I am using JFreechart to generate some plots, and I found the lines in my plot is blurry, but the demo shows that all the lines are thin and without any blurry, I was wondering
With more information, I can't explain the rendering and resampling artifact illustrated in your question. Starting from MinMaxCategoryPlotDemo1.java
in the demo, I added this line to get the PNG
image shown.
ChartUtilities.saveChartAsPNG(new File("temp.png"), jfreechart, 1024, 768);
In particular,
I chose a larger size, as it's generally better to have more pixels than fewer when resampling.
I chose PNG, a lossless image format used in the MinMaxCategoryRenderer API image.
Click to enlarge: