/* 
 * tkCanvPoly.c --
 *
 *	This file implements polygon items for canvas widgets.
 *
 * Copyright (c) 1991-1994 The Regents of the University of California.
 * Copyright (c) 1994-1997 Sun Microsystems, Inc.
 * Copyright (c) 1998-2000 Ajuba Solutions.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tkCanvPoly.c,v 1.10.2.1 2003/05/11 00:57:09 hobbs Exp $
 */

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

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

typedef struct PolygonItem  {
    Tk_Item header;		/* Generic stuff that's the same for all
				 * types.  MUST BE FIRST IN STRUCTURE. */
    Tk_Outline outline;		/* Outline structure */
    int numPoints;		/* Number of points in polygon.
				 * Polygon is always closed. */
    int pointsAllocated;	/* Number of points for which space is
				 * allocated at *coordPtr. */
    double *coordPtr;		/* Pointer to malloc-ed array containing
				 * x- and y-coords of all points in polygon.
				 * X-coords are even-valued indices, y-coords
				 * are corresponding odd-valued indices. */
    int joinStyle;		/* Join style for outline */
    Tk_TSOffset tsoffset;
    XColor *fillColor;		/* Foreground color for polygon. */
    XColor *activeFillColor;	/* Foreground color for polygon if state is active. */
    XColor *disabledFillColor;	/* Foreground color for polygon if state is disabled. */
    Pixmap fillStipple;		/* Stipple bitmap for filling polygon. */
    Pixmap activeFillStipple;	/* Stipple bitmap for filling polygon if state is active. */
    Pixmap disabledFillStipple;	/* Stipple bitmap for filling polygon if state is disabled. */
    GC fillGC;			/* Graphics context for filling polygon. */
    Tk_SmoothMethod *smooth;	/* Non-zero means draw shape smoothed (i.e.
				 * with Bezier splines). */
    int splineSteps;		/* Number of steps in each spline segment. */
    int autoClosed;		/* Zero means the given polygon was closed,
				   one means that we auto closed it. */
} PolygonItem;

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

static Tk_CustomOption smoothOption = {
    (Tk_OptionParseProc *) TkSmoothParseProc,
    TkSmoothPrintProc, (ClientData) NULL
};
static Tk_CustomOption stateOption = {
    (Tk_OptionParseProc *) TkStateParseProc,
    TkStatePrintProc, (ClientData) 2
};
static Tk_CustomOption tagsOption = {
    (Tk_OptionParseProc *) Tk_CanvasTagsParseProc,
    Tk_CanvasTagsPrintProc, (ClientData) NULL
};
static Tk_CustomOption dashOption = {
    (Tk_OptionParseProc *) TkCanvasDashParseProc,
    TkCanvasDashPrintProc, (ClientData) NULL
};
static Tk_CustomOption offsetOption = {
    (Tk_OptionParseProc *) TkOffsetParseProc,
    TkOffsetPrintProc,
    (ClientData) (TK_OFFSET_RELATIVE|TK_OFFSET_INDEX)
};
static Tk_CustomOption pixelOption = {
    (Tk_OptionParseProc *) TkPixelParseProc,
    TkPixelPrintProc, (ClientData) NULL
};

static Tk_ConfigSpec configSpecs[] = {
    {TK_CONFIG_CUSTOM, "-activedash", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.activeDash),
	TK_CONFIG_NULL_OK, &dashOption},
    {TK_CONFIG_COLOR, "-activefill", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, activeFillColor),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-activeoutline", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.activeColor),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-activeoutlinestipple", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.activeStipple),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-activestipple", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, activeFillStipple),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_CUSTOM, "-activewidth", (char *) NULL, (char *) NULL,
	"0.0", Tk_Offset(PolygonItem, outline.activeWidth),
	TK_CONFIG_DONT_SET_DEFAULT, &pixelOption},
    {TK_CONFIG_CUSTOM, "-dash", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.dash),
	TK_CONFIG_NULL_OK, &dashOption},
    {TK_CONFIG_PIXELS, "-dashoffset", (char *) NULL, (char *) NULL,
	"0", Tk_Offset(PolygonItem, outline.offset),
	TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_CUSTOM, "-disableddash", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.disabledDash),
	TK_CONFIG_NULL_OK, &dashOption},
    {TK_CONFIG_COLOR, "-disabledfill", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, disabledFillColor),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-disabledoutline", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.disabledColor),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-disabledoutlinestipple", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.disabledStipple),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-disabledstipple", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, disabledFillStipple),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_CUSTOM, "-disabledwidth", (char *) NULL, (char *) NULL,
	"0.0", Tk_Offset(PolygonItem, outline.disabledWidth),
	TK_CONFIG_DONT_SET_DEFAULT, &pixelOption},
    {TK_CONFIG_COLOR, "-fill", (char *) NULL, (char *) NULL,
	"black", Tk_Offset(PolygonItem, fillColor), TK_CONFIG_NULL_OK},
    {TK_CONFIG_JOIN_STYLE, "-joinstyle", (char *) NULL, (char *) NULL,
	"round", Tk_Offset(PolygonItem, joinStyle), TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_CUSTOM, "-offset", (char *) NULL, (char *) NULL,
	"0,0", Tk_Offset(PolygonItem, tsoffset),
	TK_CONFIG_NULL_OK, &offsetOption},
    {TK_CONFIG_COLOR, "-outline", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.color),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_CUSTOM, "-outlineoffset", (char *) NULL, (char *) NULL,
	"0,0", Tk_Offset(PolygonItem, outline.tsoffset),
	TK_CONFIG_NULL_OK, &offsetOption},
    {TK_CONFIG_BITMAP, "-outlinestipple", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, outline.stipple),
	TK_CONFIG_NULL_OK},
    {TK_CONFIG_CUSTOM, "-smooth", (char *) NULL, (char *) NULL,
	"0", Tk_Offset(PolygonItem, smooth),
	TK_CONFIG_DONT_SET_DEFAULT, &smoothOption},
    {TK_CONFIG_INT, "-splinesteps", (char *) NULL, (char *) NULL,
	"12", Tk_Offset(PolygonItem, splineSteps), TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_CUSTOM, "-state", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(Tk_Item, state), TK_CONFIG_NULL_OK,
	&stateOption},
    {TK_CONFIG_BITMAP, "-stipple", (char *) NULL, (char *) NULL,
	(char *) NULL, Tk_Offset(PolygonItem, fillStipple), TK_CONFIG_NULL_OK},
    {TK_CONFIG_CUSTOM, "-tags", (char *) NULL, (char *) NULL,
	(char *) NULL, 0, TK_CONFIG_NULL_OK, &tagsOption},
    {TK_CONFIG_CUSTOM, "-width", (char *) NULL, (char *) NULL,
	"1.0", Tk_Offset(PolygonItem, outline.width),
	TK_CONFIG_DONT_SET_DEFAULT, &pixelOption},
    {TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
	(char *) NULL, 0, 0}
};

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

static void		ComputePolygonBbox _ANSI_ARGS_((Tk_Canvas canvas,
			    PolygonItem *polyPtr));
static int		ConfigurePolygon _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr, int objc,
			    Tcl_Obj *CONST objv[], int flags));
static int		CreatePolygon _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, struct Tk_Item *itemPtr,
			    int objc, Tcl_Obj *CONST objv[]));
static void		DeletePolygon _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr,  Display *display));
static void		DisplayPolygon _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, Display *display, Drawable dst,
			    int x, int y, int width, int height));
static int		GetPolygonIndex _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr,
			    Tcl_Obj *obj, int *indexPtr));
static int		PolygonCoords _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr,
			    int objc, Tcl_Obj *CONST objv[]));
static void		PolygonDeleteCoords _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, int first, int last));
static void		PolygonInsert _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, int beforeThis, Tcl_Obj *obj));
static int		PolygonToArea _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double *rectPtr));
static double		PolygonToPoint _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double *pointPtr));
static int		PolygonToPostscript _ANSI_ARGS_((Tcl_Interp *interp,
			    Tk_Canvas canvas, Tk_Item *itemPtr, int prepass));
static void		ScalePolygon _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double originX, double originY,
			    double scaleX, double scaleY));
static void		TranslatePolygon _ANSI_ARGS_((Tk_Canvas canvas,
			    Tk_Item *itemPtr, double deltaX, double deltaY));

