archie/tk3.6/tkCanvPoly.c
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/*
* tkCanvPoly.c --
*
* This file implements polygon items for canvas widgets.
*
* Copyright (c) 1991-1993 The Regents of the University of California.
* All rights reserved.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
* OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
* CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
#ifndef lint
static char rcsid[] = "$Header: /user6/ouster/wish/RCS/tkCanvPoly.c,v 1.17 93/09/15 08:19:50 ouster Exp $ SPRITE (Berkeley)";
#endif
#include <stdio.h>
#include "tkInt.h"
#include "tkCanvas.h"
#include "tkConfig.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. */
int numPoints; /* Number of points in polygon (always >= 3).
* 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. */
XColor *fg; /* Foreground color for polygon. */
Pixmap fillStipple; /* Stipple bitmap for filling polygon. */
GC gc; /* Graphics context for filling polygon. */
int smooth; /* Non-zero means draw shape smoothed (i.e.
* with Bezier splines). */
int splineSteps; /* Number of steps in each spline segment. */
} PolygonItem;
/*
* Information used for parsing configuration specs:
*/
static Tk_ConfigSpec configSpecs[] = {
{TK_CONFIG_COLOR, "-fill", (char *) NULL, (char *) NULL,
"black", Tk_Offset(PolygonItem, fg), TK_CONFIG_NULL_OK},
{TK_CONFIG_BOOLEAN, "-smooth", (char *) NULL, (char *) NULL,
"0", Tk_Offset(PolygonItem, smooth), TK_CONFIG_DONT_SET_DEFAULT},
{TK_CONFIG_INT, "-splinesteps", (char *) NULL, (char *) NULL,
"12", Tk_Offset(PolygonItem, splineSteps), TK_CONFIG_DONT_SET_DEFAULT},
{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, &tkCanvasTagsOption},
{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 *canvasPtr,
PolygonItem *polyPtr));
static int ConfigurePolygon _ANSI_ARGS_((
Tk_Canvas *canvasPtr, Tk_Item *itemPtr, int argc,
char **argv, int flags));
static int CreatePolygon _ANSI_ARGS_((Tk_Canvas *canvasPtr,
struct Tk_Item *itemPtr, int argc, char **argv));
static void DeletePolygon _ANSI_ARGS_((Tk_Canvas *canvasPtr,
Tk_Item *itemPtr));
static void DisplayPolygon _ANSI_ARGS_((Tk_Canvas *canvasPtr,
Tk_Item *itemPtr, Drawable dst));
static int PolygonCoords _ANSI_ARGS_((Tk_Canvas *canvasPtr,
Tk_Item *itemPtr, int argc, char **argv));
static int PolygonToArea _ANSI_ARGS_((Tk_Canvas *canvasPtr,
Tk_Item *itemPtr, double *rectPtr));
static double PolygonToPoint _ANSI_ARGS_((Tk_Canvas *canvasPtr,
Tk_Item *itemPtr, double *pointPtr));
static int PolygonToPostscript _ANSI_ARGS_((Tk_Canvas *canvasPtr,
Tk_Item *itemPtr, Tk_PostscriptInfo *psInfoPtr));
static void ScalePolygon _ANSI_ARGS_((Tk_Canvas *canvasPtr,
Tk_Item *itemPtr, double originX, double originY,
double scaleX, double scaleY));
static void TranslatePolygon _ANSI_ARGS_((Tk_Canvas *canvasPtr,
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 */
0, /* alwaysRedraw */
PolygonToPoint, /* pointProc */
PolygonToArea, /* areaProc */
PolygonToPostscript, /* postscriptProc */
ScalePolygon, /* scaleProc */
TranslatePolygon, /* translateProc */
(Tk_ItemIndexProc *) NULL, /* indexProc */
(Tk_ItemCursorProc *) NULL, /* icursorProc */
(Tk_ItemSelectionProc *) NULL, /* selectionProc */
(Tk_ItemInsertProc *) NULL, /* insertProc */
(Tk_ItemDCharsProc *) NULL, /* 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
* canvasPtr->interp->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(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 polygon. */
{
register PolygonItem *polyPtr = (PolygonItem *) itemPtr;
int i;
if (argc < 6) {
Tcl_AppendResult(canvasPtr->interp, "wrong # args: should be \"",
Tk_PathName(canvasPtr->tkwin), "\" create ",
itemPtr->typePtr->name,
" x1 y1 x2 y2 x3 y3 ?x4 y4 ...? ?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.
*/
polyPtr->numPoints = 0;
polyPtr->pointsAllocated = 0;
polyPtr->coordPtr = NULL;
polyPtr->fg = None;
polyPtr->fillStipple = None;
polyPtr->gc = None;
polyPtr->smooth = 0;
polyPtr->splineSteps = 12;
/*
* 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 = 4; i < (argc-1); i+=2) {
if ((!isdigit(UCHAR(argv[i][0]))) &&
((argv[i][0] != '-') || (!isdigit(UCHAR(argv[i][1]))))) {
break;
}
}
if (PolygonCoords(canvasPtr, itemPtr, i, argv) != TCL_OK) {
goto error;
}
if (ConfigurePolygon(canvasPtr, itemPtr, argc-i, argv+i, 0) == TCL_OK) {
return TCL_OK;
}
error:
DeletePolygon(canvasPtr, itemPtr);
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 canvasPtr->interp->result.
*
* Side effects:
* The coordinates for the given item may be changed.
*
*--------------------------------------------------------------
*/
static int
PolygonCoords(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 PolygonItem *polyPtr = (PolygonItem *) itemPtr;
char buffer[TCL_DOUBLE_SPACE];
int i, numPoints;
if (argc == 0) {
for (i = 0; i < 2*polyPtr->numPoints; i++) {
Tcl_PrintDouble(canvasPtr->interp, polyPtr->coordPtr[i], buffer);
Tcl_AppendElement(canvasPtr->interp, buffer);
}
} else if (argc < 6) {
Tcl_AppendResult(canvasPtr->interp,
"too few coordinates for polygon: must have at least 6",
(char *) NULL);
return TCL_ERROR;
} else if (argc & 1) {
Tcl_AppendResult(canvasPtr->interp,
"odd number of coordinates specified for polygon",
(char *) NULL);
return TCL_ERROR;
} else {
numPoints = argc/2;
if (polyPtr->pointsAllocated <= numPoints) {
if (polyPtr->coordPtr != NULL) {
ckfree((char *) polyPtr->coordPtr);
}
/*
* One extra point gets allocated here, just in case we have
* to add another point to close the polygon.
*/
polyPtr->coordPtr = (double *) ckalloc((unsigned)
(sizeof(double) * (argc+2)));
polyPtr->pointsAllocated = polyPtr->numPoints = numPoints;
}
for (i = argc-1; i >= 0; i--) {
if (TkGetCanvasCoord(canvasPtr, argv[i], &polyPtr->coordPtr[i])
!= TCL_OK) {
return TCL_ERROR;
}
}
/*
* Close the polygon if it isn't already closed.
*/
if ((polyPtr->coordPtr[argc-2] != polyPtr->coordPtr[0])
|| (polyPtr->coordPtr[argc-1] != polyPtr->coordPtr[1])) {
polyPtr->numPoints++;
polyPtr->coordPtr[argc] = polyPtr->coordPtr[0];
polyPtr->coordPtr[argc+1] = polyPtr->coordPtr[1];
}
ComputePolygonBbox(canvasPtr, 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 canvasPtr->interp->result.
*
* Side effects:
* Configuration information, such as colors and stipple
* patterns, may be set for itemPtr.
*
*--------------------------------------------------------------
*/
static int
ConfigurePolygon(canvasPtr, itemPtr, argc, argv, flags)
Tk_Canvas *canvasPtr; /* Canvas containing itemPtr. */
Tk_Item *itemPtr; /* Polygon 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 PolygonItem *polyPtr = (PolygonItem *) itemPtr;
XGCValues gcValues;
GC newGC;
unsigned long mask;
if (Tk_ConfigureWidget(canvasPtr->interp, canvasPtr->tkwin,
configSpecs, argc, argv, (char *) polyPtr, flags) != TCL_OK) {
return TCL_ERROR;
}
/*
* A few of the options require additional processing, such as
* graphics contexts.
*/
if (polyPtr->fg == NULL) {
newGC = None;
} else {
gcValues.foreground = polyPtr->fg->pixel;
mask = GCForeground;
if (polyPtr->fillStipple != None) {
gcValues.stipple = polyPtr->fillStipple;
gcValues.fill_style = FillStippled;
mask |= GCStipple|GCFillStyle;
}
newGC = Tk_GetGC(canvasPtr->tkwin, mask, &gcValues);
}
if (polyPtr->gc != None) {
Tk_FreeGC(canvasPtr->display, polyPtr->gc);
}
polyPtr->gc = newGC;
/*
* Keep spline parameters within reasonable limits.
*/
if (polyPtr->splineSteps < 1) {
polyPtr->splineSteps = 1;
} else if (polyPtr->splineSteps > 100) {
polyPtr->splineSteps = 100;
}
ComputePolygonBbox(canvasPtr, 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(canvasPtr, itemPtr)
Tk_Canvas *canvasPtr; /* Info about overall canvas widget. */
Tk_Item *itemPtr; /* Item that is being deleted. */
{
register PolygonItem *polyPtr = (PolygonItem *) itemPtr;
if (polyPtr->coordPtr != NULL) {
ckfree((char *) polyPtr->coordPtr);
}
if (polyPtr->fg != NULL) {
Tk_FreeColor(polyPtr->fg);
}
if (polyPtr->fillStipple != None) {
Tk_FreeBitmap(canvasPtr->display, polyPtr->fillStipple);
}
if (polyPtr->gc != None) {
Tk_FreeGC(canvasPtr->display, polyPtr->gc);
}
}
/*
*--------------------------------------------------------------
*
* 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(canvasPtr, polyPtr)
register Tk_Canvas *canvasPtr; /* Canvas that contains item. */
PolygonItem *polyPtr; /* Item whose bbox is to be
* recomputed. */
{
register double *coordPtr;
int i;
coordPtr = polyPtr->coordPtr;
polyPtr->header.x1 = polyPtr->header.x2 = *coordPtr;
polyPtr->header.y1 = polyPtr->header.y2 = coordPtr[1];
for (i = 1, coordPtr = polyPtr->coordPtr+2; i < polyPtr->numPoints;
i++, coordPtr += 2) {
TkIncludePoint(canvasPtr, (Tk_Item *) polyPtr, coordPtr);
}
/*
* 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 canvasPtr.
*
*--------------------------------------------------------------
*/
void
TkFillPolygon(canvasPtr, coordPtr, numPoints, drawable, gc)
register Tk_Canvas *canvasPtr; /* 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. */
Drawable drawable; /* Pixmap or window in which to draw
* polygon. */
GC gc; /* Graphics context for drawing. */
{
XPoint staticPoints[MAX_STATIC_POINTS];
XPoint *pointPtr;
register 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++) {
pPtr->x = SCREEN_X(canvasPtr, coordPtr[0]);
pPtr->y = SCREEN_Y(canvasPtr, coordPtr[1]);
}
/*
* Display polygon, then free up polygon storage if it was dynamically
* allocated.
*/
XFillPolygon(Tk_Display(canvasPtr->tkwin), drawable, gc, pointPtr,
numPoints, Complex, 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 canvasPtr.
*
*--------------------------------------------------------------
*/
static void
DisplayPolygon(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 PolygonItem *polyPtr = (PolygonItem *) itemPtr;
if (polyPtr->gc == None) {
return;
}
/*
* 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 (polyPtr->fillStipple != None) {
XSetTSOrigin(Tk_Display(canvasPtr->tkwin), polyPtr->gc,
-canvasPtr->drawableXOrigin, -canvasPtr->drawableYOrigin);
}
if (!polyPtr->smooth) {
TkFillPolygon(canvasPtr, polyPtr->coordPtr, polyPtr->numPoints,
drawable, polyPtr->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 = 1 + polyPtr->numPoints*polyPtr->splineSteps;
if (numPoints <= MAX_STATIC_POINTS) {
pointPtr = staticPoints;
} else {
pointPtr = (XPoint *) ckalloc((unsigned)
(numPoints * sizeof(XPoint)));
}
numPoints = TkMakeBezierCurve(canvasPtr, polyPtr->coordPtr,
polyPtr->numPoints, polyPtr->splineSteps, pointPtr,
(double *) NULL);
XFillPolygon(Tk_Display(canvasPtr->tkwin), drawable, polyPtr->gc,
pointPtr, numPoints, Complex, CoordModeOrigin);
if (pointPtr != staticPoints) {
ckfree((char *) pointPtr);
}
}
if (polyPtr->fillStipple != None) {
XSetTSOrigin(Tk_Display(canvasPtr->tkwin), polyPtr->gc, 0, 0);
}
}
/*
*--------------------------------------------------------------
*
* 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(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. */
{
PolygonItem *polyPtr = (PolygonItem *) itemPtr;
double *coordPtr, distance;
double staticSpace[2*MAX_STATIC_POINTS];
int numPoints;
if (!polyPtr->smooth) {
return TkPolygonToPoint(polyPtr->coordPtr, polyPtr->numPoints,
pointPtr);
}
/*
* Smoothed polygon. Generate a new set of points and use them
* for comparison.
