[gimp-gap/gap-2-8] fix storyboard audio rendering bug

[Wolfgang Hofer <wolfgangh src gnome org>]

commit 6206b2ff4b3af5087815a4c1c6eeb0fb192e2ebe
Author: Wolfgang Hofer <wolfgangh svn gnome org>
Date:   Sun Oct 8 09:35:59 2017 +0200

    fix storyboard audio rendering bug

 ChangeLog                    |   12 ++++++++++++
 gap/gap_story_render_audio.c |   22 ++++++++++++++--------
 gap/gap_story_render_types.h |    1 +
 3 files changed, 27 insertions(+), 8 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 0486d5a..1fc4486 100755
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,15 @@
+2017-10-08 Wolfgang Hofer <hof gimp org>
+
+- Fix for Storyboard Audio rendering in case where clips of the same 
+  video (AUD_PLAY_MOVIE Storyboardelemnts) are used in more than 
+  one audio track of the Storyboard.
+  The bug triggered a huge amount of alternating audio segemnt load operations
+  in the composite audiofile audiomix processing. This caused extreme slow rendering
+  where one minute of audio did not finish in hours.
+
+ * gap/gap_story_render_types.h
+ * gap/gap_story_render_audio.c
+
 2017-04-15 Wolfgang Hofer <hof gimp org>
 
 - MovePath support Handle Offsets, "Reset all controlpoints" Button protects keyframe information by default
diff --git a/gap/gap_story_render_audio.c b/gap/gap_story_render_audio.c
index 6883c8a..a45e845 100644
--- a/gap/gap_story_render_audio.c
+++ b/gap/gap_story_render_audio.c
@@ -108,7 +108,7 @@ static GapStoryRenderAudioCache *global_audcache = NULL;
 
 
 static void     p_drop_audio_cache_elem1(GapStoryRenderAudioCache *audcache);
-static GapStoryRenderAudioCacheElem  *p_load_cache_audio( char* filename, gint32 *audio_id, gint32 
*aud_bytelength, gint32 seek_idx);
+static GapStoryRenderAudioCacheElem  *p_load_cache_audio(gint32 audio_track, char* filename, gint32 
*audio_id, gint32 *aud_bytelength, gint32 seek_idx);
 static void     p_find_min_max_aud_tracknumbers(GapStoryRenderAudioRangeElem *aud_list
                               , gint32 *lowest_tracknr
                               , gint32 *highest_tracknr);
@@ -243,7 +243,7 @@ gap_story_render_remove_tmp_audiofiles(GapStoryRenderVidHandle *vidhand)
  * ----------------------------------------------------
  */
 static GapStoryRenderAudioCacheElem  *
-p_load_cache_audio( char* filename, gint32 *audio_id, gint32 *aud_bytelength, gint32 seek_idx)
+p_load_cache_audio(gint32 audio_track, char* filename, gint32 *audio_id, gint32 *aud_bytelength, gint32 
seek_idx)
 {
   gint32 l_idx;
   gint32 l_audio_id;
@@ -277,13 +277,16 @@ p_load_cache_audio( char* filename, gint32 *audio_id, gint32 *aud_bytelength, gi
   for(ac_ptr = audcache->ac_list; ac_ptr != NULL; ac_ptr = (GapStoryRenderAudioCacheElem *)ac_ptr->next)
   {
     l_idx++;
-    if(strcmp(filename, ac_ptr->filename) == 0)
+    if (audio_track == ac_ptr->owner_track)
     {
-      /* audio found in cache, can skip load */
-      *audio_id       = ac_ptr->audio_id;
-      *aud_bytelength = ac_ptr->aud_bytelength;
+      if(strcmp(filename, ac_ptr->filename) == 0)
+      {
+        /* audio found in cache, can skip load */
+        *audio_id       = ac_ptr->audio_id;
+        *aud_bytelength = ac_ptr->aud_bytelength;
 
-      return(ac_ptr);
+        return(ac_ptr);
+      }
     }
     ac_last = ac_ptr;
   }
@@ -300,6 +303,8 @@ p_load_cache_audio( char* filename, gint32 *audio_id, gint32 *aud_bytelength, gi
     *audio_id = l_audio_id;
     ac_new = g_malloc0(sizeof(GapStoryRenderAudioCacheElem));
     ac_new->filename = g_strdup(filename);
+    
+    ac_new->owner_track = audio_track;
     ac_new->audio_id = l_audio_id;
     ac_new->aud_data = aud_data;
     ac_new->aud_bytelength = *aud_bytelength;
@@ -450,7 +455,8 @@ p_get_audio_sample(GapStoryRenderVidHandle *vidhand        /* IN  */
            }
 
            if(gap_debug) printf("BEFORE p_load_cache_audio  %s\n", l_audiofile);
-           ac_elem = p_load_cache_audio(l_audiofile
+           ac_elem = p_load_cache_audio(aud_elem->track
+                                       , l_audiofile
                                        , &aud_elem->audio_id
                                        , &aud_elem->aud_bytelength
                                        , l_seek_idx
diff --git a/gap/gap_story_render_types.h b/gap/gap_story_render_types.h
index 850208c..c2535b4 100644
--- a/gap/gap_story_render_types.h
+++ b/gap/gap_story_render_types.h
@@ -101,6 +101,7 @@ typedef struct GapStoryRenderImageCache
 
 typedef struct GapStoryRenderAudioCacheElem
 {
+   gint32  owner_track; /* owner audio track (other tracks have their own cache to avoid frequent segment 
reloads) */ 
    gint32  audio_id;
    char   *filename;
    guchar *aud_data;   /* full audiodata (including header) loaded in memory */