fixes for "optimized" read reads

git-svn-id: svn://localhost/ardour2/branches/2.0-ongoing@2682 d708f5d6-7413-0410-9779-e7cbd77b26cf

diff --git a/libs/ardour/playlist.cc b/libs/ardour/playlist.cc
index 64efdf77442dd2339bffb6f1c42009bd899ad3f2..e83a29048fadde16c32f30ffb5f99a665ab13e49 100644 (file)
--- a/libs/ardour/playlist.cc
+++ b/libs/ardour/playlist.cc
@@ -1245,88 +1245,73 @@ Playlist::regions_to_read (nframes_t start, nframes_t end)
        /* Caller must hold lock */
 
        RegionList covering;
-       RegionList spanning;
+       set<nframes_t> to_check;
+       set<boost::shared_ptr<Region> > unique;
+       RegionList here;
+
+       to_check.insert (start);
+       to_check.insert (end);
 
        for (RegionList::iterator i = regions.begin(); i != regions.end(); ++i) {
 
                /* find all/any regions that span start+end */
 
                switch ((*i)->coverage (start, end)) {
+               case OverlapNone:
+                       break;
+
                case OverlapInternal:
                        covering.push_back (*i);
-                       spanning.push_back (*i);
                        break;
 
-               case OverlapExternal:
                case OverlapStart:
+                       to_check.insert ((*i)->position());
+                       covering.push_back (*i);
+                       break;
+
                case OverlapEnd:
+                       to_check.insert ((*i)->last_frame());
                        covering.push_back (*i);
-                       
-               case OverlapNone:
+                       break;
+
+               case OverlapExternal:
+                       covering.push_back (*i);
+                       to_check.insert ((*i)->position());
+                       to_check.insert ((*i)->last_frame());
                        break;
                }
 
-               if ((*i)->position() > start) {
+               /* don't go too far */
+
+               if ((*i)->position() > end) {
                        break;
                }
        }
 
        RegionList* rlist = new RegionList;
 
-       if (spanning.size() > 1) {
-               
-               /* find the uppermost/non-transparent regions that span */
-               
-               RegionSortByLayer cmp;
-               spanning.sort (cmp);
-               
-               for (RegionList::reverse_iterator c = spanning.rbegin(); c != spanning.rend(); ++c) {
+       /* find all the regions that cover each position .... */
 
-                       rlist->push_back (*c);
-                       
-                       if ((*c)->opaque()) {
-                               
-                               /* the other regions at this position are hidden by this one */
+       if (covering.size() == 1) {
 
-                               break;
-                       }
-               }
-               
-       } else if (spanning.size() == 1) {
+               rlist->push_back (covering.front());
                
-               rlist->push_back (spanning.front());
-
-       } else if (covering.size() > 1) {
-
-               set<nframes_t> to_check;
-               set<boost::shared_ptr<Region> > unique;
-               RegionList here;
-
-               /* get all starts and ends regions within the range we're looking at */
-
-               to_check.insert (start);
-               to_check.insert (end);
-
-               for (RegionList::iterator x = covering.begin(); x != covering.end(); ++x) {
-                       to_check.insert ((*x)->position());
-                       to_check.insert ((*x)->last_frame());
-               }
-
-               /* find all the regions that cover each position .... */
-
+       } else {
+       
                for (set<nframes_t>::iterator t = to_check.begin(); t != to_check.end(); ++t) {
                        
                        here.clear ();
-
+                       
                        for (RegionList::iterator x = covering.begin(); x != covering.end(); ++x) {
+                       
                                if ((*x)->covers (*t)) {
                                        here.push_back (*x);
                                }
                        }
-
+                       
                        RegionSortByLayer cmp;
                        here.sort (cmp);
-
+                       
                        /* ... and get the top/transparent regions at "here" */
                        
                        for (RegionList::reverse_iterator c = here.rbegin(); c != here.rend(); ++c) {
@@ -1336,27 +1321,22 @@ Playlist::regions_to_read (nframes_t start, nframes_t end)
                                if ((*c)->opaque()) {
                                        
                                        /* the other regions at this position are hidden by this one */
-
+                                       
                                        break;
                                }
                        }
                }
-
+               
                for (set<boost::shared_ptr<Region> >::iterator s = unique.begin(); s != unique.end(); ++s) {
                        rlist->push_back (*s);
                }
 
-       } else if (covering.size() == 1) {
-
-               rlist->push_back (covering.front());
-               
-       }
-
-       if (rlist->size() > 1) {
-               /* now sort by time order */
-               
-               RegionSortByPosition cmp;
-               rlist->sort (cmp);
+               if (rlist->size() > 1) {
+                       /* now sort by time order */
+                       
+                       RegionSortByPosition cmp;
+                       rlist->sort (cmp);
+               }
        }
 
        return rlist;