[vlc-devel] [PATCH 03/23] video context: add a function to test if 2 context are similar

[Steve Lhomme]

If they are not similar a converter from one to the other should be used.

A NULL callback is allowed, in which case only the type of the video context
is checked.
---
 include/vlc_picture.h            | 11 +++++++++++
 modules/hw/vdpau/avcodec.c       |  2 +-
 modules/video_chroma/d3d11_fmt.c |  2 +-
 modules/video_chroma/d3d9_fmt.c  |  2 +-
 src/input/decoder_helpers.c      | 16 ++++++++++++++++
 src/libvlccore.sym               |  1 +
 6 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/include/vlc_picture.h b/include/vlc_picture.h
index a5931ef67af..c9bf28a9ed8 100644
--- a/include/vlc_picture.h
+++ b/include/vlc_picture.h
@@ -85,6 +85,11 @@ typedef struct vlc_video_context vlc_video_context;
 struct vlc_video_context_operations
 {
     void (*destroy)(void *priv);
+    /**
+     * Check if two video context of the same type are similar.
+     * The callback can be NULL.
+     */
+    bool (*similar)(const vlc_video_context*, const vlc_video_context*);
 };
 
 /** Decoder device type */
@@ -110,6 +115,12 @@ VLC_API void vlc_video_context_Release(vlc_video_context *);
 VLC_API enum vlc_video_context_type vlc_video_context_GetType(const vlc_video_context *);
 VLC_API void *vlc_video_context_GetPrivate(vlc_video_context *, enum vlc_video_context_type);
 VLC_API vlc_video_context *vlc_video_context_Hold(vlc_video_context *);
+/**
+ * Test if two video context are similar/compatible.
+ *
+ * Video Context are similar when they can use surfaces from one another.
+ */
+VLC_API bool vlc_video_context_IsSimilar(const vlc_video_context *, const vlc_video_context *);
 
 /**
  * Get the decoder device used by the device context.
diff --git a/modules/hw/vdpau/avcodec.c b/modules/hw/vdpau/avcodec.c
index 74aa135f70c..6f9a75fd803 100644
--- a/modules/hw/vdpau/avcodec.c
+++ b/modules/hw/vdpau/avcodec.c
@@ -153,7 +153,7 @@ static void DestroyVDPAUVideoContext(void *private)
 }
 
 const struct vlc_video_context_operations vdpau_vctx_ops = {
-    DestroyVDPAUVideoContext,
+    DestroyVDPAUVideoContext, NULL // TODO
 };
 
 static int Open(vlc_va_t *va, AVCodecContext *avctx, const AVPixFmtDescriptor *desc,
diff --git a/modules/video_chroma/d3d11_fmt.c b/modules/video_chroma/d3d11_fmt.c
index 77156f509bb..edb39244a33 100644
--- a/modules/video_chroma/d3d11_fmt.c
+++ b/modules/video_chroma/d3d11_fmt.c
@@ -771,7 +771,7 @@ static void ReleaseD3D11ContextPrivate(void *private)
 }
 
 const struct vlc_video_context_operations d3d11_vctx_ops = {
-    ReleaseD3D11ContextPrivate,
+    ReleaseD3D11ContextPrivate, NULL // TODO
 };
 
 void d3d11_pic_context_destroy(picture_context_t *ctx)
diff --git a/modules/video_chroma/d3d9_fmt.c b/modules/video_chroma/d3d9_fmt.c
index 508bfc838f8..3a53484908e 100644
--- a/modules/video_chroma/d3d9_fmt.c
+++ b/modules/video_chroma/d3d9_fmt.c
@@ -293,7 +293,7 @@ static void ReleaseD3D9ContextPrivate(void *private)
 }
 
 const struct vlc_video_context_operations d3d9_vctx_ops = {
-    ReleaseD3D9ContextPrivate,
+    ReleaseD3D9ContextPrivate, NULL // TODO
 };
 
 void d3d9_pic_context_destroy(picture_context_t *ctx)
diff --git a/src/input/decoder_helpers.c b/src/input/decoder_helpers.c
index 3ff71f49c23..e4b8f2797b6 100644
--- a/src/input/decoder_helpers.c
+++ b/src/input/decoder_helpers.c
@@ -294,3 +294,19 @@ vlc_decoder_device* vlc_video_context_HoldDevice(vlc_video_context *vctx)
         return NULL;
     return vlc_decoder_device_Hold( vctx->device );
 }
+
+bool vlc_video_context_IsSimilar(const vlc_video_context *a, const vlc_video_context *b)
+{
+    if (!a && !b)
+        return true;
+    if (!a || !b)
+        return false;
+    if (a->private_type != b->private_type)
+        return false;
+    if (a->ops == NULL)
+    {
+        assert(b->ops == NULL);
+        return b->ops == NULL;
+    }
+    return a->ops->similar == NULL || a->ops->similar(a, b);
+}
diff --git a/src/libvlccore.sym b/src/libvlccore.sym
index 7dce1c2c25b..3ea59614722 100644
--- a/src/libvlccore.sym
+++ b/src/libvlccore.sym
@@ -952,3 +952,4 @@ vlc_video_context_GetType
 vlc_video_context_GetPrivate
 vlc_video_context_Hold
 vlc_video_context_HoldDevice
+vlc_video_context_IsSimilar
-- 
2.17.1