/*
 * The structures below defines the polygon item type by means
 * of procedures that can be invoked by generic item code.
 */

Tk_ItemType tkPolygonType = {
    "polygon",				/* name */
    sizeof(PolygonItem),		/* itemSize */
    CreatePolygon,			/* createProc */
    configSpecs,			/* configSpecs */
    ConfigurePolygon,			/* configureProc */
    PolygonCoords,			/* coordProc */
    DeletePolygon,			/* deleteProc */
    DisplayPolygon,			/* displayProc */
    TK_CONFIG_OBJS,			/* flags */
    PolygonToPoint,			/* pointProc */
    PolygonToArea,			/* areaProc */
    PolygonToPostscript,		/* postscriptProc */
    ScalePolygon,			/* scaleProc */
    TranslatePolygon,			/* translateProc */
    (Tk_ItemIndexProc *) GetPolygonIndex,/* indexProc */
    (Tk_ItemCursorProc *) NULL,		/* icursorProc */
    (Tk_ItemSelectionProc *) NULL,	/* selectionProc */
    (Tk_ItemInsertProc *) PolygonInsert,/* insertProc */
    PolygonDeleteCoords,		/* dTextProc */
    (Tk_ItemType *) NULL,		/* nextPtr */
};

/*
 * The definition below determines how large are static arrays
 * used to hold spline points (splines larger than this have to
 * have their arrays malloc-ed).
 */

#define MAX_STATIC_POINTS 200

/*
 *--------------------------------------------------------------
 *
 * CreatePolygon --
 *
 *	This procedure is invoked to create a new polygon 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
 *	the interp's result;  in this case itemPtr is
 *	left uninitialized, so it can be safely freed by the
 *	caller.
 *
 * Side effects:
 *	A new polygon item is created.
 *
 *--------------------------------------------------------------
 */

static int
CreatePolygon(interp, canvas, itemPtr, objc, objv)
    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 objc;				/* Number of arguments in objv. */
    Tcl_Obj *CONST objv[];		/* Arguments describing polygon. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    int i;

    if (objc == 0) {
	panic("canvas did not pass any coords\n");
    }

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

    Tk_CreateOutline(&(polyPtr->outline));
    polyPtr->numPoints = 0;
    polyPtr->pointsAllocated = 0;
    polyPtr->coordPtr = NULL;
    polyPtr->joinStyle = JoinRound;
    polyPtr->tsoffset.flags = 0;
    polyPtr->tsoffset.xoffset = 0;
    polyPtr->tsoffset.yoffset = 0;
    polyPtr->fillColor = NULL;
    polyPtr->activeFillColor = NULL;
    polyPtr->disabledFillColor = NULL;
    polyPtr->fillStipple = None;
    polyPtr->activeFillStipple = None;
    polyPtr->disabledFillStipple = None;
    polyPtr->fillGC = None;
    polyPtr->smooth = (Tk_SmoothMethod *) NULL;
    polyPtr->splineSteps = 12;
    polyPtr->autoClosed = 0;

    /*
     * Count the number of points and then parse them into a point
     * array.  Leading arguments are assumed to be points if they
     * start with a digit or a minus sign followed by a digit.
     */

    for (i = 0; i < objc; i++) {
	char *arg = Tcl_GetString(objv[i]);
	if ((arg[0] == '-') && (arg[1] >= 'a') && (arg[1] <= 'z')) {
	    break;
	}
    }
    if (i && PolygonCoords(interp, canvas, itemPtr, i, objv) != TCL_OK) {
	goto error;
    }

    if (ConfigurePolygon(interp, canvas, itemPtr, objc-i, objv+i, 0)
	    == TCL_OK) {
	return TCL_OK;
    }

    error:
    DeletePolygon(canvas, itemPtr, Tk_Display(Tk_CanvasTkwin(canvas)));
    return TCL_ERROR;
}

/*
 *--------------------------------------------------------------
 *
 * PolygonCoords --
 *
 *	This procedure is invoked to process the "coords" widget
 *	command on polygons.  See the user documentation for details
 *	on what it does.
 *
 * Results:
 *	Returns TCL_OK or TCL_ERROR, and sets the interp's result.
 *
 * Side effects:
 *	The coordinates for the given item may be changed.
 *
 *--------------------------------------------------------------
 */

static int
PolygonCoords(interp, canvas, itemPtr, objc, objv)
    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 objc;				/* Number of coordinates supplied in
					 * objv. */
    Tcl_Obj *CONST objv[];		/* Array of coordinates: x1, y1,
					 * x2, y2, ... */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    int i, numPoints;

    if (objc == 0) {
	/*
	 * Print the coords used to create the polygon.  If we auto
	 * closed the polygon then we don't report the last point.
	 */
	Tcl_Obj *subobj, *obj = Tcl_NewObj();
	for (i = 0; i < 2*(polyPtr->numPoints - polyPtr->autoClosed); i++) {
	    subobj = Tcl_NewDoubleObj(polyPtr->coordPtr[i]);
	    Tcl_ListObjAppendElement(interp, obj, subobj);
	}
	Tcl_SetObjResult(interp, obj);
	return TCL_OK;
    }
    if (objc == 1) {
	if (Tcl_ListObjGetElements(interp, objv[0], &objc,
		(Tcl_Obj ***) &objv) != TCL_OK) {
	    return TCL_ERROR;
	}
    }
    if (objc & 1) {
	char buf[64 + TCL_INTEGER_SPACE];
	sprintf(buf, "wrong # coordinates: expected an even number, got %d",
		objc);
	Tcl_SetResult(interp, buf, TCL_VOLATILE);
	return TCL_ERROR;
    } else {
	numPoints = objc/2;
	if (polyPtr->pointsAllocated <= numPoints) {
	    if (polyPtr->coordPtr != NULL) {
		ckfree((char *) polyPtr->coordPtr);
	    }

	    /*
	     * One extra point gets allocated here, because we always
	     * add another point to close the polygon.
	     */

	    polyPtr->coordPtr = (double *) ckalloc((unsigned)
		    (sizeof(double) * (objc+2)));
	    polyPtr->pointsAllocated = numPoints+1;
	}
	for (i = objc-1; i >= 0; i--) {
	    if (Tk_CanvasGetCoordFromObj(interp, canvas, objv[i],
		    &polyPtr->coordPtr[i]) != TCL_OK) {
		return TCL_ERROR;
	    }
	}
	polyPtr->numPoints = numPoints;
	polyPtr->autoClosed = 0;

	/*
	 * Close the polygon if it isn't already closed.
	 */
    
	if (objc>2 && ((polyPtr->coordPtr[objc-2] != polyPtr->coordPtr[0])
		|| (polyPtr->coordPtr[objc-1] != polyPtr->coordPtr[1]))) {
	    polyPtr->autoClosed = 1;
	    polyPtr->numPoints++;
	    polyPtr->coordPtr[objc] = polyPtr->coordPtr[0];
	    polyPtr->coordPtr[objc+1] = polyPtr->coordPtr[1];
	}
	ComputePolygonBbox(canvas, polyPtr);
    }
    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * ConfigurePolygon --
 *
 *	This procedure is invoked to configure various aspects
 *	of a polygon item such as its background color.
 *
 * Results:
 *	A standard Tcl result code.  If an error occurs, then
 *	an error message is left in the interp's result.
 *
 * Side effects:
 *	Configuration information, such as colors and stipple
 *	patterns, may be set for itemPtr.
 *
 *--------------------------------------------------------------
 */

static int
ConfigurePolygon(interp, canvas, itemPtr, objc, objv, flags)
    Tcl_Interp *interp;		/* Interpreter for error reporting. */
    Tk_Canvas canvas;		/* Canvas containing itemPtr. */
    Tk_Item *itemPtr;		/* Polygon item to reconfigure. */
    int objc;			/* Number of elements in objv.  */
    Tcl_Obj *CONST objv[];	/* Arguments describing things to configure. */
    int flags;			/* Flags to pass to Tk_ConfigureWidget. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    XGCValues gcValues;
    GC newGC;
    unsigned long mask;
    Tk_Window tkwin;
    XColor *color;
    Pixmap stipple;
    Tk_State state;

    tkwin = Tk_CanvasTkwin(canvas);
    if (TCL_OK != Tk_ConfigureWidget(interp, tkwin, configSpecs, objc,
	    (CONST char **) objv, (char *) polyPtr, flags|TK_CONFIG_OBJS)) {
	return TCL_ERROR;
    }

