On Fri, 30 Sep 2005 14:38:37 -0300
Felipe Monteiro de Carvalho <[EMAIL PROTECTED]> wrote:
> > I would not use any graphic control to do fast drawing but instead a
> > window based control such as TPanel or create my own with an internal
> > canvas, however for making an Osciloscope i would certainly use
> > dedicated libraries such as SDL or OpenGL, you may try the GLScene
> > components, with this kind of libs you can easily get hundreds of
> > frames and they are not so bad to setup, not to mention that you have
> > specific drawing funcs for various shapes and all kinds of goodies and
> > they are CrossPlatform you can even use a Panel to render using
> > OpenGL.
> >
> > Razvan
>
> Thanks, but the Osciloscope is being implemented on an ISA card and such
> BUS only exists on old computers. The GUI will be running on something
> like a Pentium 233 Mhz, but I may even try to get it running on older
> computers, so no OpenGL ;)
>
> The idea of creating a custom control seams very good. Can it really
> improve the drawing speed? why?
There is no speed gain between a custum control using the paint event of a
form/panel/paintbox/image.
Only drawing on a TImage picture is slow.
You can gain speed with opengl or other direct access functions, but you can
use them for any control. Creating a custom control has the advantage of
structuring your code. You can reuse the control.
> About the drawing function, I won't use anything fancy. My tasks are
> more programming oriented than graphics oriented, like finding the
> Fourier Series of the wave and drawing it. It's just a plotting of many
> dots and lines. Curves can be made with the dots and lines.
Mattias
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