At Thu, 30 Aug 2001 14:03:36 -0700 (PDT),
David A. Desrosiers <[EMAIL PROTECTED]> wrote:
> > It is difficult currently. Once the page is drawn, its just a long bunch
> > of pixels. A scrollbar for showing the position in the long bunch of
> > pixels needs to be calculated also, which would require doing the
> > calculations anyways. If you have an answer though, by all means pass it
> > along, it would provide functionality for a copy text also.
>
> Right now, the height of the displayed page is recalculated when you
> scroll up or down using the chevrons on the scrollbar as I understand it (to
> account for cases where you turn on different features, turn off images,
> etc.). That's something we have to be careful of as well, when we disable
> images, change the font size/height, and so on. All of these factors change
> the height of the displayed page, and hence the amount by which it can be
> scrolled.
That is not a problem, because even in current version, the height of
the whole document is recalculated when we disable images and so on.
However, such events, which cause total recaluclation, will rarely
occur (except the first view of the document).
In current code, (yes Hilary, it begins at DrawRecord,) we have to
render whole paragraph even if we only want the last 1 line to draw.
Rendering speed itself is not slow. I think the functions to render
lines is well tuned and there are not so many rooms to be imploved.
Only the problem is that it renders much outside the screen. Caching
the position of each line, intead of offscreen image, seems easier
for me.
(I might be misunderstanding mechanism of rendering pages....)
/matto
