Thank you for your answer; it is very helpful. To make the bitmap work with transparency, it turns out the draw command needs to be: Chart1->Canvas->ReferenceCanvas->Draw(Chart1->ChartRect.Left, Chart1->ChartRect.Top, backChart); In other words, you need to use the ReferenceCanvas, as TTeeCanvas doe...

Hello: Yes, I'm aware that drawing a million lines is always slow. But, when my application needs it, it needs it. The link you provided does not present any solutions I can identify; I can't see anything about reducing the number of lines to draw. To be clear, I am OK with being slow drawing a mill...

Hello, Thanks for your answer. Here is a project (in C++ Builder 11 Update 1) that demonstrates the various aspects of my question. By shift-clicking on the chart, you can move the non-zero point, and cause the chart to redraw. The drop-down list controls how many background lines are drawn. At one ...

I have an application where I use BeforeDrawSeries to draw lines manually (e.g., with MoveTo and LineTo) prior to regular rendering. When there are just tens or hundreds of lines, it works fine, but when there are thousands, it gets bogged down, and so I would like to improve its efficiency. In addi...