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

    state = itemPtr->state;

    if (polyPtr->outline.activeWidth > polyPtr->outline.width ||
	    polyPtr->outline.activeDash.number != 0 ||
	    polyPtr->outline.activeColor != NULL ||
	    polyPtr->outline.activeStipple != None ||
	    polyPtr->activeFillColor != NULL ||
	    polyPtr->activeFillStipple != None) {
	itemPtr->redraw_flags |= TK_ITEM_STATE_DEPENDANT;
    } else {
	itemPtr->redraw_flags &= ~TK_ITEM_STATE_DEPENDANT;
    }

    if(state == TK_STATE_NULL) {
	state = ((TkCanvas *)canvas)->canvas_state;
    }
    if (state==TK_STATE_HIDDEN) {
	ComputePolygonBbox(canvas, polyPtr);
	return TCL_OK;
    }

    mask = Tk_ConfigOutlineGC(&gcValues, canvas, itemPtr, &(polyPtr->outline));
    if (mask) {
	gcValues.cap_style = CapRound;
	gcValues.join_style = polyPtr->joinStyle;
	mask |= GCCapStyle|GCJoinStyle;
	newGC = Tk_GetGC(tkwin, mask, &gcValues);
    } else {
	newGC = None;
    }
    if (polyPtr->outline.gc != None) {
	Tk_FreeGC(Tk_Display(tkwin), polyPtr->outline.gc);
    }
    polyPtr->outline.gc = newGC;

    color = polyPtr->fillColor;
    stipple = polyPtr->fillStipple;
    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
	if (polyPtr->activeFillColor!=NULL) {
	    color = polyPtr->activeFillColor;
	}
	if (polyPtr->activeFillStipple!=None) {
	    stipple = polyPtr->activeFillStipple;
	}
    } else if (state==TK_STATE_DISABLED) {
	if (polyPtr->disabledFillColor!=NULL) {
	    color = polyPtr->disabledFillColor;
	}
	if (polyPtr->disabledFillStipple!=None) {
	    stipple = polyPtr->disabledFillStipple;
	}
    }

    if (color == NULL) {
	newGC = None;
    } else {
	gcValues.foreground = color->pixel;
	mask = GCForeground;
	if (stipple != None) {
	    gcValues.stipple = stipple;
	    gcValues.fill_style = FillStippled;
	    mask |= GCStipple|GCFillStyle;
	}
	newGC = Tk_GetGC(tkwin, mask, &gcValues);
    }
    if (polyPtr->fillGC != None) {
	Tk_FreeGC(Tk_Display(tkwin), polyPtr->fillGC);
    }
    polyPtr->fillGC = newGC;

    /*
     * Keep spline parameters within reasonable limits.
     */

    if (polyPtr->splineSteps < 1) {
	polyPtr->splineSteps = 1;
    } else if (polyPtr->splineSteps > 100) {
	polyPtr->splineSteps = 100;
    }

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

static void
DeletePolygon(canvas, itemPtr, display)
    Tk_Canvas canvas;			/* Info about overall canvas widget. */
    Tk_Item *itemPtr;			/* Item that is being deleted. */
    Display *display;			/* Display containing window for
					 * canvas. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;

    Tk_DeleteOutline(display,&(polyPtr->outline));
    if (polyPtr->coordPtr != NULL) {
	ckfree((char *) polyPtr->coordPtr);
    }
    if (polyPtr->fillColor != NULL) {
	Tk_FreeColor(polyPtr->fillColor);
    }
    if (polyPtr->activeFillColor != NULL) {
	Tk_FreeColor(polyPtr->activeFillColor);
    }
    if (polyPtr->disabledFillColor != NULL) {
	Tk_FreeColor(polyPtr->disabledFillColor);
    }
    if (polyPtr->fillStipple != None) {
	Tk_FreeBitmap(display, polyPtr->fillStipple);
    }
    if (polyPtr->activeFillStipple != None) {
	Tk_FreeBitmap(display, polyPtr->activeFillStipple);
    }
    if (polyPtr->disabledFillStipple != None) {
	Tk_FreeBitmap(display, polyPtr->disabledFillStipple);
    }
    if (polyPtr->fillGC != None) {
	Tk_FreeGC(display, polyPtr->fillGC);
    }
}

/*
 *--------------------------------------------------------------
 *
 * ComputePolygonBbox --
 *
 *	This procedure is invoked to compute the bounding box of
 *	all the pixels that may be drawn as part of a polygon.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The fields x1, y1, x2, and y2 are updated in the header
 *	for itemPtr.
 *
 *--------------------------------------------------------------
 */

static void
ComputePolygonBbox(canvas, polyPtr)
    Tk_Canvas canvas;			/* Canvas that contains item. */
    PolygonItem *polyPtr;		/* Item whose bbox is to be
					 * recomputed. */
{
    double *coordPtr;
    int i;
    double width;
    Tk_State state = polyPtr->header.state;
    Tk_TSOffset *tsoffset;

    if(state == TK_STATE_NULL) {
	state = ((TkCanvas *)canvas)->canvas_state;
    }
    width = polyPtr->outline.width;
    if (polyPtr->coordPtr == NULL || (polyPtr->numPoints < 1) || (state==TK_STATE_HIDDEN)) {
	polyPtr->header.x1 = polyPtr->header.x2 =
	polyPtr->header.y1 = polyPtr->header.y2 = -1;
	return;
    }
    if (((TkCanvas *)canvas)->currentItemPtr == (Tk_Item *)polyPtr) {
	if (polyPtr->outline.activeWidth>width) {
	    width = polyPtr->outline.activeWidth;
	}
    } else if (state==TK_STATE_DISABLED) {
	if (polyPtr->outline.disabledWidth>0.0) {
	    width = polyPtr->outline.disabledWidth;
	}
    }

    coordPtr = polyPtr->coordPtr;
    polyPtr->header.x1 = polyPtr->header.x2 = (int) *coordPtr;
    polyPtr->header.y1 = polyPtr->header.y2 = (int) coordPtr[1];

    /*
     * Compute the bounding box of all the points in the polygon,
     * then expand in all directions by the outline's width to take
     * care of butting or rounded corners and projecting or
     * rounded caps.  This expansion is an overestimate (worst-case
     * is square root of two over two) but it's simple.  Don't do
     * anything special for curves.  This causes an additional
     * overestimate in the bounding box, but is faster.
     */

    for (i = 1, coordPtr = polyPtr->coordPtr+2; i < polyPtr->numPoints-1;
	    i++, coordPtr += 2) {
	TkIncludePoint((Tk_Item *) polyPtr, coordPtr);
    }

    tsoffset = &polyPtr->tsoffset;
    if (tsoffset->flags & TK_OFFSET_INDEX) {
	int index = tsoffset->flags & ~TK_OFFSET_INDEX;
	if (tsoffset->flags == INT_MAX) {
	    index = (polyPtr->numPoints - polyPtr->autoClosed) * 2;
	    if (index < 0) {
		index = 0;
	    }
	}
	index %= (polyPtr->numPoints - polyPtr->autoClosed) * 2;
	if (index <0) {
	    index += (polyPtr->numPoints - polyPtr->autoClosed) * 2;
	}
 	tsoffset->xoffset = (int) (polyPtr->coordPtr[index] + 0.5);
	tsoffset->yoffset = (int) (polyPtr->coordPtr[index+1] + 0.5);
    } else {
	if (tsoffset->flags & TK_OFFSET_LEFT) {
	    tsoffset->xoffset = polyPtr->header.x1;
	} else if (tsoffset->flags & TK_OFFSET_CENTER) {
	    tsoffset->xoffset = (polyPtr->header.x1 + polyPtr->header.x2)/2;
	} else if (tsoffset->flags & TK_OFFSET_RIGHT) {
	    tsoffset->xoffset = polyPtr->header.x2;
	}
	if (tsoffset->flags & TK_OFFSET_TOP) {
	    tsoffset->yoffset = polyPtr->header.y1;
	} else if (tsoffset->flags & TK_OFFSET_MIDDLE) {
	    tsoffset->yoffset = (polyPtr->header.y1 + polyPtr->header.y2)/2;
	} else if (tsoffset->flags & TK_OFFSET_BOTTOM) {
	    tsoffset->yoffset = polyPtr->header.y2;
	}
    }

