1597	    linePoints = staticSpace;
1598	} else {
1599	    linePoints = (double *) ckalloc((unsigned)
1600		    (2*numPoints*sizeof(double)));
1601	}
1602	numPoints = linePtr->smooth->coordProc(canvas, linePtr->coordPtr,
1603		linePtr->numPoints, linePtr->splineSteps, NULL, linePoints);
1604    } else {
1605	numPoints = linePtr->numPoints;
1606	linePoints = linePtr->coordPtr;
1607    }
1608
1609    /*
1610     * Check the segments of the line.
1611     */
1612
1613     if (width < 1.0) {
1614	width = 1.0;
1615    }
1616
1617    result = TkThickPolyLineToArea(linePoints, numPoints,
1618	    width, linePtr->capStyle, linePtr->joinStyle,
1619	    rectPtr);
1620    if (result == 0) {
1621	goto done;
1622    }
1623
1624    /*
1625     * Check arrowheads, if any.
1626     */
1627
1628    if (linePtr->arrow != ARROWS_NONE) {
1629	if (linePtr->arrow != ARROWS_LAST) {
1630	    if (TkPolygonToArea(linePtr->firstArrowPtr, PTS_IN_ARROW,
1631		    rectPtr) != result) {
1632		result = 0;
1633		goto done;
1634	    }
1635	}
1636	if (linePtr->arrow != ARROWS_FIRST) {
1637	    if (TkPolygonToArea(linePtr->lastArrowPtr, PTS_IN_ARROW,
1638		    rectPtr) != result) {
1639		result = 0;
1640		goto done;
1641	    }
1642	}
1643    }
1644
1645  done:
1646    if ((linePoints != staticSpace) && (linePoints != linePtr->coordPtr)) {
1647	ckfree((char *) linePoints);
1648    }
1649    return result;
1650}
1651
1652/*
1653 *--------------------------------------------------------------
1654 *
1655 * ScaleLine --
1656 *
1657 *	This function is invoked to rescale a line item.
1658 *
1659 * Results:
1660 *	None.
1661 *
1662 * Side effects:
1663 *	The line referred to by itemPtr is rescaled so that the following
1664 *	transformation is applied to all point coordinates:
1665 *		x' = originX + scaleX*(x-originX)
1666 *		y' = originY + scaleY*(y-originY)
1667 *
1668 *--------------------------------------------------------------
1669 */
1670
1671static void
1672ScaleLine(
1673    Tk_Canvas canvas,		/* Canvas containing line. */
1674    Tk_Item *itemPtr,		/* Line to be scaled. */
1675    double originX, double originY,
1676				/* Origin about which to scale rect. */
1677    double scaleX,		/* Amount to scale in X direction. */
1678    double scaleY)		/* Amount to scale in Y direction. */
1679{
1680    LineItem *linePtr = (LineItem *) itemPtr;
1681    double *coordPtr;
1682    int i;
1683
1684    /*
1685     * Delete any arrowheads before scaling all the points (so that the
1686     * end-points of the line get restored).
1687     */
1688
1689    if (linePtr->firstArrowPtr != NULL) {
1690	linePtr->coordPtr[0] = linePtr->firstArrowPtr[0];
1691	linePtr->coordPtr[1] = linePtr->firstArrowPtr[1];
1692	ckfree((char *) linePtr->firstArrowPtr);
1693	linePtr->firstArrowPtr = NULL;
1694    }
1695    if (linePtr->lastArrowPtr != NULL) {
1696	int i;
1697
1698	i = 2*(linePtr->numPoints-1);
1699	linePtr->coordPtr[i] = linePtr->lastArrowPtr[0];
1700	linePtr->coordPtr[i+1] = linePtr->lastArrowPtr[1];
1701	ckfree((char *) linePtr->lastArrowPtr);
1702	linePtr->lastArrowPtr = NULL;
1703    }
1704    for (i = 0, coordPtr = linePtr->coordPtr; i < linePtr->numPoints;
1705	    i++, coordPtr += 2) {
1706	coordPtr[0] = originX + scaleX*(*coordPtr - originX);
1707	coordPtr[1] = originY + scaleY*(coordPtr[1] - originY);
1708    }
1709    if (linePtr->arrow != ARROWS_NONE) {
1710	ConfigureArrows(canvas, linePtr);
1711    }
1712    ComputeLineBbox(canvas, linePtr);
1713}
1714
1715/*
1716 *--------------------------------------------------------------
1717 *
1718 * GetLineIndex --
1719 *
1720 *	Parse an index into a line item and return either its value or an
1721 *	error.
