valuelabelrenderer.java

jCharts是一个100％基于Java的制图工具

	/*************************************************************************************************
	 *
	 * @param axisValueRenderEvent
	 * @param formattedTextTag
	 * @return float
	 ************************************************************************************************/
	private float calculateYHorizontalPlot( AxisValueRenderEvent axisValueRenderEvent,
														 TextTag formattedTextTag )
	{
		float y = axisValueRenderEvent.getValueY();

		if( this.isLabelVertical )
		{
			y += (formattedTextTag.getWidth() / 2);
		}
		else
		{
			y += formattedTextTag.getFontDescent();
		}

		return y;
	}


	/*************************************************************************************************
	 *
	 * @param axisValueRenderEvent
	 * @param formattedTextTag
	 * @param isNegative
	 * @return
	 ************************************************************************************************/
	private float calculateXHorizontalPlot( AxisValueRenderEvent axisValueRenderEvent,
														 TextTag formattedTextTag,
														 boolean isNegative )
	{
		float x = axisValueRenderEvent.getValueX();

		if( this.valueLabelPosition.equals( ValueLabelPosition.ON_TOP ) )
		{
			//---if the value is negative, 'top' is to the left
			if( isNegative )
			{
				x -= (this.isLabelVertical) ? 0 : formattedTextTag.getWidth();
				x -= this.pixelValuePadding;
			}
			else
			{
				x += (this.isLabelVertical) ? formattedTextTag.getFontAscent() : 0;
				x += this.pixelValuePadding;
			}
		}
		else if( this.valueLabelPosition.equals( ValueLabelPosition.AT_TOP ) )
		{
			if( isNegative )
			{
				x += (this.isLabelVertical) ? formattedTextTag.getFontAscent() : 0;
				x += this.pixelValuePadding;
			}
			else
			{
				x -= (this.isLabelVertical) ? formattedTextTag.getFontDescent() : formattedTextTag.getWidth();
				x -= this.pixelValuePadding;
			}
		}
		else if( this.valueLabelPosition.equals( ValueLabelPosition.ABOVE_ZERO_LINE ) )
		{
			x = axisValueRenderEvent.getZeroLineCoordinate();

			if( isNegative )
			{
				x += (this.isLabelVertical) ? formattedTextTag.getFontAscent() : 0;
				x += this.pixelValuePadding;
			}
			else
			{
				x -= (this.isLabelVertical) ? formattedTextTag.getFontDescent() : formattedTextTag.getWidth();
				x -= this.pixelValuePadding;
			}
		}


		else if( this.valueLabelPosition.equals( ValueLabelPosition.AXIS_TOP ) )
		{
			x = axisValueRenderEvent.getTotalItemAxisArea().x + axisValueRenderEvent.getTotalItemAxisArea().width;

			x -= (this.isLabelVertical) ? 0 : formattedTextTag.getWidth();
			x -= this.pixelValuePadding;
		}
		else if( this.valueLabelPosition.equals( ValueLabelPosition.AXIS_BOTTOM ) )
		{
			x = axisValueRenderEvent.getTotalItemAxisArea().x;
			x += (this.isLabelVertical) ? formattedTextTag.getFontAscent() : 0;
			x += this.pixelValuePadding;
		}


		//VALIDATION - force labels into plot area, in case there is a user defined scale.
//todo could we skip this validation for non-user defined scales?
		//---if label goes off the right edge, force it to stay in the plot area.
		if( (x + formattedTextTag.getWidth())
			> (axisValueRenderEvent.getTotalItemAxisArea().x + axisValueRenderEvent.getTotalItemAxisArea().width) )
		{
			x = axisValueRenderEvent.getTotalItemAxisArea().x + axisValueRenderEvent.getTotalItemAxisArea().width;
			x -= formattedTextTag.getWidth();
			x -= this.pixelValuePadding;
		}
		//---if label goes off left edge, force to the right
		else if( x < axisValueRenderEvent.getTotalItemAxisArea().x )
		{
			x = axisValueRenderEvent.getTotalItemAxisArea().x;
			x += this.pixelValuePadding;
		}