    if (polyPtr->outline.gc != None) {
	tsoffset = &polyPtr->outline.tsoffset;
	if (tsoffset) {
	    if (tsoffset->flags & TK_OFFSET_INDEX) {
		int index = tsoffset->flags & ~TK_OFFSET_INDEX;
		if (tsoffset->flags == INT_MAX) {
		    index = (polyPtr->numPoints - 1) * 2;
		}
		index %= (polyPtr->numPoints - 1) * 2;
		if (index <0) {
		    index += (polyPtr->numPoints - 1) * 2;
		}
		tsoffset->xoffset = (int) (polyPtr->coordPtr[index] + 0.5);
		tsoffset->yoffset = (int) (polyPtr->coordPtr[index+1] + 0.5);
	    } else {
		if (tsoffset->flags & TK_OFFSET_LEFT) {
		    tsoffset->xoffset = polyPtr->header.x1;
		} else if (tsoffset->flags & TK_OFFSET_CENTER) {
		    tsoffset->xoffset = (polyPtr->header.x1 + polyPtr->header.x2)/2;
		} else if (tsoffset->flags & TK_OFFSET_RIGHT) {
		    tsoffset->xoffset = polyPtr->header.x2;
		}
		if (tsoffset->flags & TK_OFFSET_TOP) {
		    tsoffset->yoffset = polyPtr->header.y1;
		} else if (tsoffset->flags & TK_OFFSET_MIDDLE) {
		    tsoffset->yoffset = (polyPtr->header.y1 + polyPtr->header.y2)/2;
		} else if (tsoffset->flags & TK_OFFSET_BOTTOM) {
		    tsoffset->yoffset = polyPtr->header.y2;
		}
	    }
	}

	i = (int) ((width+1.5)/2.0);
	polyPtr->header.x1 -= i;
	polyPtr->header.x2 += i;
	polyPtr->header.y1 -= i;
	polyPtr->header.y2 += i;

	/*
	 * For mitered lines, make a second pass through all the points.
	 * Compute the locations of the two miter vertex points and add
	 * those into the bounding box.
	 */

	if (polyPtr->joinStyle == JoinMiter) {
	    double miter[4];
	    int j;
	    coordPtr = polyPtr->coordPtr;
	    if (polyPtr->numPoints>3) {
		if (TkGetMiterPoints(coordPtr+2*(polyPtr->numPoints-2),
			coordPtr, coordPtr+2, width,
			miter, miter+2)) {
		    for (j = 0; j < 4; j += 2) {
			TkIncludePoint((Tk_Item *) polyPtr, miter+j);
		    }
		}
	     }
	    for (i = polyPtr->numPoints ; i >= 3;
		    i--, coordPtr += 2) {
    
		if (TkGetMiterPoints(coordPtr, coordPtr+2, coordPtr+4,
			width, miter, miter+2)) {
		    for (j = 0; j < 4; j += 2) {
			TkIncludePoint((Tk_Item *) polyPtr, miter+j);
		    }
		}
	    }
	}
    }

    /*
     * Add one more pixel of fudge factor just to be safe (e.g.
     * X may round differently than we do).
     */

    polyPtr->header.x1 -= 1;
    polyPtr->header.x2 += 1;
    polyPtr->header.y1 -= 1;
    polyPtr->header.y2 += 1;
}

/*
 *--------------------------------------------------------------
 *
 * TkFillPolygon --
 *
 *	This procedure is invoked to convert a polygon to screen
 *	coordinates and display it using a particular GC.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	ItemPtr is drawn in drawable using the transformation
 *	information in canvas.
 *
 *--------------------------------------------------------------
 */

void
TkFillPolygon(canvas, coordPtr, numPoints, display, drawable, gc, outlineGC)
    Tk_Canvas canvas;			/* Canvas whose coordinate system
					 * is to be used for drawing. */
    double *coordPtr;			/* Array of coordinates for polygon:
					 * x1, y1, x2, y2, .... */
    int numPoints;			/* Twice this many coordinates are
					 * present at *coordPtr. */
    Display *display;			/* Display on which to draw polygon. */
    Drawable drawable;			/* Pixmap or window in which to draw
					 * polygon. */
    GC gc;				/* Graphics context for drawing. */
    GC outlineGC;			/* If not None, use this to draw an
					 * outline around the polygon after
					 * filling it. */
{
    XPoint staticPoints[MAX_STATIC_POINTS];
    XPoint *pointPtr;
    XPoint *pPtr;
    int i;

    /*
     * Build up an array of points in screen coordinates.  Use a
     * static array unless the polygon has an enormous number of points;
     * in this case, dynamically allocate an array.
     */

    if (numPoints <= MAX_STATIC_POINTS) {
	pointPtr = staticPoints;
    } else {
	pointPtr = (XPoint *) ckalloc((unsigned) (numPoints * sizeof(XPoint)));
    }

    for (i = 0, pPtr = pointPtr; i < numPoints; i += 1, coordPtr += 2, pPtr++) {
	Tk_CanvasDrawableCoords(canvas, coordPtr[0], coordPtr[1], &pPtr->x,
		&pPtr->y);
    }

    /*
     * Display polygon, then free up polygon storage if it was dynamically
     * allocated.
     */

    if (gc != None && numPoints>3) {
	XFillPolygon(display, drawable, gc, pointPtr, numPoints, Complex,
		CoordModeOrigin);
    }
    if (outlineGC != None) {
	XDrawLines(display, drawable, outlineGC, pointPtr,
	    numPoints, CoordModeOrigin);
    }
    if (pointPtr != staticPoints) {
	ckfree((char *) pointPtr);
    }
}

/*
 *--------------------------------------------------------------
 *
 * DisplayPolygon --
 *
 *	This procedure is invoked to draw a polygon item in a given
 *	drawable.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	ItemPtr is drawn in drawable using the transformation
 *	information in canvas.
 *
 *--------------------------------------------------------------
 */

static void
DisplayPolygon(canvas, itemPtr, display, drawable, x, y, width, height)
    Tk_Canvas canvas;			/* Canvas that contains item. */
    Tk_Item *itemPtr;			/* Item to be displayed. */
    Display *display;			/* Display on which to draw item. */
    Drawable drawable;			/* Pixmap or window in which to draw
					 * item. */
    int x, y, width, height;		/* Describes region of canvas that
					 * must be redisplayed (not used). */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    Tk_State state = itemPtr->state;
    Pixmap stipple = polyPtr->fillStipple;
    double linewidth = polyPtr->outline.width;

    if (((polyPtr->fillGC == None) && (polyPtr->outline.gc == None)) ||
	    (polyPtr->numPoints < 1) ||
	    (polyPtr->numPoints < 3 && polyPtr->outline.gc == None)) {
	return;
    }

    if(state == TK_STATE_NULL) {
	state = ((TkCanvas *)canvas)->canvas_state;
    }
    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
	if (polyPtr->outline.activeWidth>linewidth) {
	    linewidth = polyPtr->outline.activeWidth;
	}
	if (polyPtr->activeFillStipple != None) {
	    stipple = polyPtr->activeFillStipple;
	}
    } else if (state==TK_STATE_DISABLED) {
	if (polyPtr->outline.disabledWidth>0.0) {
	    linewidth = polyPtr->outline.disabledWidth;
	}
	if (polyPtr->disabledFillStipple != None) {
	    stipple = polyPtr->disabledFillStipple;
	}
    }
    /*
     * If we're stippling then modify the stipple offset in the GC.  Be
     * sure to reset the offset when done, since the GC is supposed to be
     * read-only.
     */

    if ((stipple != None) && (polyPtr->fillGC != None)) {
	Tk_TSOffset *tsoffset = &polyPtr->tsoffset;
	int w=0; int h=0;
	int flags = tsoffset->flags;
	if (!(flags & TK_OFFSET_INDEX) && (flags & (TK_OFFSET_CENTER|TK_OFFSET_MIDDLE))) {
	    Tk_SizeOfBitmap(display, stipple, &w, &h);
	    if (flags & TK_OFFSET_CENTER) {
		w /= 2;
	    } else {
		w = 0;
	    }
	    if (flags & TK_OFFSET_MIDDLE) {
		h /= 2;
	    } else {
		h = 0;
	    }
	}
	tsoffset->xoffset -= w;
	tsoffset->yoffset -= h;
	Tk_CanvasSetOffset(canvas, polyPtr->fillGC, tsoffset);
	tsoffset->xoffset += w;
	tsoffset->yoffset += h;
    }
    Tk_ChangeOutlineGC(canvas, itemPtr, &(polyPtr->outline));

    if(polyPtr->numPoints < 3) {
	short x,y;
	int intLineWidth = (int) (linewidth + 0.5);
	if (intLineWidth < 1) {
	    intLineWidth = 1;
	}
	Tk_CanvasDrawableCoords(canvas, polyPtr->coordPtr[0],
		    polyPtr->coordPtr[1], &x,&y);
	XFillArc(display, drawable, polyPtr->outline.gc,
		x - intLineWidth/2, y - intLineWidth/2,
		(unsigned int)intLineWidth+1, (unsigned int)intLineWidth+1,
		0, 64*360);
    } else if (!polyPtr->smooth || polyPtr->numPoints < 4) {
	TkFillPolygon(canvas, polyPtr->coordPtr, polyPtr->numPoints,
		    display, drawable, polyPtr->fillGC, polyPtr->outline.gc);
    } else {
	int numPoints;
	XPoint staticPoints[MAX_STATIC_POINTS];
	XPoint *pointPtr;

