tkcanvarc.c

linux系统下的音频通信

    }
    if (arcPtr->fillGC != None) {
	Tk_FreeGC(Tk_Display(tkwin), arcPtr->fillGC);
    }
    arcPtr->fillGC = newGC;

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

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

    if (arcPtr->numOutlinePoints != 0) {
	ckfree((char *) arcPtr->outlinePtr);
    }
    if (arcPtr->outlineColor != NULL) {
	Tk_FreeColor(arcPtr->outlineColor);
    }
    if (arcPtr->fillColor != NULL) {
	Tk_FreeColor(arcPtr->fillColor);
    }
    if (arcPtr->fillStipple != None) {
	Tk_FreeBitmap(display, arcPtr->fillStipple);
    }
    if (arcPtr->outlineStipple != None) {
	Tk_FreeBitmap(display, arcPtr->outlineStipple);
    }
    if (arcPtr->outlineGC != None) {
	Tk_FreeGC(display, arcPtr->outlineGC);
    }
    if (arcPtr->fillGC != None) {
	Tk_FreeGC(display, arcPtr->fillGC);
    }
}

/*
 *--------------------------------------------------------------
 *
 * ComputeArcBbox --
 *
 *	This procedure is invoked to compute the bounding box of
 *	all the pixels that may be drawn as part of an arc.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The fields x1, y1, x2, and y2 are updated in the header
 *	for itemPtr.
 *
 *--------------------------------------------------------------
 */

	/* ARGSUSED */
static void
ComputeArcBbox(canvas, arcPtr)
    Tk_Canvas canvas;			/* Canvas that contains item. */
    ArcItem *arcPtr;			/* Item whose bbox is to be
					 * recomputed. */
{
    double tmp, center[2], point[2];

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

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

    ComputeArcOutline(arcPtr);

    /*
     * To compute the bounding box, start with the the bbox formed
     * by the two endpoints of the arc.  Then add in the center of
     * the arc's oval (if relevant) and the 3-o'clock, 6-o'clock,
     * 9-o'clock, and 12-o'clock positions, if they are relevant.
     */

    arcPtr->header.x1 = arcPtr->header.x2 = (int) arcPtr->center1[0];
    arcPtr->header.y1 = arcPtr->header.y2 = (int) arcPtr->center1[1];
    TkIncludePoint((Tk_Item *) arcPtr, arcPtr->center2);
    center[0] = (arcPtr->bbox[0] + arcPtr->bbox[2])/2;
    center[1] = (arcPtr->bbox[1] + arcPtr->bbox[3])/2;
    if (arcPtr->style == pieSliceUid) {
	TkIncludePoint((Tk_Item *) arcPtr, center);
    }

    tmp = -arcPtr->start;
    if (tmp < 0) {
	tmp += 360.0;
    }
    if ((tmp < arcPtr->extent) || ((tmp-360) > arcPtr->extent)) {
	point[0] = arcPtr->bbox[2];
	point[1] = center[1];
	TkIncludePoint((Tk_Item *) arcPtr, point);
    }
    tmp = 90.0 - arcPtr->start;
    if (tmp < 0) {
	tmp += 360.0;
    }
    if ((tmp < arcPtr->extent) || ((tmp-360) > arcPtr->extent)) {
	point[0] = center[0];
	point[1] = arcPtr->bbox[1];
	TkIncludePoint((Tk_Item *) arcPtr, point);
    }
    tmp = 180.0 - arcPtr->start;
    if (tmp < 0) {
	tmp += 360.0;
    }
    if ((tmp < arcPtr->extent) || ((tmp-360) > arcPtr->extent)) {
	point[0] = arcPtr->bbox[0];
	point[1] = center[1];
	TkIncludePoint((Tk_Item *) arcPtr, point);
    }
    tmp = 270.0 - arcPtr->start;
    if (tmp < 0) {
	tmp += 360.0;
    }
    if ((tmp < arcPtr->extent) || ((tmp-360) > arcPtr->extent)) {
	point[0] = center[0];
	point[1] = arcPtr->bbox[3];
	TkIncludePoint((Tk_Item *) arcPtr, point);
    }

    /*
     * Lastly, expand by the width of the arc (if the arc's outline is
     * being drawn) and add one extra pixel just for safety.
     */

    if (arcPtr->outlineColor == NULL) {
	tmp = 1;
    } else {
	tmp = (arcPtr->width + 1)/2 + 1;
    }
    arcPtr->header.x1 -= (int) tmp;
    arcPtr->header.y1 -= (int) tmp;
    arcPtr->header.x2 += (int) tmp;
    arcPtr->header.y2 += (int) tmp;
}

/*
 *--------------------------------------------------------------
 *
 * DisplayArc --
 *
 *	This procedure is invoked to draw an arc item in a given
 *	drawable.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	ItemPtr is drawn in drawable using the transformation
 *	information in canvas.
 *
 *--------------------------------------------------------------
 */

static void
DisplayArc(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). */
{
    ArcItem *arcPtr = (ArcItem *) itemPtr;
    short x1, y1, x2, y2;
    int start, extent;

    /*
     * Compute the screen coordinates of the bounding box for the item,
     * plus integer values for the angles.
     */

    Tk_CanvasDrawableCoords(canvas, arcPtr->bbox[0], arcPtr->bbox[1],
	    &x1, &y1);
    Tk_CanvasDrawableCoords(canvas, arcPtr->bbox[2], arcPtr->bbox[3],
	    &x2, &y2);
    if (x2 <= x1) {
	x2 = x1+1;
    }
    if (y2 <= y1) {
	y2 = y1+1;
    }
    start = (int) ((64*arcPtr->start) + 0.5);
    extent = (int) ((64*arcPtr->extent) + 0.5);

    /*
     * Display filled arc first (if wanted), then outline.  If the extent
     * is zero then don't invoke XFillArc or XDrawArc, since this causes
     * some window servers to crash and should be a no-op anyway.
     */

    if ((arcPtr->fillGC != None) && (extent != 0)) {
	if (arcPtr->fillStipple != None) {
	    Tk_CanvasSetStippleOrigin(canvas, arcPtr->fillGC);
	}
	XFillArc(display, drawable, arcPtr->fillGC, x1, y1, (unsigned) (x2-x1),
		(unsigned) (y2-y1), start, extent);
	if (arcPtr->fillStipple != None) {
	    XSetTSOrigin(display, arcPtr->fillGC, 0, 0);
	}
    }
    if (arcPtr->outlineGC != None) {
	if (arcPtr->outlineStipple != None) {
	    Tk_CanvasSetStippleOrigin(canvas, arcPtr->outlineGC);
	}
	if (extent != 0) {
	    XDrawArc(display, drawable, arcPtr->outlineGC, x1, y1,
		    (unsigned) (x2-x1), (unsigned) (y2-y1), start, extent);
	}

	/*
	 * If the outline width is very thin, don't use polygons to draw
	 * the linear parts of the outline (this often results in nothing
	 * being displayed); just draw lines instead.
	 */

	if (arcPtr->width <= 2) {
	    Tk_CanvasDrawableCoords(canvas, arcPtr->center1[0],
		    arcPtr->center1[1], &x1, &y1);
	    Tk_CanvasDrawableCoords(canvas, arcPtr->center2[0],
		    arcPtr->center2[1], &x2, &y2);

	    if (arcPtr->style == chordUid) {
		XDrawLine(display, drawable, arcPtr->outlineGC,
			x1, y1, x2, y2);
	    } else if (arcPtr->style == pieSliceUid) {
		short cx, cy;

		Tk_CanvasDrawableCoords(canvas,
			(arcPtr->bbox[0] + arcPtr->bbox[2])/2.0,
			(arcPtr->bbox[1] + arcPtr->bbox[3])/2.0, &cx, &cy);
		XDrawLine(display, drawable, arcPtr->outlineGC,
			cx, cy, x1, y1);
		XDrawLine(display, drawable, arcPtr->outlineGC,
			cx, cy, x2, y2);
	    }
	} else {
	    if (arcPtr->style == chordUid) {
		TkFillPolygon(canvas, arcPtr->outlinePtr, CHORD_OUTLINE_PTS,
			display, drawable, arcPtr->outlineGC, None);
	    } else if (arcPtr->style == pieSliceUid) {
		TkFillPolygon(canvas, arcPtr->outlinePtr, PIE_OUTLINE1_PTS,
			display, drawable, arcPtr->outlineGC, None);
		TkFillPolygon(canvas, arcPtr->outlinePtr + 2*PIE_OUTLINE1_PTS,
			PIE_OUTLINE2_PTS, display, drawable, arcPtr->outlineGC,
			None);
	    }
	}
	if (arcPtr->outlineStipple != None) {
	    XSetTSOrigin(display, arcPtr->outlineGC, 0, 0);
	}
    }
}

