[vlc-devel] [PATCH] picture: always copy context when cloning

[Alexandre Janniaux]

picture_Clone was copying the original picture context into the new
clone while picture_pool_Clone wasn't. As it is possible to create a
pool from existing pictures, it's quite handy to be able to associate
the graphical resources needed for each picture to their context so
that it can be retrieved after a call to picture_pool_Wait/Get.

The rationale is that because resources like pixels are shared between
the original picture and the clone, we should probably do the same with
picture_context and have a unified way for picture producer to
reference such resources.

This patch remove the special handling in picture_Clone and move it to
picture_InternalClone for that reason.
---
 src/misc/picture.c      | 11 +++++++----
 src/misc/picture_pool.c |  6 ++++--
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/src/misc/picture.c b/src/misc/picture.c
index e00b1303253..047d4d22477 100644
--- a/src/misc/picture.c
+++ b/src/misc/picture.c
@@ -440,18 +440,21 @@ picture_t *picture_InternalClone(picture_t *picture,
     picture_t *clone = picture_NewFromResource(&picture->format, &res);
     if (likely(clone != NULL)) {
         ((picture_priv_t *)clone)->gc.opaque = opaque;
+
+        /* The picture context is responsible for potentially holding the
+         * video context attached to the picture if needed. */
+        if (picture->context != NULL)
+            clone->context = picture->context->copy(picture->context);
+
         picture_Hold(picture);
     }
+
     return clone;
 }
 
 picture_t *picture_Clone(picture_t *picture)
 {
     picture_t *clone = picture_InternalClone(picture, picture_DestroyClone, picture);
-    if (likely(clone != NULL)) {
-        if (picture->context != NULL)
-            clone->context = picture->context->copy(picture->context);
-    }
     return clone;
 }
 
diff --git a/src/misc/picture_pool.c b/src/misc/picture_pool.c
index 5f0f41eba8e..1b979d5a23a 100644
--- a/src/misc/picture_pool.c
+++ b/src/misc/picture_pool.c
@@ -90,8 +90,10 @@ static picture_t *picture_pool_ClonePicture(picture_pool_t *pool,
     picture_t *picture = pool->picture[offset];
     uintptr_t sys = ((uintptr_t)pool) + offset;
 
-    return picture_InternalClone(picture, picture_pool_ReleasePicture,
-                                 (void*)sys);
+    picture_t *clone = picture_InternalClone(picture,
+                                             picture_pool_ReleasePicture,
+                                             (void*)sys);
+    return clone;
 }
 
 picture_pool_t *picture_pool_New(unsigned count, picture_t *const *tab)
-- 
2.27.0