MIDI: Make seeking neater by moving it into another file. Will be more useful later.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@15467 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 63 insertions, 8 deletions

diff --git a/apps/plugins/midi/sequencer.c b/apps/plugins/midi/sequencer.c
index b9cc83f..4e6c15f 100644
--- a/apps/plugins/midi/sequencer.c
+++ b/apps/plugins/midi/sequencer.c
@@ -142,7 +142,6 @@ const uint32_t pitchTbl[] ICONST_ATTR={
 
 static void findDelta(struct SynthObject * so, int ch, int note)
 {
-
     struct GWaveform * wf = patchSet[chPat[ch]]->waveforms[patchSet[chPat[ch]]->noteTable[note]];
     so->wf=wf;
     unsigned int delta= 0;
@@ -152,14 +151,8 @@ static void findDelta(struct SynthObject * so, int ch, int note)
     so->delta = delta;
 }
 
-static inline void setPW(int ch, int msb, int lsb)
+static inline void computeDeltas(int ch)
 {
-    chPW[ch] = msb<<2|lsb>>5;
-
-    int totalBend = (chPW[ch]-256) * chPBDepth[ch];
-    chPBNoteOffset[ch] = totalBend >> 8;
-    chPBFractBend[ch] = pitchTbl[(totalBend & 0xFF) + 256];
-
     int a=0;
     for(a = 0; a<MAX_VOICES; a++)
     {
@@ -170,6 +163,17 @@ static inline void setPW(int ch, int msb, int lsb)
     }
 }
 
+static inline void setPW(int ch, int msb, int lsb)
+{
+    chPW[ch] = msb<<2|lsb>>5;
+
+    int totalBend = (chPW[ch]-256) * chPBDepth[ch];
+    chPBNoteOffset[ch] = totalBend >> 8;
+    chPBFractBend[ch] = pitchTbl[(totalBend & 0xFF) + 256];
+
+    computeDeltas(ch);
+}
+
 inline void pressNote(int ch, int note, int vol)
 {
     static int lastKill = 0;
@@ -376,7 +380,58 @@ void rewindFile(void)
     }
 }
 
+
 int tick(void) ICODE_ATTR;
+
+void seekBackward(int nsec)
+{
+    int notesUsed = 0, a=0;
+    int desiredTime = playingTime - nsec;  /* Rewind 5 sec */
+
+    if(desiredTime < 0)
+        desiredTime = 0;
+
+    /* Set controllers to default values */
+    resetControllers();
+
+    /* Set the tempo to defalt */
+    bpm=mf->div*1000000/tempo;
+    numberOfSamples=SAMPLE_RATE/bpm;
+
+
+    /* Reset the tracks to start */
+    rewindFile();
+
+    /* Reset the time counter to 0 */
+    playingTime = 0;
+    samplesThisSecond = 0;
+
+    /* Quickly run through any initial things that occur before notes */
+    do
+    {
+        notesUsed = 0;
+        for(a=0; a<MAX_VOICES; a++)
+            if(voices[a].isUsed == 1)
+                notesUsed++;
+        tick();
+    } while(notesUsed == 0);
+
+    /* Reset the time counter to 0 */
+    playingTime = 0;
+    samplesThisSecond = 0;
+
+    /* Tick until goal is reached */
+    while(playingTime < desiredTime)
+        tick();
+}
+
+
+void seekForward(int nsec)
+{
+    int desiredTime = playingTime + nsec;
+    while(tick() && playingTime < desiredTime);
+}
+
 int tick(void)
 {
     if(mf==NULL)