afreechart/src/main/java/org/afree/chart/plot/Plot.java
/**
     * Fills the specified area with the background paint. If the background
     * paint is an instance of <code>GradientPaint</code>, the gradient will run
     * in the direction suggested by the plot's orientation.
     * 
     * @param canvas
     *            the graphics target.
     * @param area
     *            the plot area.
     * @param orientation
     *            the plot orientation (<code>null</code> not permitted).
     * 
     * @since JFreeChart 1.0.6
     */
Fills the specified area with the background paint. If the background
paint is an instance of GradientPaint, the gradient will run
in the direction suggested by the plot's orientation.

@param canvas
the graphics target.
@param area
the plot area.
@param orientation
the plot orientation (null not permitted).


Fills the specified area with the background paint . If the background paint is an instance of GradientPaint the gradient will run in the direction suggested by the plot ' s orientation . @param canvas the graphics target . @param area the plot area . @param orientation the plot orientation ( null not permitted ) .
protected void fillBackground(Canvas canvas, RectShape area,
            PlotOrientation orientation) {
        if (orientation == null) {
            throw new IllegalArgumentException("Null 'orientation' argument.");
        }
        if (this.backgroundPaintType == null) {
            return;
        }
        Paint p = PaintUtility.createPaint(Paint.ANTI_ALIAS_FLAG, this.backgroundPaintType);
        /*
         * if (p instanceof GradientPaint) { GradientPaint gp = (GradientPaint)
         * p; if (orientation == PlotOrientation.VERTICAL) { p = new
         * GradientPaint((float) area.getCenterX(), (float) area.getMaxY(),
         * gp.getColor1(), (float) area.getCenterX(), (float) area.getMinY(),
         * gp.getColor2()); } else if (orientation ==
         * PlotOrientation.HORIZONTAL) { p = new GradientPaint((float)
         * area.getMinX(), (float) area.getCenterY(), gp.getColor1(), (float)
         * area.getMaxX(), (float) area.getCenterY(), gp.getColor2()); } }
         */
        area.fill(canvas, p);
    }
protected void fillBackground ( Canvas canvas , RectShape area , PlotOrientation orientation ) { if ( orientation == null ) { throw new IllegalArgumentException ( "Null 'orientation' argument." ) ; } if ( this . backgroundPaintType == null ) { return ; } Paint p = PaintUtility . createPaint ( Paint . ANTI_ALIAS_FLAG , this . backgroundPaintType ) ; /*
         * if (p instanceof GradientPaint) { GradientPaint gp = (GradientPaint)
         * p; if (orientation == PlotOrientation.VERTICAL) { p = new
         * GradientPaint((float) area.getCenterX(), (float) area.getMaxY(),
         * gp.getColor1(), (float) area.getCenterX(), (float) area.getMinY(),
         * gp.getColor2()); } else if (orientation ==
         * PlotOrientation.HORIZONTAL) { p = new GradientPaint((float)
         * area.getMinX(), (float) area.getCenterY(), gp.getColor1(), (float)
         * area.getMaxX(), (float) area.getCenterY(), gp.getColor2()); } }
         */ area . fill ( canvas , p ) ; }
Fills the specified area with the background paint.
Fills the specified area with the background paint .