[vlc-devel] [PATCH 3/4] libvlc: add the API needed to set/get the viewpoint in 360° videos

[Steve Lhomme]

---
 include/vlc/libvlc_media_player.h | 28 ++++++++++++++++++++++++++++
 lib/media_player.c                |  3 +++
 lib/video.c                       | 37 +++++++++++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+)

diff --git a/include/vlc/libvlc_media_player.h b/include/vlc/libvlc_media_player.h
index 2718a33..222b25a 100644
--- a/include/vlc/libvlc_media_player.h
+++ b/include/vlc/libvlc_media_player.h
@@ -104,6 +104,16 @@ typedef struct libvlc_audio_output_device_t
 } libvlc_audio_output_device_t;
 
 /**
+ * Viewpoint for video outputs
+ */
+typedef struct libvlc_video_viewpoint_t
+{
+    float f_yaw;   /**< view point yaw in degrees ]-180;180] */
+    float f_pitch; /**< view point pitch in degrees ]-180;180] */
+    float f_roll;  /**< view point roll in degrees ]-180;180] */
+} libvlc_video_viewpoint_t;
+
+/**
  * Marq options definition
  */
 typedef enum libvlc_video_marquee_option_t {
@@ -1127,6 +1137,24 @@ LIBVLC_API char *libvlc_video_get_aspect_ratio( libvlc_media_player_t *p_mi );
 LIBVLC_API void libvlc_video_set_aspect_ratio( libvlc_media_player_t *p_mi, const char *psz_aspect );
 
 /**
+ * Get current video viewpoint.
+ *
+ * \param p_mi the media player
+ * \return the video viewpoint or NULL if unspecified
+ * (the result must be released with free() or libvlc_free()).
+ */
+LIBVLC_API libvlc_video_viewpoint_t *libvlc_video_get_viewpoint( libvlc_media_player_t *p_mi );
+
+/**
+ * Set new video viewpoint information.
+ *
+ * \param p_mi the media player
+ * \param psz_aspect new video viewpoint or NULL to reset to default
+ */
+LIBVLC_API void libvlc_video_set_viewpoint( libvlc_media_player_t *p_mi,
+                                            const libvlc_video_viewpoint_t *p_viewpoint );
+
+/**
  * Get current video subtitle.
  *
  * \param p_mi the media player
diff --git a/lib/media_player.c b/lib/media_player.c
index 69d3523..197c9be 100644
--- a/lib/media_player.c
+++ b/lib/media_player.c
@@ -640,6 +640,9 @@ libvlc_media_player_new( libvlc_instance_t *instance )
     var_Create (mp, "zoom", VLC_VAR_FLOAT | VLC_VAR_DOINHERIT);
     var_Create (mp, "aspect-ratio", VLC_VAR_STRING);
     var_Create (mp, "crop", VLC_VAR_STRING);
+    var_Create (mp, "viewpoint-yaw", VLC_VAR_FLOAT | VLC_VAR_DOINHERIT);
+    var_Create (mp, "viewpoint-pitch", VLC_VAR_FLOAT | VLC_VAR_DOINHERIT);
+    var_Create (mp, "viewpoint-roll", VLC_VAR_FLOAT | VLC_VAR_DOINHERIT);
     var_Create (mp, "deinterlace", VLC_VAR_INTEGER);
     var_Create (mp, "deinterlace-mode", VLC_VAR_STRING);
 
diff --git a/lib/video.c b/lib/video.c
index b2c9b34..bee4e6d 100644
--- a/lib/video.c
+++ b/lib/video.c
@@ -281,6 +281,43 @@ void libvlc_video_set_aspect_ratio( libvlc_media_player_t *p_mi,
     free (pp_vouts);
 }
 
+libvlc_video_viewpoint_t *libvlc_video_get_viewpoint( libvlc_media_player_t *p_mi )
+{
+    libvlc_video_viewpoint_t *p_viewpoint = malloc(sizeof(libvlc_video_viewpoint_t));
+    if (p_viewpoint == NULL)
+        return NULL;
+
+    p_viewpoint->f_yaw   = var_GetFloat( p_mi,"viewpoint-yaw" );
+    p_viewpoint->f_pitch = var_GetFloat( p_mi,"viewpoint-pitch" );
+    p_viewpoint->f_roll  = var_GetFloat( p_mi,"viewpoint-roll" );
+    return p_viewpoint;
+}
+
+void libvlc_video_set_viewpoint( libvlc_media_player_t *p_mi,
+                                 const libvlc_video_viewpoint_t *p_viewpoint )
+{
+    if (p_viewpoint == NULL)
+        return;
+
+    var_SetFloat(p_mi, "viewpoint-yaw", p_viewpoint->f_yaw);
+    var_SetFloat(p_mi, "viewpoint-pitch", p_viewpoint->f_pitch);
+    var_SetFloat(p_mi, "viewpoint-roll", p_viewpoint->f_roll);
+
+    char psz_viewpoint[3 * 13];
+    sprintf( psz_viewpoint, "%.7f:%.7f:%.7f",
+             p_viewpoint->f_yaw, p_viewpoint->f_pitch, p_viewpoint->f_roll );
+    size_t n;
+    vout_thread_t **pp_vouts = GetVouts (p_mi, &n);
+    for (size_t i = 0; i < n; i++)
+    {
+        vout_thread_t *p_vout = pp_vouts[i];
+
+        var_SetString (p_vout, "viewpoint", psz_viewpoint);
+        vlc_object_release (p_vout);
+    }
+    free (pp_vouts);
+}
+
 int libvlc_video_get_spu( libvlc_media_player_t *p_mi )
 {
     input_thread_t *p_input_thread = libvlc_get_input_thread( p_mi );
-- 
2.8.2