loader/dri3: import prime buffers in the currently-bound screen

This tries to mirrors the codepath taken by DRI2 in IntelSetTexBuffer2()
and fixes many applications when using DRI3:
 - Totem with libva on hw-accelerated decoding
 - obs-studio, using Window Capture (Xcomposite) as a Source
 - gstreamer with VAAPI

v2:
 - introduce get_dri_screen() in the dri3 loader's vtable (krh)

Tested-by: Timo Aaltonen <[email protected]>
Tested-by: Ionut Biru <[email protected]>
Cc: [email protected]
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=71759
Reviewed-by: Emil Velikov <[email protected]>
Signed-off-by: Martin Peres <[email protected]>
(cherry picked from commit a599b1c2037ac8aca6c92350c8a7b3e42c81deaa)

1 files changed, 11 insertions, 1 deletions

diff --git a/src/loader/loader_dri3_helper.c b/src/loader/loader_dri3_helper.c
index 2411c0acf6c..4c2e849be73 100644
--- a/src/loader/loader_dri3_helper.c
+++ b/src/loader/loader_dri3_helper.c
@@ -1111,6 +1111,7 @@ dri3_get_pixmap_buffer(__DRIdrawable *driDrawable, unsigned int format,
    xcb_sync_fence_t                     sync_fence;
    struct xshmfence                     *shm_fence;
    int                                  fence_fd;
+   __DRIscreen                          *cur_screen;
 
    if (buffer)
       return buffer;
@@ -1141,8 +1142,17 @@ dri3_get_pixmap_buffer(__DRIdrawable *driDrawable, unsigned int format,
    if (!bp_reply)
       goto no_image;
 
+   /* Get the currently-bound screen or revert to using the drawable's screen if
+    * no contexts are currently bound. The latter case is at least necessary for
+    * obs-studio, when using Window Capture (Xcomposite) as a Source.
+    */
+   cur_screen = draw->vtable->get_dri_screen(draw);
+   if (!cur_screen) {
+       cur_screen = draw->dri_screen;
+   }
+
    buffer->image = loader_dri3_create_image(draw->conn, bp_reply, format,
-                                            draw->dri_screen, draw->ext->image,
+                                            cur_screen, draw->ext->image,
                                             buffer);
    if (!buffer->image)
       goto no_image;