1722 *
1723 * Results:
1724 *	A standard Tcl result. If all went well, then *indexPtr is filled in
1725 *	with the index (into itemPtr) corresponding to string. Otherwise an
1726 *	error message is left in interp->result.
1727 *
1728 * Side effects:
1729 *	None.
1730 *
1731 *--------------------------------------------------------------
1732 */
1733
1734static int
1735GetLineIndex(
1736    Tcl_Interp *interp,		/* Used for error reporting. */
1737    Tk_Canvas canvas,		/* Canvas containing item. */
1738    Tk_Item *itemPtr,		/* Item for which the index is being
1739				 * specified. */
1740    Tcl_Obj *obj,		/* Specification of a particular coord in
1741				 * itemPtr's line. */
1742    int *indexPtr)		/* Where to store converted index. */
1743{
1744    LineItem *linePtr = (LineItem *) itemPtr;
1745    int length;
1746    char *string = Tcl_GetStringFromObj(obj, &length);
1747
1748    if (string[0] == 'e') {
1749	if (strncmp(string, "end", (unsigned) length) == 0) {
1750	    *indexPtr = 2*linePtr->numPoints;
1751	} else {
1752	    /*
1753	     * Some of the paths here leave messages in interp->result, so we
1754	     * have to clear it out before storing our own message.
1755	     */
1756
1757	badIndex:
1758	    Tcl_SetResult(interp, NULL, TCL_STATIC);
1759	    Tcl_AppendResult(interp, "bad index \"", string, "\"", NULL);
1760	    return TCL_ERROR;
1761	}
1762    } else if (string[0] == '@') {
1763	int i;
1764	double x ,y, bestDist, dist, *coordPtr;
1765	char *end, *p;
1766
1767	p = string+1;
1768	x = strtod(p, &end);
1769	if ((end == p) || (*end != ',')) {
1770	    goto badIndex;
1771	}
1772	p = end+1;
1773	y = strtod(p, &end);
1774	if ((end == p) || (*end != 0)) {
1775	    goto badIndex;
1776	}
1777	bestDist = 1.0e36;
1778	coordPtr = linePtr->coordPtr;
1779	*indexPtr = 0;
1780	for(i=0; i<linePtr->numPoints; i++) {
1781	    dist = hypot(coordPtr[0] - x, coordPtr[1] - y);
1782	    if (dist<bestDist) {
1783		bestDist = dist;
1784		*indexPtr = 2*i;
1785	    }
1786	    coordPtr += 2;
1787	}
1788    } else {
1789	if (Tcl_GetIntFromObj(interp, obj, indexPtr) != TCL_OK) {
1790	    goto badIndex;
1791	}
1792	*indexPtr &= -2;		/* if index is odd, make it even */
1793	if (*indexPtr < 0){
1794	    *indexPtr = 0;
1795	} else if (*indexPtr > (2*linePtr->numPoints)) {
1796	    *indexPtr = (2*linePtr->numPoints);
1797	}
1798    }
1799    return TCL_OK;
1800}
1801
1802/*
1803 *--------------------------------------------------------------
1804 *
1805 * TranslateLine --
1806 *
1807 *	This function is called to move a line by a given amount.
1808 *
1809 * Results:
1810 *	None.
1811 *
1812 * Side effects:
1813 *	The position of the line is offset by (xDelta, yDelta), and the
1814 *	bounding box is updated in the generic part of the item structure.
1815 *
1816 *--------------------------------------------------------------
1817 */
1818
1819static void
1820TranslateLine(
1821    Tk_Canvas canvas,		/* Canvas containing item. */
1822    Tk_Item *itemPtr,		/* Item that is being moved. */
1823    double deltaX, double deltaY)
1824				/* Amount by which item is to be moved. */
1825{
1826    LineItem *linePtr = (LineItem *) itemPtr;
1827    double *coordPtr;
1828    int i;
1829
1830    for (i = 0, coordPtr = linePtr->coordPtr; i < linePtr->numPoints;
1831	    i++, coordPtr += 2) {
1832	coordPtr[0] += deltaX;
1833	coordPtr[1] += deltaY;
1834    }
1835    if (linePtr->firstArrowPtr != NULL) {
1836	for (i = 0, coordPtr = linePtr->firstArrowPtr; i < PTS_IN_ARROW;
1837		i++, coordPtr += 2) {
1838	    coordPtr[0] += deltaX;
1839	    coordPtr[1] += deltaY;
1840	}
1841    }
1842    if (linePtr->lastArrowPtr != NULL) {
1843	for (i = 0, coordPtr = linePtr->lastArrowPtr; i < PTS_IN_ARROW;
1844		i++, coordPtr += 2) {
1845	    coordPtr[0] += deltaX;
1846	    coordPtr[1] += deltaY;
1847	}
1848    }
1849    ComputeLineBbox(canvas, linePtr);
1850}
1851
1852/*
1853 *--------------------------------------------------------------
1854 *
1855 * ParseArrowShape --
1856 *
1857 *	This function is called back during option parsing to parse arrow
1858 *	shape information.
1859 *
1860 * Results:
1861 *	The return value is a standard Tcl result: TCL_OK means that the arrow
1862 *	shape information was parsed ok, and TCL_ERROR means it couldn't be
1863 *	parsed.
1864 *
1865 * Side effects:
1866 *	Arrow information in recordPtr is updated.
1867 *
1868 *--------------------------------------------------------------
1869 */
1870
1871	/* ARGSUSED */
1872static int
1873ParseArrowShape(
1874    ClientData clientData,	/* Not used. */
1875    Tcl_Interp *interp,		/* Used for error reporting. */
1876    Tk_Window tkwin,		/* Not used. */
1877    CONST char *value,		/* Textual specification of arrow shape. */
1878    char *recordPtr,		/* Pointer to item record in which to store
1879				 * arrow information. */
1880    int offset)			/* Offset of shape information in widget
1881				 * record. */
1882{
1883    LineItem *linePtr = (LineItem *) recordPtr;
1884    double a, b, c;
1885    int argc;
1886    CONST char **argv = NULL;
1887
1888    if (offset != Tk_Offset(LineItem, arrowShapeA)) {
1889	Tcl_Panic("ParseArrowShape received bogus offset");
1890    }
1891
1892    if (Tcl_SplitList(interp, (char *) value, &argc, &argv) != TCL_OK) {
1893	syntaxError:
1894	Tcl_ResetResult(interp);
1895	Tcl_AppendResult(interp, "bad arrow shape \"", value,
1896		"\": must be list with three numbers", NULL);
1897	if (argv != NULL) {
1898	    ckfree((char *) argv);
1899	}
1900	return TCL_ERROR;
1901    }
1902    if (argc != 3) {
1903	goto syntaxError;
1904    }
1905    if ((Tk_CanvasGetCoord(interp, linePtr->canvas, argv[0], &a) != TCL_OK)
1906	    || (Tk_CanvasGetCoord(interp, linePtr->canvas, argv[1], &b)
1907		!= TCL_OK)
1908	    || (Tk_CanvasGetCoord(interp, linePtr->canvas, argv[2], &c)
1909		!= TCL_OK)) {
1910	goto syntaxError;
1911    }
1912    linePtr->arrowShapeA = (float)a;
1913    linePtr->arrowShapeB = (float)b;
1914    linePtr->arrowShapeC = (float)c;
1915    ckfree((char *) argv);
1916    return TCL_OK;
1917}
1918
1919/*
1920 *--------------------------------------------------------------
1921 *
1922 * PrintArrowShape --
1923 *
1924 *	This function is a callback invoked by the configuration code to
1925 *	return a printable value describing an arrow shape.
1926 *
1927 * Results:
1928 *	None.
1929 *
1930 * Side effects:
1931 *	None.
1932 *
1933 *--------------------------------------------------------------
1934 */
1935
1936    /* ARGSUSED */
1937static char *
1938PrintArrowShape(
1939    ClientData clientData,	/* Not used. */
1940    Tk_Window tkwin,		/* Window associated with linePtr's widget. */
1941    char *recordPtr,		/* Pointer to item record containing current
1942				 * shape information. */
1943    int offset,			/* Offset of arrow information in record. */
1944    Tcl_FreeProc **freeProcPtr)	/* Store address of function to call to free
1945				 * string here. */
1946{
1947    LineItem *linePtr = (LineItem *) recordPtr;
1948    char *buffer;
1949
1950    buffer = (char *) ckalloc(120);
1951    sprintf(buffer, "%.5g %.5g %.5g", linePtr->arrowShapeA,
1952	    linePtr->arrowShapeB, linePtr->arrowShapeC);
1953    *freeProcPtr = TCL_DYNAMIC;
1954    return buffer;
1955}
1956
1957
1958/*
1959 *--------------------------------------------------------------
1960 *
1961 * ArrowParseProc --
1962 *
1963 *	This function is invoked during option processing to handle the
1964 *	"-arrow" option.
1965 *
1966 * Results:
1967 *	A standard Tcl return value.
1968 *
1969 * Side effects:
1970 *	The arrow for a given item gets replaced by the arrow indicated in the
1971 *	value argument.
1972 *
1973 *--------------------------------------------------------------
1974 */
1975
1976static int
1977ArrowParseProc(
1978    ClientData clientData,	/* some flags.*/
1979    Tcl_Interp *interp,		/* Used for reporting errors. */
1980    Tk_Window tkwin,		/* Window containing canvas widget. */
1981    CONST char *value,		/* Value of option. */
1982    char *widgRec,		/* Pointer to record for item. */
1983    int offset)			/* Offset into item. */
1984{
1985    int c;
1986    size_t length;
1987
1988    register Arrows *arrowPtr = (Arrows *) (widgRec + offset);
1989
1990    if(value == NULL || *value == 0) {
1991	*arrowPtr = ARROWS_NONE;
1992	return TCL_OK;
1993    }
1994
1995    c = value[0];
1996    length = strlen(value);
1997
1998    if ((c == 'n') && (strncmp(value, "none", length) == 0)) {
1999	*arrowPtr = ARROWS_NONE;
2000	return TCL_OK;
2001    }
2002    if ((c == 'f') && (strncmp(value, "first", length) == 0)) {
2003	*arrowPtr = ARROWS_FIRST;
2004	return TCL_OK;
2005    }
2006    if ((c == 'l') && (strncmp(value, "last", length) == 0)) {
2007	*arrowPtr = ARROWS_LAST;
2008	return TCL_OK;
2009    }
2010    if ((c == 'b') && (strncmp(value, "both", length) == 0)) {
2011	*arrowPtr = ARROWS_BOTH;
2012	return TCL_OK;
2013    }
2014
2015    Tcl_AppendResult(interp, "bad arrow spec \"", value,
2016	    "\": must be none, first, last, or both", NULL);
2017    *arrowPtr = ARROWS_NONE;
2018    return TCL_ERROR;
2019}
2020
2021/*
2022 *--------------------------------------------------------------
2023 *
2024 * ArrowPrintProc --
2025 *
2026 *	This function is invoked by the Tk configuration code to produce a
2027 *	printable string for the "-arrow" configuration option.
2028 *
2029 * Results:
2030 *	The return value is a string describing the arrows for the item
2031 *	referred to by "widgRec". In addition, *freeProcPtr is filled in with
2032 *	the address of a function to call to free the result string when it's
2033 *	no longer needed (or NULL to indicate that the string doesn't need to
2034 *	be freed).
2035 *
2036 * Side effects:
2037 *	None.
2038 *
2039 *--------------------------------------------------------------
2040 */
2041
2042static char *
2043ArrowPrintProc(
2044    ClientData clientData,	/* Ignored. */
2045    Tk_Window tkwin,		/* Window containing canvas widget. */
2046    char *widgRec,		/* Pointer to record for item. */
2047    int offset,			/* Offset into item. */
2048    Tcl_FreeProc **freeProcPtr)	/* Pointer to variable to fill in with
2049				 * information about how to reclaim storage
2050				 * for return string. */
2051{
2052    register Arrows *arrowPtr = (Arrows *) (widgRec + offset);
2053
2054    switch (*arrowPtr) {
2055    case ARROWS_FIRST:
2056	return "first";
2057    case ARROWS_LAST:
2058	return "last";
2059    case ARROWS_BOTH:
2060	return "both";
2061    default:
2062	return "none";
2063    }
2064}
2065
2066/*
2067 *--------------------------------------------------------------
2068 *
2069 * ConfigureArrows --
2070 *
2071 *	If arrowheads have been requested for a line, this function makes
2072 *	arrangements for the arrowheads.
