How it works
The idea is to provide a pure ansi/iso c++ plot class (called PPlot).
Of course no actual plotting can be done in c++. The connection to the
graphical world (widgets) is done via an abstract class that you have to
implement. The class is called Painter and asks you to
implement things like
- draw a line from (x1,y1) to (x2,y2)
- draw a text at position (x,y)
- calculate width of a text when drawn on screen
I have implemented the Painter class in QT (a nice c++
framework) and Zinc (an obscure API used in real time computing).
I followed the following strategy to turn a native widget into a
pplot window:
class PPlotNativeWidget: public NativeWidget, public
Painter
{
// implement Painter interface
virtual NativeDraw () { // this is the draw
function of your OS, or portable framework
mPPlot.Draw (*this); // this causes
calls to Painter interface (=drawing!)
}
private:
PPlot mPPlot;// no reason to inherit from
PPlot,rather make it a member
};
You can fill your native widget with an example plot like this
PPlotNativeWidget *a = new PPlotNativeWidget
(x,y,w,h,...)
MakeExamplePlot (1, a->mPPlot); // fill it with one of the
default plots
Pier
