RenderLayer code

[Lars Knoll]

> On Friday, January 31, 2003, at 01:30 AM, Lars Knoll wrote:
> >> On Friday, January 31, 2003, at 01:07 AM, Lars Knoll wrote:
> >>> I still don't pass test 4 however (see attached screenshot). I think
> >>> your code
> >>> flattening the ztree does not honour document order when zindeces are
> >>> equal.
> >>
> >> I pass this test.  Something else must be missing...
> >
> > As I said, the tree you build has no information about document order.
> > I could
> > imagine something going wrong in the sorting, but I'll check.
>
> In the newest diff I gave you, the layers preserve document order (in
> their layer tree).  There were bugs with that where I was always just
> appending layers to the end of their child lists.  Now you can even
> dynamically position elements and new layers will appear and be
> inserted into the correct place in the document.

Ok. I'll try to integrate it after I come back from skiing (ie on Wednesday).

> >>> I thought about adding a RenderLayer *nextToPaint pointer to the
> >>> layers
> >>> themselves. Like that one would not need an extra list. If a layer
> >>> gets
> >>> inserted or removed, the paint order can be recalculated, but the
> >>> paint()
> >>> method should not need to do this.
> >>
> >> Note that the ztree construction prunes out layers that don't
> >> intersect
> >> your dirty rect, so the list can be different depending on the dirty
> >> rect.
> >
> > We don't do that any other place in the rendering tree. You usually
> > have a
> > handful of layers, so I don't see why we can't calculate the complete
> > order
> > over the whole document and do the clipping out when painting, similar
> > to how
> > we do it in all the paint methods of the different render objects.
> >
> > IMO it has to be faster, since you have to iterate over all RenderLayer
> > objects with every paint() call anyways (now to create the tree, then
> > to
> > check if they have to be painted).
>
> Yeah, I think you're right.  Let me play around with the code a bit.
> I'll look into making that change and send you a new render_layer.cpp
> file.

Cool. Thanks a lot.

Lars