2073 *
2074 * Results:
2075 *	Always returns TCL_OK.
2076 *
2077 * Side effects:
2078 *	Information in linePtr is set up for one or two arrowheads. The
2079 *	firstArrowPtr and lastArrowPtr polygons are allocated and initialized,
2080 *	if need be, and the end points of the line are adjusted so that a
2081 *	thick line doesn't stick out past the arrowheads.
2082 *
2083 *--------------------------------------------------------------
2084 */
2085
2086	/* ARGSUSED */
2087static int
2088ConfigureArrows(
2089    Tk_Canvas canvas,		/* Canvas in which arrows will be displayed
2090				 * (interp and tkwin fields are needed). */
2091    LineItem *linePtr)		/* Item to configure for arrows. */
2092{
2093    double *poly, *coordPtr;
2094    double dx, dy, length, sinTheta, cosTheta, temp;
2095    double fracHeight;		/* Line width as fraction of arrowhead
2096				 * width. */
2097    double backup;		/* Distance to backup end points so the line
2098				 * ends in the middle of the arrowhead. */
2099    double vertX, vertY;	/* Position of arrowhead vertex. */
2100    double shapeA, shapeB, shapeC;
2101				/* Adjusted coordinates (see explanation
2102				 * below). */
2103    double width;
2104    Tk_State state = linePtr->header.state;
2105
2106    if (linePtr->numPoints <2) {
2107	return TCL_OK;
2108    }
2109
2110    if(state == TK_STATE_NULL) {
2111	state = ((TkCanvas *)canvas)->canvas_state;
2112    }
2113
2114    width = linePtr->outline.width;
2115    if (((TkCanvas *)canvas)->currentItemPtr == (Tk_Item *)linePtr) {
2116	if (linePtr->outline.activeWidth>width) {
2117	    width = linePtr->outline.activeWidth;
2118	}
2119    } else if (state==TK_STATE_DISABLED) {
2120	if (linePtr->outline.disabledWidth>0) {
2121	    width = linePtr->outline.disabledWidth;
2122	}
2123    }
2124
2125    /*
2126     * The code below makes a tiny increase in the shape parameters for the
2127     * line. This is a bit of a hack, but it seems to result in displays that
2128     * more closely approximate the specified parameters. Without the
2129     * adjustment, the arrows come out smaller than expected.
2130     */
2131
2132    shapeA = linePtr->arrowShapeA + 0.001;
2133    shapeB = linePtr->arrowShapeB + 0.001;
2134    shapeC = linePtr->arrowShapeC + width/2.0 + 0.001;
2135
2136    /*
2137     * If there's an arrowhead on the first point of the line, compute its
2138     * polygon and adjust the first point of the line so that the line doesn't
2139     * stick out past the leading edge of the arrowhead.
2140     */
2141
2142    fracHeight = (width/2.0)/shapeC;
2143    backup = fracHeight*shapeB + shapeA*(1.0 - fracHeight)/2.0;
2144    if (linePtr->arrow != ARROWS_LAST) {
2145	poly = linePtr->firstArrowPtr;
2146	if (poly == NULL) {
2147	    poly = (double *) ckalloc((unsigned)
2148		    (2*PTS_IN_ARROW*sizeof(double)));
2149	    poly[0] = poly[10] = linePtr->coordPtr[0];
2150	    poly[1] = poly[11] = linePtr->coordPtr[1];
2151	    linePtr->firstArrowPtr = poly;
2152	}
2153	dx = poly[0] - linePtr->coordPtr[2];
2154	dy = poly[1] - linePtr->coordPtr[3];
2155	length = hypot(dx, dy);
2156	if (length == 0) {
2157	    sinTheta = cosTheta = 0.0;
2158	} else {
2159	    sinTheta = dy/length;
2160	    cosTheta = dx/length;
2161	}
2162	vertX = poly[0] - shapeA*cosTheta;
2163	vertY = poly[1] - shapeA*sinTheta;
2164	temp = shapeC*sinTheta;
2165	poly[2] = poly[0] - shapeB*cosTheta + temp;
2166	poly[8] = poly[2] - 2*temp;
2167	temp = shapeC*cosTheta;
2168	poly[3] = poly[1] - shapeB*sinTheta - temp;
2169	poly[9] = poly[3] + 2*temp;
2170	poly[4] = poly[2]*fracHeight + vertX*(1.0-fracHeight);
2171	poly[5] = poly[3]*fracHeight + vertY*(1.0-fracHeight);
2172	poly[6] = poly[8]*fracHeight + vertX*(1.0-fracHeight);
2173	poly[7] = poly[9]*fracHeight + vertY*(1.0-fracHeight);
2174
2175	/*
2176	 * Polygon done. Now move the first point towards the second so that
2177	 * the corners at the end of the line are inside the arrowhead.
