Import Micropolis from http://www.donhopkins.com/home/micropolis/

[micropolis] / src / tk / tkrectov.c

/* 
 * tkRectOval.c --
 *
 *      This file implements rectangle and oval items for canvas
 *      widgets.
 *
 * Copyright 1991-1992 Regents of the University of California.
 * Permission to use, copy, modify, and distribute this
 * software and its documentation for any purpose and without
 * fee is hereby granted, provided that the above copyright
 * notice appear in all copies.  The University of California
 * makes no representations about the suitability of this
 * software for any purpose.  It is provided "as is" without
 * express or implied warranty.
 */

#ifndef lint
static char rcsid[] = "$Header: /user6/ouster/wish/RCS/tkRectOval.c,v 1.15 92/08/24 09:23:58 ouster Exp $ SPRITE (Berkeley)";
#endif

#include <stdio.h>
#include <math.h>
#include "tkconfig.h"
#include "tkint.h"
#include "tkcanvas.h"

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

typedef struct RectOvalItem  {
    Tk_Item header;             /* Generic stuff that's the same for all
                                 * types.  MUST BE FIRST IN STRUCTURE. */
    double bbox[4];             /* Coordinates of bounding box for rectangle
                                 * or oval (x1, y1, x2, y2).  Item includes
                                 * x1 and x2 but not y1 and y2. */
    int width;                  /* Width of outline. */
    XColor *outlineColor;       /* Color for outline. */
    XColor *fillColor;          /* Color for filling rectangle/oval. */
    Pixmap fillStipple;         /* Stipple bitmap for filling item. */
    GC outlineGC;               /* Graphics context for outline. */
    GC fillGC;                  /* Graphics context for filling item. */
} RectOvalItem;

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

static Tk_ConfigSpec configSpecs[] = {
    {TK_CONFIG_COLOR, "-fill", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(RectOvalItem, fillColor), TK_CONFIG_NULL_OK},
    {TK_CONFIG_COLOR, "-outline", (char *) NULL, (char *) NULL,
        "black", Tk_Offset(RectOvalItem, outlineColor), TK_CONFIG_NULL_OK},
    {TK_CONFIG_BITMAP, "-stipple", (char *) NULL, (char *) NULL,
        (char *) NULL, Tk_Offset(RectOvalItem, fillStipple), TK_CONFIG_NULL_OK},
    {TK_CONFIG_CUSTOM, "-tags", (char *) NULL, (char *) NULL,
        (char *) NULL, 0, TK_CONFIG_NULL_OK, &tkCanvasTagsOption},
    {TK_CONFIG_PIXELS, "-width", (char *) NULL, (char *) NULL,
        "1", Tk_Offset(RectOvalItem, width), TK_CONFIG_DONT_SET_DEFAULT},
    {TK_CONFIG_END, (char *) NULL, (char *) NULL, (char *) NULL,
        (char *) NULL, 0, 0}
};

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

static void             ComputeRectOvalBbox _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            RectOvalItem *rectOvalPtr));
static int              ConfigureRectOval _ANSI_ARGS_((
                            Tk_Canvas *canvasPtr, Tk_Item *itemPtr, int argc,
                            char **argv, int flags));
static int              CreateRectOval _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            struct Tk_Item *itemPtr, int argc, char **argv));
static void             DeleteRectOval _ANSI_ARGS_((Tk_Item *itemPtr));
static void             DisplayRectOval _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, Drawable dst));
static int              OvalToArea _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, double *areaPtr));
static double           OvalToPoint _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, double *pointPtr));
static int              RectOvalCoords _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, int argc, char **argv));
static int              RectToArea _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, double *areaPtr));
static double           RectToPoint _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, double *pointPtr));
static void             ScaleRectOval _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, double originX, double originY,
                            double scaleX, double scaleY));
static void             TranslateRectOval _ANSI_ARGS_((Tk_Canvas *canvasPtr,
                            Tk_Item *itemPtr, double deltaX, double deltaY));

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

Tk_ItemType TkRectangleType = {
    "rectangle",                        /* name */
    sizeof(RectOvalItem),               /* itemSize */
    CreateRectOval,                     /* createProc */
    configSpecs,                        /* configSpecs */
    ConfigureRectOval,                  /* configureProc */
    RectOvalCoords,                     /* coordProc */
    DeleteRectOval,                     /* deleteProc */
    DisplayRectOval,                    /* displayProc */
    0,                                  /* alwaysRedraw */
    RectToPoint,                        /* pointProc */
    RectToArea,                         /* areaProc */
    (Tk_ItemPostscriptProc *) NULL,     /* postscriptProc */
    ScaleRectOval,                      /* scaleProc */
    TranslateRectOval,                  /* translateProc */
    (Tk_ItemIndexProc *) NULL,          /* indexProc */
    (Tk_ItemCursorProc *) NULL,         /* cursorProc */
    (Tk_ItemSelectionProc *) NULL,      /* selectionProc */
    (Tk_ItemInsertProc *) NULL,         /* insertProc */
    (Tk_ItemDCharsProc *) NULL,         /* dTextProc */
    (Tk_ItemType *) NULL                /* nextPtr */
};

Tk_ItemType TkOvalType = {
    "oval",                             /* name */
    sizeof(RectOvalItem),               /* itemSize */
    CreateRectOval,                     /* createProc */
    configSpecs,                        /* configSpecs */
    ConfigureRectOval,                  /* configureProc */
    RectOvalCoords,                     /* coordProc */
    DeleteRectOval,                     /* deleteProc */
    DisplayRectOval,                    /* displayProc */
    0,                                  /* alwaysRedraw */
    OvalToPoint,                        /* pointProc */
    OvalToArea,                         /* areaProc */
    (Tk_ItemPostscriptProc *) NULL,     /* postscriptProc */
    ScaleRectOval,                      /* scaleProc */
    TranslateRectOval,                  /* translateProc */
    (Tk_ItemIndexProc *) NULL,          /* indexProc */
    (Tk_ItemCursorProc *) NULL,         /* cursorProc */
    (Tk_ItemSelectionProc *) NULL,      /* selectionProc */
    (Tk_ItemInsertProc *) NULL,         /* insertProc */
    (Tk_ItemDCharsProc *) NULL,         /* dTextProc */
    (Tk_ItemType *) NULL                /* nextPtr */
};
\f
/*
 *--------------------------------------------------------------
 *
 * CreateRectOval --
 *
 *      This procedure is invoked to create a new rectangle
 *      or oval 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
 *      canvasPtr->interp->result;  in this case itemPtr is
 *      left uninitialized, so it can be safely freed by the
 *      caller.
 *
 * Side effects:
 *      A new rectangle or oval item is created.
 *
 *--------------------------------------------------------------
 */

static int
CreateRectOval(canvasPtr, itemPtr, argc, argv)
    register Tk_Canvas *canvasPtr;      /* Canvas to hold new item. */
    Tk_Item *itemPtr;                   /* Record to hold new item;  header
                                         * has been initialized by caller. */
    int argc;                           /* Number of arguments in argv. */
    char **argv;                        /* Arguments describing rectangle. */
{
    register RectOvalItem *rectOvalPtr = (RectOvalItem *) itemPtr;

    if (argc < 4) {
        Tcl_AppendResult(canvasPtr->interp, "wrong # args:  should be \"",
                Tk_PathName(canvasPtr->tkwin), "\" create ",
                itemPtr->typePtr->name, " x1 y1 x2 y2 ?options?",
                (char *) NULL);
        return TCL_ERROR;
    }

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

    rectOvalPtr->width = 1;
    rectOvalPtr->outlineColor = NULL;
    rectOvalPtr->fillColor = NULL;
    rectOvalPtr->fillStipple = None;
    rectOvalPtr->outlineGC = None;
    rectOvalPtr->fillGC = None;

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

    if ((TkGetCanvasCoord(canvasPtr, argv[0], &rectOvalPtr->bbox[0]) != TCL_OK)
            || (TkGetCanvasCoord(canvasPtr, argv[1],
                &rectOvalPtr->bbox[1]) != TCL_OK)
            || (TkGetCanvasCoord(canvasPtr, argv[2],
                    &rectOvalPtr->bbox[2]) != TCL_OK)
            || (TkGetCanvasCoord(canvasPtr, argv[3],
                    &rectOvalPtr->bbox[3]) != TCL_OK)) {
        return TCL_ERROR;
    }

    if (ConfigureRectOval(canvasPtr, itemPtr, argc-4, argv+4, 0) != TCL_OK) {
        DeleteRectOval(itemPtr);
        return TCL_ERROR;
    }
    return TCL_OK;
}
\f
/*
 *--------------------------------------------------------------
 *
 * RectOvalCoords --
 *
 *      This procedure is invoked to process the "coords" widget
 *      command on rectangles and ovals.  See the user documentation
 *      for details on what it does.
 *
 * Results:
 *      Returns TCL_OK or TCL_ERROR, and sets canvasPtr->interp->result.
 *
 * Side effects:
 *      The coordinates for the given item may be changed.
 *
 *--------------------------------------------------------------
 */

static int
RectOvalCoords(canvasPtr, itemPtr, argc, argv)
    register Tk_Canvas *canvasPtr;      /* Canvas containing item. */
    Tk_Item *itemPtr;                   /* Item whose coordinates are to be
                                         * read or modified. */
    int argc;                           /* Number of coordinates supplied in
                                         * argv. */
    char **argv;                        /* Array of coordinates: x1, y1,
                                         * x2, y2, ... */
{
    register RectOvalItem *rectOvalPtr = (RectOvalItem *) itemPtr;
    char buffer[500];

    if (argc == 0) {
        sprintf(buffer, "%g %g %g %g", rectOvalPtr->bbox[0],
                rectOvalPtr->bbox[1], rectOvalPtr->bbox[2],
                rectOvalPtr->bbox[3]);
        Tcl_SetResult(canvasPtr->interp, buffer, TCL_VOLATILE);
    } else if (argc == 4) {
        if ((TkGetCanvasCoord(canvasPtr, argv[0],
                    &rectOvalPtr->bbox[0]) != TCL_OK)
                || (TkGetCanvasCoord(canvasPtr, argv[1],
                    &rectOvalPtr->bbox[1]) != TCL_OK)
                || (TkGetCanvasCoord(canvasPtr, argv[2],
                        &rectOvalPtr->bbox[2]) != TCL_OK)
                || (TkGetCanvasCoord(canvasPtr, argv[3],
                        &rectOvalPtr->bbox[3]) != TCL_OK)) {
            return TCL_ERROR;
        }
        ComputeRectOvalBbox(canvasPtr, rectOvalPtr);
    } else {
        sprintf(canvasPtr->interp->result,
                "wrong # coordinates:  expected 0 or 4, got %d",
                argc);
        return TCL_ERROR;
    }
    return TCL_OK;
}
\f
/*
 *--------------------------------------------------------------
 *
 * ConfigureRectOval --
 *
 *      This procedure is invoked to configure various aspects
 *      of a rectangle or oval item, such as its border and
 *      background colors.
 *
 * Results:
 *      A standard Tcl result code.  If an error occurs, then
 *      an error message is left in canvasPtr->interp->result.
 *
 * Side effects:
 *      Configuration information, such as colors and stipple
 *      patterns, may be set for itemPtr.
 *
 *--------------------------------------------------------------
 */

static int
ConfigureRectOval(canvasPtr, itemPtr, argc, argv, flags)
    Tk_Canvas *canvasPtr;       /* Canvas containing itemPtr. */
    Tk_Item *itemPtr;           /* Rectangle item to reconfigure. */
    int argc;                   /* Number of elements in argv.  */
    char **argv;                /* Arguments describing things to configure. */
    int flags;                  /* Flags to pass to Tk_ConfigureWidget. */
{
    register RectOvalItem *rectOvalPtr = (RectOvalItem *) itemPtr;
    XGCValues gcValues;
    GC newGC;
    unsigned long mask;

    if (Tk_ConfigureWidget(canvasPtr->interp, canvasPtr->tkwin,
            configSpecs, argc, argv, (char *) rectOvalPtr, flags) != TCL_OK) {
        return TCL_ERROR;
    }

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

    if (rectOvalPtr->outlineColor == NULL) {
        newGC = None;
    } else {
        gcValues.foreground = rectOvalPtr->outlineColor->pixel;
        gcValues.cap_style = CapProjecting;
        if (rectOvalPtr->width < 0) {
            rectOvalPtr->width = 1;
        }
        gcValues.line_width = rectOvalPtr->width;
        mask = GCForeground|GCCapStyle|GCLineWidth;
        newGC = Tk_GetGC(canvasPtr->tkwin, mask, &gcValues);
    }
    if (rectOvalPtr->outlineGC != None) {
        Tk_FreeGC(rectOvalPtr->outlineGC);
    }
    rectOvalPtr->outlineGC = newGC;

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

    return TCL_OK;
}
\f
/*
 *--------------------------------------------------------------
 *
 * DeleteRectOval --
 *
 *      This procedure is called to clean up the data structure
 *      associated with a rectangle or oval item.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Resources associated with itemPtr are released.
 *
 *--------------------------------------------------------------
 */

static void
DeleteRectOval(itemPtr)
    Tk_Item *itemPtr;                   /* Item that is being deleted. */
{
    register RectOvalItem *rectOvalPtr = (RectOvalItem *) itemPtr;

    if (rectOvalPtr->outlineColor != NULL) {
        Tk_FreeColor(rectOvalPtr->outlineColor);
    }
    if (rectOvalPtr->fillColor != NULL) {
        Tk_FreeColor(rectOvalPtr->fillColor);
    }
    if (rectOvalPtr->fillStipple != None) {
        Tk_FreeBitmap(rectOvalPtr->fillStipple);
    }
    if (rectOvalPtr->outlineGC != None) {
        Tk_FreeGC(rectOvalPtr->outlineGC);
    }
    if (rectOvalPtr->fillGC != None) {
        Tk_FreeGC(rectOvalPtr->fillGC);
    }
}
\f
/*
 *--------------------------------------------------------------
 *
 * ComputeRectOvalBbox --
 *
 *      This procedure is invoked to compute the bounding box of
 *      all the pixels that may be drawn as part of a rectangle
 *      or oval.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The fields x1, y1, x2, and y2 are updated in the header
 *      for itemPtr.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static void
ComputeRectOvalBbox(canvasPtr, rectOvalPtr)
    Tk_Canvas *canvasPtr;               /* Canvas that contains item. */
    register RectOvalItem *rectOvalPtr; /* Item whose bbox is to be
                                         * recomputed. */
{
    int bloat;

    /*
     * Make sure that the first coordinates are the lowest ones.
     */

    if (rectOvalPtr->bbox[1] > rectOvalPtr->bbox[3]) {
        double tmp;
        tmp = rectOvalPtr->bbox[3];
        rectOvalPtr->bbox[3] = rectOvalPtr->bbox[1];
        rectOvalPtr->bbox[1] = tmp;
    }
    if (rectOvalPtr->bbox[0] > rectOvalPtr->bbox[2]) {
        double tmp;
        tmp = rectOvalPtr->bbox[2];
        rectOvalPtr->bbox[2] = rectOvalPtr->bbox[0];
        rectOvalPtr->bbox[0] = tmp;
    }

    bloat = (rectOvalPtr->width+1)/2 + 1;
    rectOvalPtr->header.x1 = rectOvalPtr->bbox[0] - bloat;
    rectOvalPtr->header.y1 = rectOvalPtr->bbox[1] - bloat;
    rectOvalPtr->header.x2 = rectOvalPtr->bbox[2] + bloat;
    rectOvalPtr->header.y2 = rectOvalPtr->bbox[3] + bloat;
}
\f
/*
 *--------------------------------------------------------------
 *
 * DisplayRectOval --
 *
 *      This procedure is invoked to draw a rectangle or oval
 *      item in a given drawable.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      ItemPtr is drawn in drawable using the transformation
 *      information in canvasPtr.
 *
 *--------------------------------------------------------------
 */

static void
DisplayRectOval(canvasPtr, itemPtr, drawable)
    register Tk_Canvas *canvasPtr;      /* Canvas that contains item. */
    Tk_Item *itemPtr;                   /* Item to be displayed. */
    Drawable drawable;                  /* Pixmap or window in which to draw
                                         * item. */
{
    register RectOvalItem *rectOvalPtr = (RectOvalItem *) itemPtr;
    Display *display = Tk_Display(canvasPtr->tkwin);
    int x1, y1, x2, y2;

    /*
     * Compute the screen coordinates of the bounding box for the item.
     * Make sure that the bbox is at least one pixel large, since some
     * X servers will die if it isn't.
     */

    x1 = SCREEN_X(canvasPtr, rectOvalPtr->bbox[0]);
    y1 = SCREEN_Y(canvasPtr, rectOvalPtr->bbox[1]);
    x2 = SCREEN_X(canvasPtr, rectOvalPtr->bbox[2]);
    y2 = SCREEN_Y(canvasPtr, rectOvalPtr->bbox[3]);
    if (x2 <= x1) {
        x2 = x1+1;
    }
    if (y2 <= y1) {
        y2 = y1+1;
    }

    /*
     * Display filled box first (if wanted), then outline.
     */

    if (rectOvalPtr->fillGC != None) {
        if (rectOvalPtr->header.typePtr == &TkRectangleType) {
            XFillRectangle(display, drawable, rectOvalPtr->fillGC,
                    x1, y1, (unsigned int) (x2-x1), (unsigned int) (y2-y1));
        } else {
            XFillArc(display, drawable, rectOvalPtr->fillGC,
                    x1, y1, (x2-x1), (y2-y1), 0, 360*64);
        }
    }
    if (rectOvalPtr->outlineGC != None) {
        if (rectOvalPtr->header.typePtr == &TkRectangleType) {
            XDrawRectangle(display, drawable, rectOvalPtr->outlineGC,
                    x1, y1, (x2-x1-1), (y2-y1-1));
        } else {
            XDrawArc(display, drawable, rectOvalPtr->outlineGC,
                    x1, y1, (x2-x1-1), (y2-y1-1), 0, 360*64);
        }
    }
}
\f
/*
 *--------------------------------------------------------------
 *
 * RectToPoint --
 *
 *      Computes the distance from a given point to a given
 *      rectangle, in canvas units.
 *
 * Results:
 *      The return value is 0 if the point whose x and y coordinates
 *      are coordPtr[0] and coordPtr[1] is inside the rectangle.  If the
 *      point isn't inside the rectangle then the return value is the
 *      distance from the point to the rectangle.  If itemPtr is filled,
 *      then anywhere in the interior is considered "inside"; if
 *      itemPtr isn't filled, then "inside" means only the area
 *      occupied by the outline.
 *
 * Side effects:
 *      None.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static double
RectToPoint(canvasPtr, itemPtr, pointPtr)
    Tk_Canvas *canvasPtr;       /* Canvas containing item. */
    Tk_Item *itemPtr;           /* Item to check against point. */
    double *pointPtr;           /* Pointer to x and y coordinates. */
{
    register RectOvalItem *rectPtr = (RectOvalItem *) itemPtr;
    double xDiff, yDiff, x1, y1, x2, y2, inc, tmp;

    /*
     * Generate a new larger rectangle that includes the border
     * width, if there is one.
     */

    x1 = rectPtr->bbox[0];
    y1 = rectPtr->bbox[1];
    x2 = rectPtr->bbox[2];
    y2 = rectPtr->bbox[3];
    if (rectPtr->outlineGC != None) {
        inc = rectPtr->width/2.0;
        x1 -= inc;
        y1 -= inc;
        x2 += inc;
        y2 += inc;
    }

    /*
     * If the point is inside the rectangle, handle specially:
     * distance is 0 if rectangle is filled, otherwise compute
     * distance to nearest edge of rectangle and subtract width
     * of edge.
     */

    if ((pointPtr[0] >= x1) && (pointPtr[0] < x2)
                && (pointPtr[1] >= y1) && (pointPtr[1] < y2)) {
        if ((rectPtr->fillGC != None) || (rectPtr->outlineGC == None)) {
            return 0.0;
        }
        xDiff = pointPtr[0] - x1;
        tmp = x2 - pointPtr[0];
        if (tmp < xDiff) {
            xDiff = tmp;
        }
        yDiff = pointPtr[1] - y1;
        tmp = y2 - pointPtr[1];
        if (tmp < yDiff) {
            yDiff = tmp;
        }
        if (yDiff < xDiff) {
            xDiff = yDiff;
        }
        xDiff -= rectPtr->width;
        if (xDiff < 0.0) {
            return 0.0;
        }
        return xDiff;
    }

    /*
     * Point is outside rectangle.
     */

    if (pointPtr[0] < x1) {
        xDiff = x1 - pointPtr[0];
    } else if (pointPtr[0] > x2)  {
        xDiff = pointPtr[0] - x2;
    } else {
        xDiff = 0;
    }

    if (pointPtr[1] < y1) {
        yDiff = y1 - pointPtr[1];
    } else if (pointPtr[1] > y2)  {
        yDiff = pointPtr[1] - y2;
    } else {
        yDiff = 0;
    }

    return hypot(xDiff, yDiff);
}
\f
/*
 *--------------------------------------------------------------
 *
 * OvalToPoint --
 *
 *      Computes the distance from a given point to a given
 *      oval, in canvas units.
 *
 * Results:
 *      The return value is 0 if the point whose x and y coordinates
 *      are coordPtr[0] and coordPtr[1] is inside the oval.  If the
 *      point isn't inside the oval then the return value is the
 *      distance from the point to the oval.  If itemPtr is filled,
 *      then anywhere in the interior is considered "inside"; if
 *      itemPtr isn't filled, then "inside" means only the area
 *      occupied by the outline.
 *
 * Side effects:
 *      None.
 *
 *--------------------------------------------------------------
 */

        /* ARGSUSED */
static double
OvalToPoint(canvasPtr, itemPtr, pointPtr)
    Tk_Canvas *canvasPtr;       /* Canvas containing item. */
    Tk_Item *itemPtr;           /* Item to check against point. */
    double *pointPtr;           /* Pointer to x and y coordinates. */
{
    register RectOvalItem *ovalPtr = (RectOvalItem *) itemPtr;
    double width;
    int filled;

    width = ovalPtr->width;
    filled = ovalPtr->fillGC != None;
    if (ovalPtr->outlineGC == None) {
        width = 0.0;
        filled = 1;
    }
    return TkOvalToPoint(ovalPtr->bbox, width, filled, pointPtr);
}
\f
/*
 *--------------------------------------------------------------
 *
 * RectToArea --
 *
 *      This procedure is called to determine whether an item
 *      lies entirely inside, entirely outside, or overlapping
 *      a given rectangle.
 *
 * 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
RectToArea(canvasPtr, itemPtr, areaPtr)
    Tk_Canvas *canvasPtr;       /* Canvas containing item. */
    Tk_Item *itemPtr;           /* Item to check against rectangle. */
    double *areaPtr;            /* Pointer to array of four coordinates
                                 * (x1, y1, x2, y2) describing rectangular
                                 * area.  */
{
    register RectOvalItem *rectPtr = (RectOvalItem *) itemPtr;
    double halfWidth;

    halfWidth = rectPtr->width/2.0;
    if (rectPtr->outlineGC == None) {
        halfWidth = 0.0;
    }

    if ((areaPtr[2] <= (rectPtr->bbox[0] - halfWidth))
            || (areaPtr[0] >= (rectPtr->bbox[2] + halfWidth))
            || (areaPtr[3] <= (rectPtr->bbox[1] - halfWidth))
            || (areaPtr[1] >= (rectPtr->bbox[3] + halfWidth))) {
        return -1;
    }
    if ((rectPtr->fillGC == None) && (rectPtr->outlineGC != None)
            && (areaPtr[0] >= (rectPtr->bbox[0] + halfWidth))
            && (areaPtr[1] >= (rectPtr->bbox[1] + halfWidth))
            && (areaPtr[2] <= (rectPtr->bbox[2] - halfWidth))
            && (areaPtr[3] <= (rectPtr->bbox[3] - halfWidth))) {
        return -1;
    }
    if ((areaPtr[0] <= (rectPtr->bbox[0] - halfWidth))
            && (areaPtr[1] <= (rectPtr->bbox[1] - halfWidth))
            && (areaPtr[2] >= (rectPtr->bbox[2] + halfWidth))
            && (areaPtr[3] >= (rectPtr->bbox[3] + halfWidth))) {
        return 1;
    }
    return 0;
}
\f
/*
 *--------------------------------------------------------------
 *
 * OvalToArea --
 *
 *      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
OvalToArea(canvasPtr, itemPtr, areaPtr)
    Tk_Canvas *canvasPtr;       /* Canvas containing item. */
    Tk_Item *itemPtr;           /* Item to check against oval. */
    double *areaPtr;            /* Pointer to array of four coordinates
                                 * (x1, y1, x2, y2) describing rectangular
                                 * area.  */
{
    register RectOvalItem *ovalPtr = (RectOvalItem *) itemPtr;
    double oval[4], halfWidth;
    int result;

    /*
     * Expand the oval to include the width of the outline, if any.
     */

    halfWidth = ovalPtr->width/2.0;
    if (ovalPtr->outlineGC == None) {
        halfWidth = 0.0;
    }
    oval[0] = ovalPtr->bbox[0] - halfWidth;
    oval[1] = ovalPtr->bbox[1] - halfWidth;
    oval[2] = ovalPtr->bbox[2] + halfWidth;
    oval[3] = ovalPtr->bbox[3] + halfWidth;

    result = TkOvalToArea(oval, areaPtr);

    /*
     * If the rectangle appears to overlap the oval and the oval
     * isn't filled, do one more check to see if perhaps all four
     * of the rectangle's corners are totally inside the oval's
     * unfilled center, in which case we should return "outside".
     */

    if ((result == 0) && (ovalPtr->outlineGC != NULL)
            && (ovalPtr->fillGC == NULL)) {
        double centerX, centerY, width, height;
        double xDelta1, yDelta1, xDelta2, yDelta2;

        centerX = (ovalPtr->bbox[0] + ovalPtr->bbox[2])/2.0;
        centerY = (ovalPtr->bbox[1] + ovalPtr->bbox[3])/2.0;
        width = (ovalPtr->bbox[2] - ovalPtr->bbox[0])/2.0 - halfWidth;
        height = (ovalPtr->bbox[3] - ovalPtr->bbox[1])/2.0 - halfWidth;
        xDelta1 = (areaPtr[0] - centerX)/width;
        xDelta1 *= xDelta1;
        yDelta1 = (areaPtr[1] - centerY)/height;
        yDelta1 *= yDelta1;
        xDelta2 = (areaPtr[2] - centerX)/width;
        xDelta2 *= xDelta2;
        yDelta2 = (areaPtr[3] - centerY)/height;
        yDelta2 *= yDelta2;
        if (((xDelta1 + yDelta1) < 1.0)
                && ((xDelta1 + yDelta2) < 1.0)
                && ((xDelta2 + yDelta1) < 1.0)
                && ((xDelta2 + yDelta2) < 1.0)) {
            return -1;
        }
    }
    return result;
}
\f
/*
 *--------------------------------------------------------------
 *
 * ScaleRectOval --
 *
 *      This procedure is invoked to rescale a rectangle or oval
 *      item.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The rectangle or oval 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
ScaleRectOval(canvasPtr, itemPtr, originX, originY, scaleX, scaleY)
    Tk_Canvas *canvasPtr;               /* Canvas containing rectangle. */
    Tk_Item *itemPtr;                   /* Rectangle 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. */
{
    register RectOvalItem *rectOvalPtr = (RectOvalItem *) itemPtr;

    rectOvalPtr->bbox[0] = originX + scaleX*(rectOvalPtr->bbox[0] - originX);
    rectOvalPtr->bbox[1] = originY + scaleY*(rectOvalPtr->bbox[1] - originY);
    rectOvalPtr->bbox[2] = originX + scaleX*(rectOvalPtr->bbox[2] - originX);
    rectOvalPtr->bbox[3] = originY + scaleY*(rectOvalPtr->bbox[3] - originY);
    ComputeRectOvalBbox(canvasPtr, rectOvalPtr);
}
\f
/*
 *--------------------------------------------------------------
 *
 * TranslateRectOval --
 *
 *      This procedure is called to move a rectangle or oval by a
 *      given amount.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      The position of the rectangle or oval is offset by
 *      (xDelta, yDelta), and the bounding box is updated in the
 *      generic part of the item structure.
 *
 *--------------------------------------------------------------
 */

static void
TranslateRectOval(canvasPtr, itemPtr, deltaX, deltaY)
    Tk_Canvas *canvasPtr;               /* Canvas containing item. */
    Tk_Item *itemPtr;                   /* Item that is being moved. */
    double deltaX, deltaY;              /* Amount by which item is to be
                                         * moved. */
{
    register RectOvalItem *rectOvalPtr = (RectOvalItem *) itemPtr;

    rectOvalPtr->bbox[0] += deltaX;
    rectOvalPtr->bbox[1] += deltaY;
    rectOvalPtr->bbox[2] += deltaX;
    rectOvalPtr->bbox[3] += deltaY;
    ComputeRectOvalBbox(canvasPtr, rectOvalPtr);
}