		return x;
	}


	/*************************************************************************************************
	 *
	 * @param axisValueRenderEvent
	 * @param formattedTextTag
	 * @param isNegative
	 * @return
	 ************************************************************************************************/
	private float calculateYVerticalPlot( AxisValueRenderEvent axisValueRenderEvent,
													  TextTag formattedTextTag,
													  boolean isNegative )
	{
		float y = axisValueRenderEvent.getValueY();

		if( this.valueLabelPosition.equals( ValueLabelPosition.ON_TOP ) )
		{
			//---if the value is negative, 'top' is to the bottom
			if( isNegative )
			{
				y += (this.isLabelVertical) ? formattedTextTag.getWidth() : formattedTextTag.getHeight();
				y += this.pixelValuePadding;
			}
			else
			{
				y -= this.pixelValuePadding;
			}
		}
		else if( this.valueLabelPosition.equals( ValueLabelPosition.AT_TOP ) )
		{
			//---if the value is negative, 'top' is to the bottom
			if( isNegative )
			{
				y -= this.pixelValuePadding;
			}
			else
			{
				y += (this.isLabelVertical) ? formattedTextTag.getWidth() : formattedTextTag.getHeight();
				y += this.pixelValuePadding;
			}
		}
		else if( this.valueLabelPosition.equals( ValueLabelPosition.ABOVE_ZERO_LINE ) )
		{
			y = axisValueRenderEvent.getZeroLineCoordinate();

			//---if the value is negative, 'top' is to the bottom
			if( isNegative )
			{
				y -= this.pixelValuePadding;
			}
			else
			{
				y += (this.isLabelVertical) ? formattedTextTag.getWidth() : formattedTextTag.getHeight();
				y += this.pixelValuePadding;
			}
		}

		else if( this.valueLabelPosition.equals( ValueLabelPosition.AXIS_TOP ) )
		{
			y = axisValueRenderEvent.getTotalItemAxisArea().y;
			y += (this.isLabelVertical) ? formattedTextTag.getWidth() : formattedTextTag.getHeight();
			y += this.pixelValuePadding;
		}
		else if( this.valueLabelPosition.equals( ValueLabelPosition.AXIS_BOTTOM ) )
		{
			y = axisValueRenderEvent.getTotalItemAxisArea().y + axisValueRenderEvent.getTotalItemAxisArea().height;
			y -= this.pixelValuePadding;
		}



		//VALIDATION - force labels into plot area, in case there is a user defined scale.
		if( isLabelVertical )
		{
			//---if label goes off the bottom edge, force it to stay in the plot area.
			if( ( y - formattedTextTag.getWidth() ) < axisValueRenderEvent.getTotalItemAxisArea().y )
			{
				y = axisValueRenderEvent.getTotalItemAxisArea().y;
				y += formattedTextTag.getWidth();
				y += this.pixelValuePadding;
			}
			//---if label goes off bottom edge, force to the up
			else if( y > axisValueRenderEvent.getTotalItemAxisArea().y + axisValueRenderEvent.getTotalItemAxisArea().height )
			{
				y = axisValueRenderEvent.getTotalItemAxisArea().y + axisValueRenderEvent.getTotalItemAxisArea().height;
				y -= this.pixelValuePadding;
			}
		}
		else
		{
			//---if label goes off the top edge, force it to stay in the plot area.
			if( ( y - formattedTextTag.getHeight() ) < axisValueRenderEvent.getTotalItemAxisArea().y )
			{
				y = axisValueRenderEvent.getTotalItemAxisArea().y;
				y += formattedTextTag.getHeight();
				y += this.pixelValuePadding;
			}
			//---if label goes off bottom edge, force to the up
			else if( y > axisValueRenderEvent.getTotalItemAxisArea().y + axisValueRenderEvent.getTotalItemAxisArea().height )
			{
				y = axisValueRenderEvent.getTotalItemAxisArea().y + axisValueRenderEvent.getTotalItemAxisArea().height;
				y -= this.pixelValuePadding;
			}
		}

		return y;
	}
}