	/*
	 * This is a smoothed polygon.  Display using a set of generated
	 * spline points rather than the original points.
	 */

	numPoints = polyPtr->smooth->coordProc(canvas, (double *) NULL,
		polyPtr->numPoints, polyPtr->splineSteps, (XPoint *) NULL,
		(double *) NULL);
	if (numPoints <= MAX_STATIC_POINTS) {
	    pointPtr = staticPoints;
	} else {
	    pointPtr = (XPoint *) ckalloc((unsigned)
		    (numPoints * sizeof(XPoint)));
	}
	numPoints = polyPtr->smooth->coordProc(canvas, polyPtr->coordPtr,
		polyPtr->numPoints, polyPtr->splineSteps, pointPtr,
		(double *) NULL);
	if (polyPtr->fillGC != None) {
	    XFillPolygon(display, drawable, polyPtr->fillGC, pointPtr,
		    numPoints, Complex, CoordModeOrigin);
	}
	if (polyPtr->outline.gc != None) {
	    XDrawLines(display, drawable, polyPtr->outline.gc, pointPtr,
		    numPoints, CoordModeOrigin);
	}
	if (pointPtr != staticPoints) {
	    ckfree((char *) pointPtr);
	}
    }
    Tk_ResetOutlineGC(canvas, itemPtr, &(polyPtr->outline));
    if ((stipple != None) && (polyPtr->fillGC != None)) {
	XSetTSOrigin(display, polyPtr->fillGC, 0, 0);
    }
}

/*
 *--------------------------------------------------------------
 *
 * PolygonInsert --
 *
 *	Insert coords into a polugon item at a given index.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The coords in the given item is modified.
 *
 *--------------------------------------------------------------
 */

static void
PolygonInsert(canvas, itemPtr, beforeThis, obj)
    Tk_Canvas canvas;		/* Canvas containing text item. */
    Tk_Item *itemPtr;		/* Line item to be modified. */
    int beforeThis;		/* Index before which new coordinates
				 * are to be inserted. */
    Tcl_Obj *obj;		/* New coordinates to be inserted. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    int length, objc, i;
    Tcl_Obj **objv;
    double *new;
    Tk_State state = itemPtr->state;

    if (state == TK_STATE_NULL) {
	state = ((TkCanvas *)canvas)->canvas_state;
    }

    if (!obj || (Tcl_ListObjGetElements((Tcl_Interp *) NULL, obj, &objc, &objv) != TCL_OK)
	    || !objc || objc&1) {
	return;
    }
    length = 2*(polyPtr->numPoints - polyPtr->autoClosed);
    while(beforeThis>length) beforeThis-=length;
    while(beforeThis<0) beforeThis+=length;
    new = (double *) ckalloc((unsigned)(sizeof(double) * (length + 2 + objc)));
    for (i=0; i<beforeThis; i++) {
	new[i] = polyPtr->coordPtr[i];
    }
    for (i=0; i<objc; i++) {
	if (Tcl_GetDoubleFromObj((Tcl_Interp *) NULL,objv[i],
		new+(i+beforeThis))!=TCL_OK) {
	    ckfree((char *) new);
	    return;
	}
    }

    for(i=beforeThis; i<length; i++) {
	new[i+objc] = polyPtr->coordPtr[i];
    }
    if(polyPtr->coordPtr) ckfree((char *) polyPtr->coordPtr);
    length+=objc;
    polyPtr->coordPtr = new;
    polyPtr->numPoints = (length/2) + polyPtr->autoClosed;

    /*
     * Close the polygon if it isn't already closed, or remove autoclosing
     * if the user's coordinates are now closed.
     */

    if (polyPtr->autoClosed) {
	if ((new[length-2] == new[0]) && (new[length-1] == new[1])) {
	    polyPtr->autoClosed = 0;
	    polyPtr->numPoints--;
	}
    }
    else {
	if ((new[length-2] != new[0]) || (new[length-1] != new[1])) {
	    polyPtr->autoClosed = 1;
	    polyPtr->numPoints++;
	}
    }

    new[length] = new[0];
    new[length+1] = new[1];
    if (((length-objc)>3) && (state != TK_STATE_HIDDEN)) {
	/*
	 * This is some optimizing code that will result that only the part
	 * of the polygon that changed (and the objects that are overlapping
	 * with that part) need to be redrawn. A special flag is set that
	 * instructs the general canvas code not to redraw the whole
	 * object. If this flag is not set, the canvas will do the redrawing,
	 * otherwise I have to do it here.
	 */
    	double width;
	int j;
	itemPtr->redraw_flags |= TK_ITEM_DONT_REDRAW;

	/*
	 * The header elements that normally are used for the
	 * bounding box, are now used to calculate the bounding
	 * box for only the part that has to be redrawn. That
	 * doesn't matter, because afterwards the bounding
	 * box has to be re-calculated anyway.
	 */

	itemPtr->x1 = itemPtr->x2 = (int) polyPtr->coordPtr[beforeThis];
	itemPtr->y1 = itemPtr->y2 = (int) polyPtr->coordPtr[beforeThis+1];
	beforeThis-=2; objc+=4;
	if(polyPtr->smooth) {
	    beforeThis-=2; objc+=4;
	} /* be carefull; beforeThis could now be negative */
	for(i=beforeThis; i<beforeThis+objc; i+=2) {
		j=i;
		if(j<0) j+=length;
		if(j>=length) j-=length;
		TkIncludePoint(itemPtr, polyPtr->coordPtr+j);
	}
	width = polyPtr->outline.width;
	if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
		if (polyPtr->outline.activeWidth>width) {
		    width = polyPtr->outline.activeWidth;
		}
	} else if (state==TK_STATE_DISABLED) {
		if (polyPtr->outline.disabledWidth>0.0) {
		    width = polyPtr->outline.disabledWidth;
		}
	}
	itemPtr->x1 -= (int) width; itemPtr->y1 -= (int) width;
	itemPtr->x2 += (int) width; itemPtr->y2 += (int) width;
	Tk_CanvasEventuallyRedraw(canvas,
		itemPtr->x1, itemPtr->y1,
		itemPtr->x2, itemPtr->y2);
    }

    ComputePolygonBbox(canvas, polyPtr);
}

/*
 *--------------------------------------------------------------
 *
 * PolygonDeleteCoords --
 *
 *	Delete one or more coordinates from a polygon item.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Characters between "first" and "last", inclusive, get
 *	deleted from itemPtr.
 *
 *--------------------------------------------------------------
 */

static void
PolygonDeleteCoords(canvas, itemPtr, first, last)
    Tk_Canvas canvas;		/* Canvas containing itemPtr. */
    Tk_Item *itemPtr;		/* Item in which to delete characters. */
    int first;			/* Index of first character to delete. */
    int last;			/* Index of last character to delete. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    int count, i;
    int length = 2*(polyPtr->numPoints - polyPtr->autoClosed);

    while(first>=length) first-=length;
    while(first<0)	 first+=length;
    while(last>=length)	 last-=length;
    while(last<0)	 last+=length;

    first &= -2;
    last &= -2;

    count = last + 2 - first;
    if(count<=0) count +=length;

    if(count >= length) {
	polyPtr->numPoints = 0;
	if(polyPtr->coordPtr != NULL) {
	    ckfree((char *) polyPtr->coordPtr);
	}
	ComputePolygonBbox(canvas, polyPtr);
	return;
    }

    if(last>=first) {
	for(i=last+2; i<length; i++) {
	    polyPtr->coordPtr[i-count] = polyPtr->coordPtr[i];
	}
    } else {
	for(i=last; i<=first; i++) {
	    polyPtr->coordPtr[i-last] = polyPtr->coordPtr[i];
	}
    }
    polyPtr->coordPtr[length-count] = polyPtr->coordPtr[0];
    polyPtr->coordPtr[length-count+1] = polyPtr->coordPtr[1];
    polyPtr->numPoints -= count/2;
    ComputePolygonBbox(canvas, polyPtr);
}

