[cairo] how to substitute CAIRO_CLIP_PATH_IS_BOX ?

[Chris Wilson]

On Fri, Dec 11, 2015 at 01:07:55PM +0100, Enrico Weigelt, metux IT consult wrote:
> Hi folks,
> 
> 
> the flags field in cairo_clip_path_t had been removed, but the DRM
> backend still uses it:
> 
> > static cairo_clip_path_t *
> > _clip_get_solitary_path (const cairo_clip_t *clip)
> > {
> >     cairo_clip_path_t *iter = clip->path;
> >     cairo_clip_path_t *path = NULL;
> >
> >     do {
> >         if ((iter->flags & CAIRO_CLIP_PATH_IS_BOX) == 0) {
> >             if (path != NULL)
> >                 return FALSE;
> >
> >             path = iter;
> >         }
> >         iter = iter->prev;
> >     } while (iter != NULL);
> >
> >     return path;
> > }
> 
> 
> How should I substitute it ?

This basically was replace by cairo_clip_t managing boxes explicitly.
However, in this case what you want to convert over to is
_cairo_clip_get_polygon(). The intention is that we can reduce complex
clips very often to a single polygon and that even do geometric
intersection of clip paths with shapes (to avoid the fill overhead of
rendering multiple passes).
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre