> If you're trying to go all out and replicate things like phosphor > diffusion, antialiased lines, phosphor burn and fade, and speed > is secondary to that, consider drawing into your own ram buffer > and slapping the ram buffer to the screen using fl_draw_image(). > Example: http://seriss.com/people/erco/fltk/#FlDrawImage > > With this you could just plot points wherever you want, and have > a separate routine that passes over the entire image every 1/10th > of a second (using a timer) that halves all the green pixel values, > simulating a phosphor scope's 'fade'. > > Most modern machines should be fast enough for this. And if you're > only plotting green, then you'd only have to fade the green channel, > so you don't have to spend time considering red + blue pixels.
A colleague of mine did this using OpenGL - in effect he just drew in the new trace on top of the old trace, but with a bit of alpha blending... Gave really nice "fading persistence" effects, and easy to vary the persistence by tweaking the alpha. So that's an option too. But if it's for an ECG simulation, I don't think "persistence" is required, the only time I've seen one up close, the screen was refreshed sweeping slowly left-to-right, and was opaque overwritten, the previous trace did not show through. _______________________________________________ fltk mailing list [email protected] http://lists.easysw.com/mailman/listinfo/fltk
