blocks|key|955272|text|因此，DefaultPolarItemRenderer接收所有极点，将极点转换为常规Java2D坐标，使用这些点生成Polygon，然后绘制它。下面是我如何让它绘制点而不是多边形：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|955273|public+class+MyDefaultPolarItemRenderer+extends+DefaultPolarItemRenderer+{

++++@Override
++++public+void+drawSeries(java.awt.Graphics2D+g2,+java.awt.geom.Rectangle2D+dataArea,+PlotRenderingInfo+info,+PolarPlot+plot,+XYDataset+dataset,+int+seriesIndex)+{


++++++++int+numPoints+=+dataset.getItemCount(seriesIndex);
++++++++for+(int+i+=+0;+i+<+numPoints;+i%2B%2B)+{

++++++++++++double+theta+=+dataset.getXValue(seriesIndex,+i);
++++++++++++double+radius+=+dataset.getYValue(seriesIndex,+i);
++++++++++++Point+p+=+plot.translateValueThetaRadiusToJava2D(theta,+radius,
++++++++++++++++++++dataArea);
++++++++++++Ellipse2D+el+=+new+Ellipse2D.Double(p.x,+p.y,+5,+5);
++++++++++++g2.fill(el);
++++++++++++g2.draw(el);
++++++++}
++++}
}|code-block|syntax|javascript|955274|然后在别处实例化这个类：|955275|++++MyDefaultPolarItemRenderer+dpir+=+new+MyDefaultPolarItemRenderer();
++++dpir.setPlot(plot);
++++plot.setRenderer(dpir);|955276|entityMap^0|3|O|1M|7|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|W|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|P|$]]

So the <code>DefaultPolarItemRenderer</code> takes in all the polar points, converts the polar points to regular Java2D coordinates, makes a <code>Polygon</code> with those points and then draws it. Here's how I got it to draw dots instead of a polygon:

<pre><code>public class MyDefaultPolarItemRenderer extends DefaultPolarItemRenderer {

 @Override
 public void drawSeries(java.awt.Graphics2D g2, java.awt.geom.Rectangle2D dataArea, PlotRenderingInfo info, PolarPlot plot, XYDataset dataset, int seriesIndex) {


 int numPoints = dataset.getItemCount(seriesIndex);
 for (int i = 0; i &lt; numPoints; i++) {

 double theta = dataset.getXValue(seriesIndex, i);
 double radius = dataset.getYValue(seriesIndex, i);
 Point p = plot.translateValueThetaRadiusToJava2D(theta, radius,
 dataArea);
 Ellipse2D el = new Ellipse2D.Double(p.x, p.y, 5, 5);
 g2.fill(el);
 g2.draw(el);
 }
 }
}
</code></pre>

and then instantiated this class elsewhere:

<pre><code> MyDefaultPolarItemRenderer dpir = new MyDefaultPolarItemRenderer();
 dpir.setPlot(plot);
 plot.setRenderer(dpir);
</code></pre>

blocks|key|2789764|text|这是一个很好的讨论，如果您希望该函数拾取用户分配给该系列的颜色|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2789765|添加...|2789766|Color+c+=(Color)this.lookupSeriesPaint(seriesIndex);
g2.setColor(c);|code-block|syntax|javascript|2789767|之前..。|2789768|g.draw(e1);|2789769|还有其他功能..。使用代码完成来查看针对以lookupSeries........(int+seriesindex)开头的名称的系列渲染还提供了哪些函数|offset|length|style|CODE|2789770|entityMap^0|0|0|0|0|0|L|11|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|Z|8|@$O|10|P|11|Q|R]]|9|@]|A|$]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

This is an excellent discussion, in case you want the function to pick up the color assigned by user to the series

add ...

<pre><code>Color c =(Color)this.lookupSeriesPaint(seriesIndex);
g2.setColor(c);
</code></pre>

before ...

<pre><code>g.draw(e1);
</code></pre>

there are other functions... use code completion to see what else functions are available against series rendereing with name starting from <code>lookupSeries........(int seriesindex)</code>

blocks|key|955320|text|我发现了一种相当奇怪的方法来获得这些点，而不需要任何连接它们的线。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|955321|我将renderer的Stroke设置为一条细线，虚线相位为0，长度为1e10：|offset|length|955322|Stroke+dashedStroke+=+new+BasicStroke(
++++++++++++++++++++++++++0.0f,+BasicStroke.CAP_ROUND,+BasicStroke.JOIN_ROUND,
++++++++++++++++++++++++++0.0f,+new+float[]+{0.0f,+1e10f},+1.0f+);
renderer.setSeriesStroke(0,+dashedStroke);|code-block|syntax|javascript|955323|entityMap|0|LINK|mutability|MUTABLE|url|http://www.jfree.org/jfreechart/api/javadoc/org/jfree/chart/renderer/DefaultPolarItemRenderer.html|1|https://docs.oracle.com/javase/7/docs/api/java/awt/BasicStroke.html^0|0|2|8|0|B|6|1|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@$D|W|E|X|1|Y]|$D|Z|E|10|1|11]]|A|$]]|$1|F|3|G|5|H|7|12|8|@]|9|@]|A|$I|J]]|$1|K|3|-4|5|6|7|13|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]|S|$5|N|O|P|A|$Q|T]]]]

I found a rather strange way to get the points without any lines connecting them.

I set the <a href="https://docs.oracle.com/javase/7/docs/api/java/awt/BasicStroke.html" rel="nofollow noreferrer">Stroke</a> of the <a href="http://www.jfree.org/jfreechart/api/javadoc/org/jfree/chart/renderer/DefaultPolarItemRenderer.html" rel="nofollow noreferrer">renderer</a> to be a thin line, with a dash phase of 0, and length of 1e10:

<pre><code>Stroke dashedStroke = new BasicStroke(
 0.0f, BasicStroke.CAP_ROUND, BasicStroke.JOIN_ROUND,
 0.0f, new float[] {0.0f, 1e10f}, 1.0f );
renderer.setSeriesStroke(0, dashedStroke);
</code></pre>

Currently, the PolarChart joins all the coordinates with lines creating a polygon. I just want it to plot each point with a dot and NOT join them together. Is this possible?

I have tried using <code>translateValueThetaRadiusToJava2D()</code> and Graphics2D to draw circles but it's very clunky and contrived.

Any suggestions welcome!

Plot points instead of lines? JFreeChart PolarChart

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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目前，PolarChart使用创建多边形的线连接所有坐标。我只想让它用一个点来绘制每个点，而不是把它们连接在一起。这个是可能的吗？我尝试过使用translateValueThetaRadiusToJava2D()和Graphics2D来画圆，但是它非常笨拙和做作。欢迎任何建议！

问绘制点而不是线？JFreeChart PolarChart
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问绘制点而不是线？JFreeChart PolarChartEN