2178	 */
2179
2180	linePtr->coordPtr[0] = poly[0] - backup*cosTheta;
2181	linePtr->coordPtr[1] = poly[1] - backup*sinTheta;
2182    }
2183
2184    /*
2185     * Similar arrowhead calculation for the last point of the line.
2186     */
2187
2188    if (linePtr->arrow != ARROWS_FIRST) {
2189	coordPtr = linePtr->coordPtr + 2*(linePtr->numPoints-2);
2190	poly = linePtr->lastArrowPtr;
2191	if (poly == NULL) {
2192	    poly = (double *)
2193		    ckalloc((unsigned) (2*PTS_IN_ARROW*sizeof(double)));
2194	    poly[0] = poly[10] = coordPtr[2];
2195	    poly[1] = poly[11] = coordPtr[3];
2196	    linePtr->lastArrowPtr = poly;
2197	}
2198	dx = poly[0] - coordPtr[0];
2199	dy = poly[1] - coordPtr[1];
2200	length = hypot(dx, dy);
2201	if (length == 0) {
2202	    sinTheta = cosTheta = 0.0;
2203	} else {
2204	    sinTheta = dy/length;
2205	    cosTheta = dx/length;
2206	}
2207	vertX = poly[0] - shapeA*cosTheta;
2208	vertY = poly[1] - shapeA*sinTheta;
2209	temp = shapeC * sinTheta;
2210	poly[2] = poly[0] - shapeB*cosTheta + temp;
2211	poly[8] = poly[2] - 2*temp;
2212	temp = shapeC * cosTheta;
2213	poly[3] = poly[1] - shapeB*sinTheta - temp;
2214	poly[9] = poly[3] + 2*temp;
2215	poly[4] = poly[2]*fracHeight + vertX*(1.0-fracHeight);
2216	poly[5] = poly[3]*fracHeight + vertY*(1.0-fracHeight);
2217	poly[6] = poly[8]*fracHeight + vertX*(1.0-fracHeight);
2218	poly[7] = poly[9]*fracHeight + vertY*(1.0-fracHeight);
2219	coordPtr[2] = poly[0] - backup*cosTheta;
2220	coordPtr[3] = poly[1] - backup*sinTheta;
2221    }
2222
2223    return TCL_OK;
2224}
2225
2226/*
2227 *--------------------------------------------------------------
2228 *
2229 * LineToPostscript --
2230 *
2231 *	This function is called to generate Postscript for line items.
2232 *
2233 * Results:
2234 *	The return value is a standard Tcl result. If an error occurs in
2235 *	generating Postscript then an error message is left in the interp's
2236 *	result, replacing whatever used to be there. If no error occurs, then
2237 *	Postscript for the item is appended to the result.
2238 *
2239 * Side effects:
2240 *	None.
2241 *
2242 *--------------------------------------------------------------
2243 */
2244
2245static int
2246LineToPostscript(
2247    Tcl_Interp *interp,		/* Leave Postscript or error message here. */
2248    Tk_Canvas canvas,		/* Information about overall canvas. */
2249    Tk_Item *itemPtr,		/* Item for which Postscript is wanted. */
2250    int prepass)		/* 1 means this is a prepass to collect font
2251				 * information; 0 means final Postscript is
2252				 * being created. */
2253{
2254    LineItem *linePtr = (LineItem *) itemPtr;
2255    char buffer[64 + TCL_INTEGER_SPACE];
2256    char *style;
2257
2258    double width;
2259    XColor *color;
2260    Pixmap stipple;
2261    Tk_State state = itemPtr->state;
2262
2263    if(state == TK_STATE_NULL) {
2264	state = ((TkCanvas *)canvas)->canvas_state;
2265    }
2266
2267    width = linePtr->outline.width;
2268    color = linePtr->outline.color;
2269    stipple = linePtr->outline.stipple;
2270    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
2271	if (linePtr->outline.activeWidth>width) {
2272	    width = linePtr->outline.activeWidth;
2273	}
2274	if (linePtr->outline.activeColor!=NULL) {
2275	    color = linePtr->outline.activeColor;
2276	}
2277	if (linePtr->outline.activeStipple!=None) {
2278	    stipple = linePtr->outline.activeStipple;
2279	}
2280    } else if (state==TK_STATE_DISABLED) {
2281	if (linePtr->outline.disabledWidth>0) {
2282	    width = linePtr->outline.disabledWidth;
2283	}
2284	if (linePtr->outline.disabledColor!=NULL) {
2285	    color = linePtr->outline.disabledColor;
2286	}
2287	if (linePtr->outline.disabledStipple!=None) {
2288	    stipple = linePtr->outline.disabledStipple;
2289	}
2290    }
2291
2292    if (color == NULL || linePtr->numPoints<1 || linePtr->coordPtr==NULL) {
2293	return TCL_OK;
2294    }
2295
2296    if (linePtr->numPoints==1) {
2297	sprintf(buffer, "%.15g %.15g translate %.15g %.15g",
2298		linePtr->coordPtr[0], Tk_CanvasPsY(canvas, linePtr->coordPtr[1]),
2299		width/2.0, width/2.0);
2300	Tcl_AppendResult(interp, "matrix currentmatrix\n",buffer,
2301		" scale 1 0 moveto 0 0 1 0 360 arc\nsetmatrix\n", NULL);
2302	if (Tk_CanvasPsColor(interp, canvas, color) != TCL_OK) {
2303	    return TCL_ERROR;
2304	}
2305	if (stipple != None) {
2306	    Tcl_AppendResult(interp, "clip ", NULL);
2307	    if (Tk_CanvasPsStipple(interp, canvas, stipple) != TCL_OK) {
2308		return TCL_ERROR;
2309	    }
2310	} else {
2311	    Tcl_AppendResult(interp, "fill\n", NULL);
2312	}
2313	return TCL_OK;
2314    }
2315    /*
2316     * Generate a path for the line's center-line (do this differently for
2317     * straight lines and smoothed lines).
2318     */
2319
2320    if ((!linePtr->smooth) || (linePtr->numPoints < 3)) {
2321	Tk_CanvasPsPath(interp, canvas, linePtr->coordPtr, linePtr->numPoints);
2322    } else {
2323	if ((stipple == None) && linePtr->smooth->postscriptProc) {
2324	    linePtr->smooth->postscriptProc(interp, canvas,
2325		    linePtr->coordPtr, linePtr->numPoints, linePtr->splineSteps);
2326	} else {
2327	    /*
2328	     * Special hack: Postscript printers don't appear to be able to
2329	     * turn a path drawn with "curveto"s into a clipping path without
2330	     * exceeding resource limits, so TkMakeBezierPostscript won't work
2331	     * for stippled curves. Instead, generate all of the intermediate
2332	     * points here and output them into the Postscript file with
2333	     * "lineto"s instead.
2334	     */
2335
2336	    double staticPoints[2*MAX_STATIC_POINTS];
2337	    double *pointPtr;
2338	    int numPoints;
2339
2340	    numPoints = linePtr->smooth->coordProc(canvas, NULL,
2341		    linePtr->numPoints, linePtr->splineSteps, NULL, NULL);
2342	    pointPtr = staticPoints;
2343	    if (numPoints > MAX_STATIC_POINTS) {
2344		pointPtr = (double *) ckalloc((unsigned)
2345			(numPoints * 2 * sizeof(double)));
2346	    }
2347	    numPoints = linePtr->smooth->coordProc(canvas, linePtr->coordPtr,
2348		    linePtr->numPoints, linePtr->splineSteps, NULL, pointPtr);
2349	    Tk_CanvasPsPath(interp, canvas, pointPtr, numPoints);
2350	    if (pointPtr != staticPoints) {
2351		ckfree((char *) pointPtr);
2352	    }
2353	}
2354    }
2355
2356    /*
2357     * Set other line-drawing parameters and stroke out the line.
