if your using the canvas from the form it is only painting to the video
you need to write to a bitmap to keep your work and then paint it to the
on a onPaint event.
how ever all is not lost..
Timage has a screen canvas and contains a bitmap for you.
drop a timage on the form and use the canvas of that instead.
in short your actually drawing to the picture.bitmap.canvas that is
in Timage, but timage overriders the canvas to always insure that an
invalidate message is sent to windows after your drawing to force it to
paint the contents of the bitmap to the forms surface.
> I'm drawing on an image canvas, (i.e. Canvas->MoveTo(X,Y) and
> Canvas->LineTo(X,Y)) and have a couple of problems-
> 1. The drawing seems a little slow. I am drawing perhaps a few thousand
> lines, and it takes maybe a quarter of a second. Is there a quicker way?
> 2. If the form with the image on which I am drawing looses focus, then
> regains it, all of the drawing is lost. How can I prevent this from
> Many thanks.
> Ian Belchamber
> mobile: +44(0)7802 416525