tkcanvbmap.c

linux系统下的音频通信

	case TK_ANCHOR_S:
	    x -= width/2;
	    y -= height;
	    break;
	case TK_ANCHOR_SW:
	    y -= height;
	    break;
	case TK_ANCHOR_W:
	    y -= height/2;
	    break;
	case TK_ANCHOR_NW:
	    break;
	case TK_ANCHOR_CENTER:
	    x -= width/2;
	    y -= height/2;
	    break;
    }

    /*
     * Store the information in the item header.
     */

    bmapPtr->header.x1 = x;
    bmapPtr->header.y1 = y;
    bmapPtr->header.x2 = x + width;
    bmapPtr->header.y2 = y + height;
}

/*
 *--------------------------------------------------------------
 *
 * DisplayBitmap --
 *
 *	This procedure is invoked to draw a bitmap item in a given
 *	drawable.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	ItemPtr is drawn in drawable using the transformation
 *	information in canvas.
 *
 *--------------------------------------------------------------
 */

static void
DisplayBitmap(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). */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    int bmapX, bmapY, bmapWidth, bmapHeight;
    short drawableX, drawableY;

    /*
     * If the area being displayed doesn't cover the whole bitmap,
     * then only redisplay the part of the bitmap that needs
     * redisplay.
     */

    if (bmapPtr->bitmap != None) {
	if (x > bmapPtr->header.x1) {
	    bmapX = x - bmapPtr->header.x1;
	    bmapWidth = bmapPtr->header.x2 - x;
	} else {
	    bmapX = 0;
	    if ((x+width) < bmapPtr->header.x2) {
		bmapWidth = x + width - bmapPtr->header.x1;
	    } else {
		bmapWidth = bmapPtr->header.x2 - bmapPtr->header.x1;
	    }
	}
	if (y > bmapPtr->header.y1) {
	    bmapY = y - bmapPtr->header.y1;
	    bmapHeight = bmapPtr->header.y2 - y;
	} else {
	    bmapY = 0;
	    if ((y+height) < bmapPtr->header.y2) {
		bmapHeight = y + height - bmapPtr->header.y1;
	    } else {
		bmapHeight = bmapPtr->header.y2 - bmapPtr->header.y1;
	    }
	}
	Tk_CanvasDrawableCoords(canvas,
		(double) (bmapPtr->header.x1 + bmapX),
		(double) (bmapPtr->header.y1 + bmapY),
		&drawableX, &drawableY);

	/*
	 * Must modify the mask origin within the graphics context
	 * to line up with the bitmap's origin (in order to make
	 * bitmaps with "-background {}" work right).
	 */
 
	XSetClipOrigin(display, bmapPtr->gc, drawableX - bmapX,
		drawableY - bmapY);
	XCopyPlane(display, bmapPtr->bitmap, drawable,
		bmapPtr->gc, bmapX, bmapY, (unsigned int) bmapWidth,
		(unsigned int) bmapHeight, drawableX, drawableY, 1);
    }
}

/*
 *--------------------------------------------------------------
 *
 * BitmapToPoint --
 *
 *	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 bitmap.  If the
 *	point isn't inside the bitmap then the return value is the
 *	distance from the point to the bitmap.
 *
 * Side effects:
 *	None.
 *
 *--------------------------------------------------------------
 */

	/* ARGSUSED */
static double
BitmapToPoint(canvas, itemPtr, coordPtr)
    Tk_Canvas canvas;		/* Canvas containing item. */
    Tk_Item *itemPtr;		/* Item to check against point. */
    double *coordPtr;		/* Pointer to x and y coordinates. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    double x1, x2, y1, y2, xDiff, yDiff;

    x1 = bmapPtr->header.x1;
    y1 = bmapPtr->header.y1;
    x2 = bmapPtr->header.x2;
    y2 = bmapPtr->header.y2;

    /*
     * Point is outside rectangle.
     */

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

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

    return hypot(xDiff, yDiff);
}

/*
 *--------------------------------------------------------------
 *
 * BitmapToArea --
 *
 *	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
BitmapToArea(canvas, itemPtr, rectPtr)
    Tk_Canvas canvas;		/* Canvas containing item. */
    Tk_Item *itemPtr;		/* Item to check against rectangle. */
    double *rectPtr;		/* Pointer to array of four coordinates
				 * (x1, y1, x2, y2) describing rectangular
				 * area.  */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    if ((rectPtr[2] <= bmapPtr->header.x1)
	    || (rectPtr[0] >= bmapPtr->header.x2)
	    || (rectPtr[3] <= bmapPtr->header.y1)
	    || (rectPtr[1] >= bmapPtr->header.y2)) {
	return -1;
    }
    if ((rectPtr[0] <= bmapPtr->header.x1)
	    && (rectPtr[1] <= bmapPtr->header.y1)
	    && (rectPtr[2] >= bmapPtr->header.x2)
	    && (rectPtr[3] >= bmapPtr->header.y2)) {
	return 1;
    }
    return 0;
}

/*
 *--------------------------------------------------------------
 *
 * ScaleBitmap --
 *
 *	This procedure is invoked to rescale a bitmap item in a
 *	canvas.  It is one of the standard item procedures for
 *	bitmap items, and is invoked by the generic canvas code.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The item 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
ScaleBitmap(canvas, itemPtr, originX, originY, scaleX, scaleY)
    Tk_Canvas canvas;			/* Canvas containing rectangle. */
    Tk_Item *itemPtr;			/* Rectangle to be scaled. */
    double originX, originY;		/* Origin about which to scale item. */
    double scaleX;			/* Amount to scale in X direction. */
    double scaleY;			/* Amount to scale in Y direction. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    bmapPtr->x = originX + scaleX*(bmapPtr->x - originX);
    bmapPtr->y = originY + scaleY*(bmapPtr->y - originY);
    ComputeBitmapBbox(canvas, bmapPtr);
}

/*
 *--------------------------------------------------------------
 *
 * TranslateBitmap --
 *
 *	This procedure is called to move an item by a given amount.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The position of the item is offset by (xDelta, yDelta), and
 *	the bounding box is updated in the generic part of the item
 *	structure.
 *
 *--------------------------------------------------------------
 */

static void
TranslateBitmap(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. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;

    bmapPtr->x += deltaX;
    bmapPtr->y += deltaY;
    ComputeBitmapBbox(canvas, bmapPtr);
}

/*
 *--------------------------------------------------------------
 *
 * BitmapToPostscript --
 *
 *	This procedure is called to generate Postscript for
 *	bitmap items.
 *
 * Results:
 *	The return value is a standard Tcl result.  If an error
 *	occurs in generating Postscript then an error message is
 *	left in 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
BitmapToPostscript(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. */
{
    BitmapItem *bmapPtr = (BitmapItem *) itemPtr;
    double x, y;
    int width, height, rowsAtOnce, rowsThisTime;
    int curRow;
    char buffer[200];

    if (bmapPtr->bitmap == None) {
	return TCL_OK;
    }

    /*
     * Compute the coordinates of the lower-left corner of the bitmap,
     * taking into account the anchor position for the bitmp.
     */

    x = bmapPtr->x;
    y = Tk_CanvasPsY(canvas, bmapPtr->y);
    Tk_SizeOfBitmap(Tk_Display(Tk_CanvasTkwin(canvas)), bmapPtr->bitmap,
	    &width, &height);
    switch (bmapPtr->anchor) {
	case TK_ANCHOR_NW:			y -= height;		break;
	case TK_ANCHOR_N:	x -= width/2.0; y -= height;		break;
	case TK_ANCHOR_NE:	x -= width;	y -= height;		break;
	case TK_ANCHOR_E:	x -= width;	y -= height/2.0;	break;
	case TK_ANCHOR_SE:	x -= width;				break;
	case TK_ANCHOR_S:	x -= width/2.0;				break;
	case TK_ANCHOR_SW:						break;
	case TK_ANCHOR_W:			y -= height/2.0;	break;
	case TK_ANCHOR_CENTER:	x -= width/2.0; y -= height/2.0;	break;
    }

    /*
     * Color the background, if there is one.
     */

    if (bmapPtr->bgColor != NULL) {
	sprintf(buffer,
		"%.15g %.15g moveto %d 0 rlineto 0 %d rlineto %d %s\n",
		x, y, width, height, -width,"0 rlineto closepath");
	Tcl_AppendResult(interp, buffer, (char *) NULL);
	if (Tk_CanvasPsColor(interp, canvas, bmapPtr->bgColor) != TCL_OK) {
	    return TCL_ERROR;
	}
	Tcl_AppendResult(interp, "fill\n", (char *) NULL);
    }

    /*
     * Draw the bitmap, if there is a foreground color.  If the bitmap
     * is very large, then chop it up into multiple bitmaps, each
     * consisting of one or more rows.  This is needed because Postscript
     * can't handle single strings longer than 64 KBytes long.
     */

    if (bmapPtr->fgColor != NULL) {
	if (Tk_CanvasPsColor(interp, canvas, bmapPtr->fgColor) != TCL_OK) {
	    return TCL_ERROR;
	}
	if (width > 60000) {
	    Tcl_ResetResult(interp);
	    Tcl_AppendResult(interp, "can't generate Postscript",
		    " for bitmaps more than 60000 pixels wide",
		    (char *) NULL);
	    return TCL_ERROR;
	}
	rowsAtOnce = 60000/width;
	if (rowsAtOnce < 1) {
	    rowsAtOnce = 1;
	}
	sprintf(buffer, "%.15g %.15g translate\n", x, y+height);
	Tcl_AppendResult(interp, buffer, (char *) NULL);
	for (curRow = 0; curRow < height; curRow += rowsAtOnce) {
	    rowsThisTime = rowsAtOnce;
	    if (rowsThisTime > (height - curRow)) {
		rowsThisTime = height - curRow;
	    }
	    sprintf(buffer, "0 -%.15g translate\n%d %d true matrix {\n",
		    (double) rowsThisTime, width, rowsThisTime);
	    Tcl_AppendResult(interp, buffer, (char *) NULL);
	    if (Tk_CanvasPsBitmap(interp, canvas, bmapPtr->bitmap,
		    0, curRow, width, rowsThisTime) != TCL_OK) {
		return TCL_ERROR;
	    }
	    Tcl_AppendResult(interp, "\n} imagemask\n", (char *) NULL);
	}
    }
    return TCL_OK;
}