2358     */
2359
2360    style = "0 setlinecap\n";
2361    if (linePtr->capStyle == CapRound) {
2362	style = "1 setlinecap\n";
2363    } else if (linePtr->capStyle == CapProjecting) {
2364	style = "2 setlinecap\n";
2365    }
2366    Tcl_AppendResult(interp, style, NULL);
2367    style = "0 setlinejoin\n";
2368    if (linePtr->joinStyle == JoinRound) {
2369	style = "1 setlinejoin\n";
2370    } else if (linePtr->joinStyle == JoinBevel) {
2371	style = "2 setlinejoin\n";
2372    }
2373    Tcl_AppendResult(interp, style, NULL);
2374
2375    if (Tk_CanvasPsOutline(canvas, itemPtr, &(linePtr->outline)) != TCL_OK) {
2376	return TCL_ERROR;
2377    }
2378
2379    /*
2380     * Output polygons for the arrowheads, if there are any.
2381     */
2382
2383    if (linePtr->firstArrowPtr != NULL) {
2384	if (stipple != None) {
2385	    Tcl_AppendResult(interp, "grestore gsave\n", NULL);
2386	}
2387	if (ArrowheadPostscript(interp, canvas, linePtr,
2388		linePtr->firstArrowPtr) != TCL_OK) {
2389	    return TCL_ERROR;
2390	}
2391    }
2392    if (linePtr->lastArrowPtr != NULL) {
2393	if (stipple != None) {
2394	    Tcl_AppendResult(interp, "grestore gsave\n", NULL);
2395	}
2396	if (ArrowheadPostscript(interp, canvas, linePtr,
2397		linePtr->lastArrowPtr) != TCL_OK) {
2398	    return TCL_ERROR;
2399	}
2400    }
2401    return TCL_OK;
2402}
2403
2404/*
2405 *--------------------------------------------------------------
2406 *
2407 * ArrowheadPostscript --
2408 *
2409 *	This function is called to generate Postscript for an arrowhead for a
2410 *	line item.
2411 *
2412 * Results:
2413 *	The return value is a standard Tcl result. If an error occurs in
2414 *	generating Postscript then an error message is left in the interp's
2415 *	result, replacing whatever used to be there. If no error occurs, then
2416 *	Postscript for the arrowhead is appended to the result.
2417 *
2418 * Side effects:
2419 *	None.
2420 *
2421 *--------------------------------------------------------------
2422 */
2423
2424static int
2425ArrowheadPostscript(
2426    Tcl_Interp *interp,		/* Leave Postscript or error message here. */
2427    Tk_Canvas canvas,		/* Information about overall canvas. */
2428    LineItem *linePtr,		/* Line item for which Postscript is being
2429				 * generated. */
2430    double *arrowPtr)		/* Pointer to first of five points describing
2431				 * arrowhead polygon. */
2432{
2433    Pixmap stipple;
2434    Tk_State state = linePtr->header.state;
2435
2436    if(state == TK_STATE_NULL) {
2437	state = ((TkCanvas *)canvas)->canvas_state;
2438    }
2439
2440    stipple = linePtr->outline.stipple;
2441    if (((TkCanvas *)canvas)->currentItemPtr == (Tk_Item *)linePtr) {
2442	if (linePtr->outline.activeStipple!=None) {
2443	    stipple = linePtr->outline.activeStipple;
2444	}
2445    } else if (state==TK_STATE_DISABLED) {
2446	if (linePtr->outline.activeStipple!=None) {
2447	    stipple = linePtr->outline.disabledStipple;
2448	}
2449    }
2450
2451    Tk_CanvasPsPath(interp, canvas, arrowPtr, PTS_IN_ARROW);
2452    if (stipple != None) {
2453	Tcl_AppendResult(interp, "clip ", NULL);
2454	if (Tk_CanvasPsStipple(interp, canvas, stipple) != TCL_OK) {
2455	    return TCL_ERROR;
2456	}
2457    } else {
2458	Tcl_AppendResult(interp, "fill\n", NULL);
2459    }
2460    return TCL_OK;
2461}
2462
2463/*
2464 * Local Variables:
2465 * mode: c
2466 * c-basic-offset: 4
2467 * fill-column: 78
2468 * End:
2469 */
2470