/*
 *--------------------------------------------------------------
 *
 * ArcToPoint --
 *
 *	Computes the distance from a given point to a given
 *	arc, 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 arc.  If the
 *	point isn't inside the arc then the return value is the
 *	distance from the point to the arc.  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
ArcToPoint(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. */
{
    ArcItem *arcPtr = (ArcItem *) itemPtr;
    double vertex[2], pointAngle, diff, dist, newDist;
    double poly[8], polyDist, width, t1, t2;
    int filled, angleInRange;

    /*
     * See if the point is within the angular range of the arc.
     * Remember, X angles are backwards from the way we'd normally
     * think of them.  Also, compensate for any eccentricity of
     * the oval.
     */

    vertex[0] = (arcPtr->bbox[0] + arcPtr->bbox[2])/2.0;
    vertex[1] = (arcPtr->bbox[1] + arcPtr->bbox[3])/2.0;
    t1 = (pointPtr[1] - vertex[1])/(arcPtr->bbox[3] - arcPtr->bbox[1]);
    t2 = (pointPtr[0] - vertex[0])/(arcPtr->bbox[2] - arcPtr->bbox[0]);
    if ((t1 == 0.0) && (t2 == 0.0)) {
	pointAngle = 0;
    } else {
	pointAngle = -atan2(t1, t2)*180/PI;
    }
    diff = pointAngle - arcPtr->start;
    diff -= ((int) (diff/360.0) * 360.0);
    if (diff < 0) {
	diff += 360.0;
    }
    angleInRange = (diff <= arcPtr->extent) ||
	    ((arcPtr->extent < 0) && ((diff - 360.0) >= arcPtr->extent));

    /*
     * Now perform different tests depending on what kind of arc
     * we're dealing with.
     */

    if (arcPtr->style == arcUid) {
	if (angleInRange) {
	    return TkOvalToPoint(arcPtr->bbox, (double) arcPtr->width,
		    0, pointPtr);
	}
	dist = hypot(pointPtr[0] - arcPtr->center1[0],
		pointPtr[1] - arcPtr->center1[1]);
	newDist = hypot(pointPtr[0] - arcPtr->center2[0],
		pointPtr[1] - arcPtr->center2[1]);
	if (newDist < dist) {
	    return newDist;
	}
	return dist;
    }

    if ((arcPtr->fillGC != None) || (arcPtr->outlineGC == None)) {
	filled = 1;
    } else {
	filled = 0;
    }
    if (arcPtr->outlineGC == None) {
	width = 0.0;
    } else {
	width = arcPtr->width;
    }

    if (arcPtr->style == pieSliceUid) {
	if (width > 1.0) {
	    dist = TkPolygonToPoint(arcPtr->outlinePtr, PIE_OUTLINE1_PTS,
		    pointPtr);
	    newDist = TkPolygonToPoint(arcPtr->outlinePtr + 2*PIE_OUTLINE1_PTS,
			PIE_OUTLINE2_PTS, pointPtr);
	} else {
	    dist = TkLineToPoint(vertex, arcPtr->center1, pointPtr);
	    newDist = TkLineToPoint(vertex, arcPtr->center2, pointPtr);
	}
	if (newDist < dist) {
	    dist = newDist;
	}
	if (angleInRange) {
	    newDist = TkOvalToPoint(arcPtr->bbox, width, filled, pointPtr);
	    if (newDist < dist) {
		dist = newDist;
	    }
	}
	return dist;
    }

    /*
     * This is a chord-style arc.  We have to deal specially with the
     * triangular piece that represents the difference between a
     * chord-style arc and a pie-slice arc (for small angles this piece
     * is excluded here where it would be included for pie slices;
     * for large angles the piece is included here but would be
     * excluded for pie slices).
     */

    if (width > 1.0) {
	dist = TkPolygonToPoint(arcPtr->outlinePtr, CHORD_OUTLINE_PTS,
		    pointPtr);
    } else {
	dist = TkLineToPoint(arcPtr->center1, arcPtr->center2, pointPtr);
    }
    poly[0] = poly[6] = vertex[0];
    poly[1] = poly[7] = vertex[1];
    poly[2] = arcPtr->center1[0];
    poly[3] = arcPtr->center1[1];
    poly[4] = arcPtr->center2[0];
    poly[5] = arcPtr->center2[1];
    polyDist = TkPolygonToPoint(poly, 4, pointPtr);
    if (angleInRange) {
	if ((arcPtr->extent < -180.0) || (arcPtr->extent > 180.0)
		|| (polyDist > 0.0)) {