/*
 *--------------------------------------------------------------
 *
 * PolygonToPoint --
 *
 *	Computes the distance from a given point to a given
 *	polygon, in canvas units.
 *
 * Results:
 *	The return value is 0 if the point whose x and y coordinates
 *	are pointPtr[0] and pointPtr[1] is inside the polygon.  If the
 *	point isn't inside the polygon then the return value is the
 *	distance from the point to the polygon.
 *
 * Side effects:
 *	None.
 *
 *--------------------------------------------------------------
 */

	/* ARGSUSED */
static double
PolygonToPoint(canvas, itemPtr, pointPtr)
    Tk_Canvas canvas;		/* Canvas containing item. */
    Tk_Item *itemPtr;		/* Item to check against point. */
    double *pointPtr;		/* Pointer to x and y coordinates. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    double *coordPtr, *polyPoints;
    double staticSpace[2*MAX_STATIC_POINTS];
    double poly[10];
    double radius;
    double bestDist, dist;
    int numPoints, count;
    int changedMiterToBevel;	/* Non-zero means that a mitered corner
				 * had to be treated as beveled after all
				 * because the angle was < 11 degrees. */
    double width;
    Tk_State state = itemPtr->state;

    bestDist = 1.0e36;

    if(state == TK_STATE_NULL) {
	state = ((TkCanvas *)canvas)->canvas_state;
    }
    width = polyPtr->outline.width;
    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
	if (polyPtr->outline.activeWidth>width) {
	    width = polyPtr->outline.activeWidth;
	}
    } else if (state==TK_STATE_DISABLED) {
	if (polyPtr->outline.disabledWidth>0.0) {
	    width = polyPtr->outline.disabledWidth;
	}
    }
    radius = width/2.0;

    /*
     * Handle smoothed polygons by generating an expanded set of points
     * against which to do the check.
     */

    if ((polyPtr->smooth) && (polyPtr->numPoints>2)) {
	numPoints = polyPtr->smooth->coordProc(canvas, (double *) NULL,
		polyPtr->numPoints, polyPtr->splineSteps, (XPoint *) NULL,
		(double *) NULL);
	if (numPoints <= MAX_STATIC_POINTS) {
	    polyPoints = staticSpace;
	} else {
	    polyPoints = (double *) ckalloc((unsigned)
		    (2*numPoints*sizeof(double)));
	}
	numPoints = polyPtr->smooth->coordProc(canvas, polyPtr->coordPtr,
		polyPtr->numPoints, polyPtr->splineSteps, (XPoint *) NULL,
		polyPoints);
    } else {
	numPoints = polyPtr->numPoints;
	polyPoints = polyPtr->coordPtr;
    }

    bestDist = TkPolygonToPoint(polyPoints, numPoints, pointPtr);
    if (bestDist<=0.0) {
	goto donepoint;
    }
    if ((polyPtr->outline.gc != None) && (polyPtr->joinStyle == JoinRound)) {
	dist = bestDist - radius;
	if (dist <= 0.0) {
	    bestDist = 0.0;
	    goto donepoint;
	} else {
	    bestDist = dist;
	}
    }

    if ((polyPtr->outline.gc == None) || (width <= 1)) goto donepoint;

    /*
     * The overall idea is to iterate through all of the edges of
     * the line, computing a polygon for each edge and testing the
     * point against that polygon.  In addition, there are additional
     * tests to deal with rounded joints and caps.
     */

    changedMiterToBevel = 0;
    for (count = numPoints, coordPtr = polyPoints; count >= 2;
	    count--, coordPtr += 2) {

	/*
	 * If rounding is done around the first point then compute
	 * the distance between the point and the point.
	 */

	if (polyPtr->joinStyle == JoinRound) {
	    dist = hypot(coordPtr[0] - pointPtr[0], coordPtr[1] - pointPtr[1])
		    - radius;
	    if (dist <= 0.0) {
		bestDist = 0.0;
		goto donepoint;
	    } else if (dist < bestDist) {
		bestDist = dist;
	    }
	}

	/*
	 * Compute the polygonal shape corresponding to this edge,
	 * consisting of two points for the first point of the edge
	 * and two points for the last point of the edge.
	 */

	if (count == numPoints) {
	    TkGetButtPoints(coordPtr+2, coordPtr, (double) width,
		    0, poly, poly+2);
	} else if ((polyPtr->joinStyle == JoinMiter) && !changedMiterToBevel) {
	    poly[0] = poly[6];
	    poly[1] = poly[7];
	    poly[2] = poly[4];
	    poly[3] = poly[5];
	} else {
	    TkGetButtPoints(coordPtr+2, coordPtr, (double) width, 0,
		    poly, poly+2);

	    /*
	     * If this line uses beveled joints, then check the distance
	     * to a polygon comprising the last two points of the previous
	     * polygon and the first two from this polygon;  this checks
	     * the wedges that fill the mitered joint.
	     */

	    if ((polyPtr->joinStyle == JoinBevel) || changedMiterToBevel) {
		poly[8] = poly[0];
		poly[9] = poly[1];
		dist = TkPolygonToPoint(poly, 5, pointPtr);
		if (dist <= 0.0) {
		    bestDist = 0.0;
		    goto donepoint;
		} else if (dist < bestDist) {
		    bestDist = dist;
		}
		changedMiterToBevel = 0;
	    }
	}
	if (count == 2) {
	    TkGetButtPoints(coordPtr, coordPtr+2, (double) width,
		    0, poly+4, poly+6);
	} else if (polyPtr->joinStyle == JoinMiter) {
	    if (TkGetMiterPoints(coordPtr, coordPtr+2, coordPtr+4,
		    (double) width, poly+4, poly+6) == 0) {
		changedMiterToBevel = 1;
		TkGetButtPoints(coordPtr, coordPtr+2, (double) width,
			0, poly+4, poly+6);
	    }
	} else {
	    TkGetButtPoints(coordPtr, coordPtr+2, (double) width, 0,
		    poly+4, poly+6);
	}
	poly[8] = poly[0];
	poly[9] = poly[1];
	dist = TkPolygonToPoint(poly, 5, pointPtr);
	if (dist <= 0.0) {
	    bestDist = 0.0;
	    goto donepoint;
	} else if (dist < bestDist) {
	    bestDist = dist;
	}
    }

    donepoint:
    if ((polyPoints != staticSpace) && polyPoints != polyPtr->coordPtr) {
	ckfree((char *) polyPoints);
    }
    return bestDist;
}

/*
 *--------------------------------------------------------------
 *
 * PolygonToArea --
 *
 *	This procedure is called to determine whether an item
 *	lies entirely inside, entirely outside, or overlapping
 *	a given rectangular area.
 *
 * Results:
 *	-1 is returned if the item is entirely outside the area
 *	given by rectPtr, 0 if it overlaps, and 1 if it is entirely
 *	inside the given area.
 *
 * Side effects:
 *	None.
 *
 *--------------------------------------------------------------
 */

	/* ARGSUSED */
static int
PolygonToArea(canvas, itemPtr, rectPtr)
    Tk_Canvas canvas;		/* Canvas containing item. */
    Tk_Item *itemPtr;		/* Item to check against polygon. */
    double *rectPtr;		/* Pointer to array of four coordinates
				 * (x1, y1, x2, y2) describing rectangular
				 * area.  */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    double *coordPtr;
    double staticSpace[2*MAX_STATIC_POINTS];
    double *polyPoints, poly[10];
    double radius;
    int numPoints, count;
    int changedMiterToBevel;	/* Non-zero means that a mitered corner
				 * had to be treated as beveled after all
				 * because the angle was < 11 degrees. */
    int inside;			/* Tentative guess about what to return,
				 * based on all points seen so far:  one
				 * means everything seen so far was
				 * inside the area;  -1 means everything
				 * was outside the area.  0 means overlap
				 * has been found. */ 
    double width;
    Tk_State state = itemPtr->state;

    if(state == TK_STATE_NULL) {
	state = ((TkCanvas *)canvas)->canvas_state;
    }

    width = polyPtr->outline.width;
    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
	if (polyPtr->outline.activeWidth>width) {
	    width = polyPtr->outline.activeWidth;
	}
    } else if (state==TK_STATE_DISABLED) {
	if (polyPtr->outline.disabledWidth>0.0) {
	    width = polyPtr->outline.disabledWidth;
	}
    }

    radius = width/2.0;
    inside = -1;

    if ((state==TK_STATE_HIDDEN) || polyPtr->numPoints<2) {
	return -1;
    } else if (polyPtr->numPoints <3) {
	double oval[4];
	oval[0] = polyPtr->coordPtr[0]-radius;
	oval[1] = polyPtr->coordPtr[1]-radius;
	oval[2] = polyPtr->coordPtr[0]+radius;
	oval[3] = polyPtr->coordPtr[1]+radius;
	return TkOvalToArea(oval, rectPtr);
    }
    /*
     * Handle smoothed polygons by generating an expanded set of points
     * against which to do the check.
     */

    if (polyPtr->smooth) {
	numPoints = polyPtr->smooth->coordProc(canvas, (double *) NULL,
		polyPtr->numPoints, polyPtr->splineSteps, (XPoint *) NULL,
		(double *) NULL);
	if (numPoints <= MAX_STATIC_POINTS) {
	    polyPoints = staticSpace;
	} else {
	    polyPoints = (double *) ckalloc((unsigned)
		    (2*numPoints*sizeof(double)));
	}
	numPoints = polyPtr->smooth->coordProc(canvas, polyPtr->coordPtr,
		polyPtr->numPoints, polyPtr->splineSteps, (XPoint *) NULL,
		polyPoints);
    } else {
	numPoints = polyPtr->numPoints;
	polyPoints = polyPtr->coordPtr;
    }

    /*
     * Simple test to see if we are in the polygon.  Polygons are
     * different from othe canvas items in that they register points
     * being inside even if it isn't filled.
     */
    inside = TkPolygonToArea(polyPoints, numPoints, rectPtr);
    if (inside==0) goto donearea;

    if (polyPtr->outline.gc == None) goto donearea ;

    /*
     * Iterate through all of the edges of the line, computing a polygon
     * for each edge and testing the area against that polygon.  In
     * addition, there are additional tests to deal with rounded joints
     * and caps.
     */

    changedMiterToBevel = 0;
    for (count = numPoints, coordPtr = polyPoints; count >= 2;
	    count--, coordPtr += 2) {
 
	/*
	 * If rounding is done around the first point of the edge
	 * then test a circular region around the point with the
	 * area.
	 */

	if (polyPtr->joinStyle == JoinRound) {
	    poly[0] = coordPtr[0] - radius;
	    poly[1] = coordPtr[1] - radius;
	    poly[2] = coordPtr[0] + radius;
	    poly[3] = coordPtr[1] + radius;
	    if (TkOvalToArea(poly, rectPtr) != inside) {
		inside = 0;
		goto donearea;
	    }
	}

	/*
	 * Compute the polygonal shape corresponding to this edge,
	 * consisting of two points for the first point of the edge
	 * and two points for the last point of the edge.
	 */

	if (count == numPoints) {
	    TkGetButtPoints(coordPtr+2, coordPtr, width,
		    0, poly, poly+2);
	} else if ((polyPtr->joinStyle == JoinMiter) && !changedMiterToBevel) {
	    poly[0] = poly[6];
	    poly[1] = poly[7];
	    poly[2] = poly[4];
	    poly[3] = poly[5];
	} else {
	    TkGetButtPoints(coordPtr+2, coordPtr, width, 0,
		    poly, poly+2);

	    /*
	     * If the last joint was beveled, then also check a
	     * polygon comprising the last two points of the previous
	     * polygon and the first two from this polygon;  this checks
	     * the wedges that fill the beveled joint.
	     */

	    if ((polyPtr->joinStyle == JoinBevel) || changedMiterToBevel) {
		poly[8] = poly[0];
		poly[9] = poly[1];
		if (TkPolygonToArea(poly, 5, rectPtr) != inside) {
		    inside = 0;
		    goto donearea;
		}
		changedMiterToBevel = 0;
	    }
	}
	if (count == 2) {
	    TkGetButtPoints(coordPtr, coordPtr+2, width,
		    0, poly+4, poly+6);
	} else if (polyPtr->joinStyle == JoinMiter) {
	    if (TkGetMiterPoints(coordPtr, coordPtr+2, coordPtr+4,
		    width, poly+4, poly+6) == 0) {
		changedMiterToBevel = 1;
		TkGetButtPoints(coordPtr, coordPtr+2, width,
			0, poly+4, poly+6);
	    }
	} else {
	    TkGetButtPoints(coordPtr, coordPtr+2, width, 0,
		    poly+4, poly+6);
	}
	poly[8] = poly[0];
	poly[9] = poly[1];
	if (TkPolygonToArea(poly, 5, rectPtr) != inside) {
	    inside = 0;
	    goto donearea;
	}
    }

    donearea:
    if ((polyPoints != staticSpace) && (polyPoints != polyPtr->coordPtr)) {
	ckfree((char *) polyPoints);
    }
    return inside;
}

/*
 *--------------------------------------------------------------
 *
 * ScalePolygon --
 *
 *	This procedure is invoked to rescale a polygon item.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The polygon referred to by itemPtr is rescaled so that the
 *	following transformation is applied to all point
 *	coordinates:
 *		x' = originX + scaleX*(x-originX)
 *		y' = originY + scaleY*(y-originY)
 *
 *--------------------------------------------------------------
 */

static void
ScalePolygon(canvas, itemPtr, originX, originY, scaleX, scaleY)
    Tk_Canvas canvas;			/* Canvas containing polygon. */
    Tk_Item *itemPtr;			/* Polygon to be scaled. */
    double originX, originY;		/* Origin about which to scale rect. */
    double scaleX;			/* Amount to scale in X direction. */
    double scaleY;			/* Amount to scale in Y direction. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    double *coordPtr;
    int i;

    for (i = 0, coordPtr = polyPtr->coordPtr; i < polyPtr->numPoints;
	    i++, coordPtr += 2) {
	*coordPtr = originX + scaleX*(*coordPtr - originX);
	coordPtr[1] = originY + scaleY*(coordPtr[1] - originY);
    }
    ComputePolygonBbox(canvas, polyPtr);
}

/*
 *--------------------------------------------------------------
 *
 * GetPolygonIndex --
 *
 *	Parse an index into a polygon item and return either its value
 *	or an error.
 *
 * Results:
 *	A standard Tcl result.  If all went well, then *indexPtr is
 *	filled in with the index (into itemPtr) corresponding to
 *	string.  Otherwise an error message is left in
 *	interp->result.
 *
 * Side effects:
 *	None.
 *
 *--------------------------------------------------------------
 */

static int
GetPolygonIndex(interp, canvas, itemPtr, obj, indexPtr)
    Tcl_Interp *interp;		/* Used for error reporting. */
    Tk_Canvas canvas;		/* Canvas containing item. */
    Tk_Item *itemPtr;		/* Item for which the index is being
				 * specified. */
    Tcl_Obj *obj;		/* Specification of a particular coord
				 * in itemPtr's line. */
    int *indexPtr;		/* Where to store converted index. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    size_t length;
    char *string = Tcl_GetStringFromObj(obj, (int *) &length);

    if (string[0] == 'e') {
	if (strncmp(string, "end", length) == 0) {
	    *indexPtr = 2*(polyPtr->numPoints - polyPtr->autoClosed);
	} else {
	    badIndex:

	    /*
	     * Some of the paths here leave messages in interp->result,
	     * so we have to clear it out before storing our own message.
	     */

