Re: ddraw correctness fixes patch

[Tony Lambregts]

Matthew Mastracci wrote:
> Thanks for the review - comments inline.
>
> Christian Costa wrote:
> > > The new locking mechanism is wrong. DDLOCK_xxx are just used for 
> > > optimization.
> > >
> > > The thing to do during the blit should be something like that :
> > >
> > > sdesc.dwSize = sizeof(sdesc);
> > > ddesc.dwSize = sizeof(ddesc);
> > > if (src == NULL)
> > > IDirectDrawSurface7_Lock(iface, &lock_dst, &ddesc, DDLOCK_WRITEONLY, 0);
> > > else if (src == iface) {
> > > RECT lock_union = < rect that just contains lock_dst and lock_src >; 
> > > IDirectDrawSurface7_Lock(iface, &lock_union, &ddesc, 0, 0);
> > > sdesc = ddesc;
> >
> > I think here that sdesc and ddesc surface pointers should be remapped 
> > according to lock_src and lock_dest.
>
> The above logic makes sense - I originally tried to solve it this way, 
> but ended up failing because of the sdesc and ddesc mapping issue.  Any 
> idea how to do this cleanly?

I think what will work is IntersectRect() from windows/rect.c

IntersectRect( LPRECT dest, const RECT *src1, const RECT *src2)

Something like the following perhaps?

RECT lock_union

if IntersectRect(&lockunion, &sdesc, &ddesc)
     IDirectDrawSurface7_Lock(iface, &lock_union, &ddesc, 0, 0);
....

--

Tony Lambregts