*/
numPoints = 1 + polyPtr->numPoints*polyPtr->splineSteps;
if (numPoints <= MAX_STATIC_POINTS) {
coordPtr = staticSpace;
} else {
coordPtr = (double *) ckalloc((unsigned)
(2*numPoints*sizeof(double)));
}
numPoints = TkMakeBezierCurve(canvasPtr, polyPtr->coordPtr,
polyPtr->numPoints, polyPtr->splineSteps, (XPoint *) NULL,
coordPtr);
distance = TkPolygonToPoint(coordPtr, numPoints, pointPtr);
if (coordPtr != staticSpace) {
ckfree((char *) coordPtr);
}
return distance;
}
/*
*--------------------------------------------------------------
*
* 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(canvasPtr, itemPtr, rectPtr)
Tk_Canvas *canvasPtr; /* 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];
int numPoints, result;
if (!polyPtr->smooth) {
return TkPolygonToArea(polyPtr->coordPtr, polyPtr->numPoints, rectPtr);
}
/*
* Smoothed polygon. Generate a new set of points and use them
* for comparison.
*/
numPoints = 1 + polyPtr->numPoints*polyPtr->splineSteps;
if (numPoints <= MAX_STATIC_POINTS) {
coordPtr = staticSpace;
} else {
coordPtr = (double *) ckalloc((unsigned)
(2*numPoints*sizeof(double)));
}
numPoints = TkMakeBezierCurve(canvasPtr, polyPtr->coordPtr,
polyPtr->numPoints, polyPtr->splineSteps, (XPoint *) NULL,
coordPtr);
result = TkPolygonToArea(coordPtr, numPoints, rectPtr);
if (coordPtr != staticSpace) {
ckfree((char *) coordPtr);
}
return result;
}
/*
*--------------------------------------------------------------
*
* 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(canvasPtr, itemPtr, originX, originY, scaleX, scaleY)
Tk_Canvas *canvasPtr; /* 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;
register 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(canvasPtr, polyPtr);
}
/*
*--------------------------------------------------------------
*
* 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(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. */
{
PolygonItem *polyPtr = (PolygonItem *) itemPtr;
register double *coordPtr;
int i;
for (i = 0, coordPtr = polyPtr->coordPtr; i < polyPtr->numPoints;
i++, coordPtr += 2) {
*coordPtr += deltaX;
coordPtr[1] += deltaY;
}
ComputePolygonBbox(canvasPtr, 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 canvasPtr->interp->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(canvasPtr, itemPtr, psInfoPtr)
Tk_Canvas *canvasPtr; /* Information about overall canvas. */
Tk_Item *itemPtr; /* Item for which Postscript is
* wanted. */
Tk_PostscriptInfo *psInfoPtr; /* Information about the Postscript;
* must be passed back to Postscript
* utility procedures. */
{
register PolygonItem *polyPtr = (PolygonItem *) itemPtr;
if (polyPtr->fg == NULL) {
return TCL_OK;
}
/*
* Generate a path for the polygon's outline (do this differently
* for smoothed and linear polygons).
*/
if (!polyPtr->smooth) {
TkCanvPsPath(canvasPtr->interp, polyPtr->coordPtr,
polyPtr->numPoints, psInfoPtr);
} else {
TkMakeBezierPostscript(canvasPtr->interp, polyPtr->coordPtr,
polyPtr->numPoints, psInfoPtr);
}
/*
* Fill the area of the polygon.
*/
if (TkCanvPsColor(canvasPtr, psInfoPtr, polyPtr->fg) != TCL_OK) {
return TCL_ERROR;
};
if (polyPtr->fillStipple != None) {
if (TkCanvPsStipple(canvasPtr, psInfoPtr, polyPtr->fillStipple, 1)
!= TCL_OK) {
return TCL_ERROR;
}
} else {
Tcl_AppendResult(canvasPtr->interp, "eofill\n", (char *) NULL);
}
return TCL_OK;
}