[PATCH v2 4/5] wined3d: Use context->ops->prepare_upload_bo() in wined3d_device_context_map() if possible.

[Henri Verbeet]

On Wed, 30 Jun 2021 at 18:45, Zebediah Figura (she/her)
<zfigura at codeweavers.com> wrote:
> On 6/30/21 7:14 AM, Henri Verbeet wrote:
> > Would we ever use ops->get_upload_bo() and ops->unmap() independently
> > of each other? If not, we may as well merge those together.
> >
>
> No, but they're conceptually pretty different, and merging them strikes
> me as ugly...
>
Well, wined3d_device_context_unmap() seems conceptually similar enough
to wined3d_deferred_context_unmap(). I.e., we could implement
wined3d_deferred_context_unmap() like this:

    ...
    if (!wined3d_deferred_context_get_upload_bo(...))
        return E_NOTIMPL;

    wined3d_resource_get_sub_resource_map_pitch(...);
    wined3d_device_context_upload_bo(...);

    return WINED3D_OK;

which doesn't seem terrible, and then just call ops->unmap() in
wined3d_device_context_unmap() like we do now. Of course,
wined3d_cs_unmap() would be different, but it would also retrieve the
upload bo in a different way.

Alternatively, we could do something like this in
wined3d_device_context_unmap():

    ...
    if (context->ops->get_upload_bo(...))
    {
        ...
        wined3d_device_context_upload_bo(...);
        return WINED3D_OK;
    }
    ...
    return wined3d_device_context_emit_unmap(...);

which should also work, and may be preferable, because we could
implement wined3d_device_context_map() and
wined3d_device_context_update_sub_resource() in a similar way. I.e., I
think we can make this work with either
prepare_upload_bo()/get_upload_bo() or
update_sub_resource()/map()/unmap() in the device context ops, but we
probably don't need both sets of ops.