	    Tcl_SetResult(interp, (char *) NULL, TCL_STATIC);
	    Tcl_AppendResult(interp, "bad index \"", string, "\"",
		    (char *) NULL);
	    return TCL_ERROR;
	}
    } else if (string[0] == '@') {
	int i;
	double x ,y, bestDist, dist, *coordPtr;
	char *end, *p;

	p = string+1;
	x = strtod(p, &end);
	if ((end == p) || (*end != ',')) {
	    goto badIndex;
	}
	p = end+1;
	y = strtod(p, &end);
	if ((end == p) || (*end != 0)) {
	    goto badIndex;
	}
	bestDist = 1.0e36;
	coordPtr = polyPtr->coordPtr;
	*indexPtr = 0;
	for(i=0; i<(polyPtr->numPoints-1); i++) {
	    dist = hypot(coordPtr[0] - x, coordPtr[1] - y);
	    if (dist<bestDist) {
		bestDist = dist;
		*indexPtr = 2*i;
	    }
	    coordPtr += 2;
	}
    } else {
	int count = 2*(polyPtr->numPoints - polyPtr->autoClosed);
	if (Tcl_GetIntFromObj(interp, obj, indexPtr) != TCL_OK) {
	    goto badIndex;
	}
	*indexPtr &= -2; /* if odd, make it even */
	if (count) {
	    if (*indexPtr > 0) {
		*indexPtr = ((*indexPtr - 2) % count) + 2;
	    } else {
		*indexPtr = -((-(*indexPtr)) % count);
	    }
	} else {
	    *indexPtr = 0;
	}
    }
    return TCL_OK;
}

/*
 *--------------------------------------------------------------
 *
 * TranslatePolygon --
 *
 *	This procedure is called to move a polygon by a given
 *	amount.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The position of the polygon is offset by (xDelta, yDelta),
 *	and the bounding box is updated in the generic part of the
 *	item structure.
 *
 *--------------------------------------------------------------
 */

static void
TranslatePolygon(canvas, itemPtr, deltaX, deltaY)
    Tk_Canvas canvas;			/* Canvas containing item. */
    Tk_Item *itemPtr;			/* Item that is being moved. */
    double deltaX, deltaY;		/* Amount by which item is to be
					 * moved. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    double *coordPtr;
    int i;

    for (i = 0, coordPtr = polyPtr->coordPtr; i < polyPtr->numPoints;
	    i++, coordPtr += 2) {
	*coordPtr += deltaX;
	coordPtr[1] += deltaY;
    }
    ComputePolygonBbox(canvas, polyPtr);
}

/*
 *--------------------------------------------------------------
 *
 * PolygonToPostscript --
 *
 *	This procedure is called to generate Postscript for
 *	polygon items.
 *
 * Results:
 *	The return value is a standard Tcl result.  If an error
 *	occurs in generating Postscript then an error message is
 *	left in the interp's result, replacing whatever used
 *	to be there.  If no error occurs, then Postscript for the
 *	item is appended to the result.
 *
 * Side effects:
 *	None.
 *
 *--------------------------------------------------------------
 */

static int
PolygonToPostscript(interp, canvas, itemPtr, prepass)
    Tcl_Interp *interp;			/* Leave Postscript or error message
					 * here. */
    Tk_Canvas canvas;			/* Information about overall canvas. */
    Tk_Item *itemPtr;			/* Item for which Postscript is
					 * wanted. */
    int prepass;			/* 1 means this is a prepass to
					 * collect font information;  0 means
					 * final Postscript is being created. */
{
    PolygonItem *polyPtr = (PolygonItem *) itemPtr;
    char *style;
    XColor *color;
    XColor *fillColor;
    Pixmap stipple;
    Pixmap fillStipple;
    Tk_State state = itemPtr->state;
    double width;

    if (polyPtr->numPoints<2 || polyPtr->coordPtr==NULL) {
	return TCL_OK;
    }

    if(state == TK_STATE_NULL) {
	state = ((TkCanvas *)canvas)->canvas_state;
    }
    width = polyPtr->outline.width;
    color = polyPtr->outline.color;
    stipple = polyPtr->fillStipple;
    fillColor = polyPtr->fillColor;
    fillStipple = polyPtr->fillStipple;
    if (((TkCanvas *)canvas)->currentItemPtr == itemPtr) {
	if (polyPtr->outline.activeWidth>width) {
	    width = polyPtr->outline.activeWidth;
	}
	if (polyPtr->outline.activeColor!=NULL) {
	    color = polyPtr->outline.activeColor;
	}
	if (polyPtr->outline.activeStipple!=None) {
	    stipple = polyPtr->outline.activeStipple;
	}
	if (polyPtr->activeFillColor!=NULL) {
	    fillColor = polyPtr->activeFillColor;
	}
	if (polyPtr->activeFillStipple!=None) {
	    fillStipple = polyPtr->activeFillStipple;
	}
    } else if (state==TK_STATE_DISABLED) {
	if (polyPtr->outline.disabledWidth>0.0) {
	    width = polyPtr->outline.disabledWidth;
	}
	if (polyPtr->outline.disabledColor!=NULL) {
	    color = polyPtr->outline.disabledColor;
	}
	if (polyPtr->outline.disabledStipple!=None) {
	    stipple = polyPtr->outline.disabledStipple;
	}
	if (polyPtr->disabledFillColor!=NULL) {
	    fillColor = polyPtr->disabledFillColor;
	}
	if (polyPtr->disabledFillStipple!=None) {
	    fillStipple = polyPtr->disabledFillStipple;
	}
    }
    if (polyPtr->numPoints==2) {
	char string[128];
	if (color == NULL) {
	    return TCL_OK;
	}

	sprintf(string, "%.15g %.15g translate %.15g %.15g",
		polyPtr->coordPtr[0], Tk_CanvasPsY(canvas, polyPtr->coordPtr[1]),
		width/2.0, width/2.0);
	Tcl_AppendResult(interp, "matrix currentmatrix\n",string,
		" scale 1 0 moveto 0 0 1 0 360 arc\nsetmatrix\n", (char *) NULL);
	if (Tk_CanvasPsColor(interp, canvas, color) != TCL_OK) {
	    return TCL_ERROR;
	}
	if (stipple != None) {
	    Tcl_AppendResult(interp, "clip ", (char *) NULL);
	    if (Tk_CanvasPsStipple(interp, canvas, stipple) != TCL_OK) {
		return TCL_ERROR;
	    }
	} else {
	    Tcl_AppendResult(interp, "fill\n", (char *) NULL);
	}
	return TCL_OK;
    }

    /*
     * Fill the area of the polygon.
     */

    if (fillColor != NULL && polyPtr->numPoints>3) {
	if (!polyPtr->smooth || !polyPtr->smooth->postscriptProc) {
	    Tk_CanvasPsPath(interp, canvas, polyPtr->coordPtr,
		    polyPtr->numPoints);
	} else {
	    polyPtr->smooth->postscriptProc(interp, canvas, polyPtr->coordPtr,
		    polyPtr->numPoints, polyPtr->splineSteps);
	}
	if (Tk_CanvasPsColor(interp, canvas, fillColor) != TCL_OK) {
	    return TCL_ERROR;
	}
	if (fillStipple != None) {
	    Tcl_AppendResult(interp, "eoclip ", (char *) NULL);
	    if (Tk_CanvasPsStipple(interp, canvas, fillStipple)
		    != TCL_OK) {
		return TCL_ERROR;
	    }
	    if (color != NULL) {
		Tcl_AppendResult(interp, "grestore gsave\n", (char *) NULL);
	    }
	} else {
	    Tcl_AppendResult(interp, "eofill\n", (char *) NULL);
	}
    }

    /*
     * Now draw the outline, if there is one.
     */

    if (color != NULL) {

	if (!polyPtr->smooth || !polyPtr->smooth->postscriptProc) {
	    Tk_CanvasPsPath(interp, canvas, polyPtr->coordPtr,
		polyPtr->numPoints);
	} else {
	    polyPtr->smooth->postscriptProc(interp, canvas, polyPtr->coordPtr,
		polyPtr->numPoints, polyPtr->splineSteps);
	}

	if (polyPtr->joinStyle == JoinRound) {
	    style = "1";
	} else if (polyPtr->joinStyle == JoinBevel) {
	    style = "2";
	} else {
	    style = "0";
	}
	Tcl_AppendResult(interp, style," setlinejoin 1 setlinecap\n",
		(char *) NULL);
	if (Tk_CanvasPsOutline(canvas, itemPtr,
		&(polyPtr->outline)) != TCL_OK) {
	    return TCL_ERROR;
	}
    }
    return TCL_OK;
}
