Merge pull request #129 from shorepine/pcmloop

src/amy.c

@@ -488,7 +488,7 @@ void amy_add_event_internal(struct event e, uint16_t base_osc) {
             for(uint8_t j=0;j<MAX_BREAKPOINTS;j++) {
                 d.param=BP_START+(j*2)+(i*MAX_BREAKPOINTS*2); d.data = *(uint32_t *)&t.breakpoint_times[i][j]; add_delta_to_queue(d);
                 // Stop adding deltas after first UNSET time sent, just to mark the end of the set when overwriting.
-                if(!AMY_IS_SET(t.breakpoint_times[i][j])) break;
+                if(AMY_IS_UNSET(t.breakpoint_times[i][j])) break;
                 d.param=BP_START+(j*2 + 1)+(i*MAX_BREAKPOINTS*2); d.data = *(uint32_t *)&t.breakpoint_values[i][j]; add_delta_to_queue(d);
             }
         }
@@ -980,26 +980,27 @@ void play_event(struct delta d) {
                 #if AMY_KS_OSCS > 0
                 ks_note_off(d.osc);
                 #endif
-            }
-            else if(synth[d.osc].wave==ALGO) { algo_note_off(d.osc); }
-            else if(synth[d.osc].wave==PARTIAL) {
+            } else if(synth[d.osc].wave==ALGO) {
+                algo_note_off(d.osc);
+            } else if(synth[d.osc].wave==PARTIAL) {
                 #if AMY_HAS_PARTIALS == 1
                 partial_note_off(d.osc);
                 #endif
-            }
-            else if(synth[d.osc].wave==PARTIALS) {
+            } else if(synth[d.osc].wave==PARTIALS) {
                 #if AMY_HAS_PARTIALS == 1
                 partials_note_off(d.osc);
                 #endif
-            }
-            else if(synth[d.osc].wave==PCM) { pcm_note_off(d.osc); }
-            else if(synth[d.osc].wave==CUSTOM) {
+            } else if(synth[d.osc].wave==PCM) {
+                pcm_note_off(d.osc);
+            } else if(synth[d.osc].wave==CUSTOM) {
                 #if AMY_HAS_CUSTOM == 1
                 custom_note_off(d.osc);
                 #endif
-            }
-            else {
+            } else {
                 // osc note off, start release
+                // For now, note_off_clock signals note of BUT ONLY IF IT'S NOT KS, ALGO, PARTIAL, PARTIALS, PCM, or CUSTOM.
+                // I'm not crazy about this, but if we apply it in those cases, the default bp0 amp envelope immediately zeros-out
+                // those waves on note-off.
                 AMY_UNSET(synth[d.osc].note_on_clock);
                 synth[d.osc].note_off_clock = total_samples;
             }
@@ -1073,7 +1074,9 @@ void hold_and_modify(uint16_t osc) {
     msynth[osc].amp = combine_controls_mult(ctrl_inputs, synth[osc].amp_coefs);
     if (msynth[osc].amp <= 0.001)  msynth[osc].amp = 0;
 
-    msynth[osc].feedback = synth[osc].feedback;
+    // synth[osc].feedback is copied to msynth in pcm_note_on, then used to track note-off for looping PCM.
+    // For PCM, don't re-copy it every loop, or we'd lose track of that flag.  (This means you can't change feedback mid-playback for PCM).
+    if (synth[osc].wave != PCM)  msynth[osc].feedback = synth[osc].feedback;
     msynth[osc].resonance = synth[osc].resonance;
 
     if (osc == 999) {

src/pcm.c

@@ -24,20 +24,23 @@ void pcm_note_on(uint16_t osc) {
         // This will result in PCM_SAMPLE_RATE when the midi_note == patch->midinote.
         synth[osc].logfreq_coefs[COEF_CONST] = PCM_AMY_LOG2_SAMPLE_RATE - logfreq_for_midi_note(pcm_map[synth[osc].patch].midinote);
     }
-    synth[osc].phase = 0; // s16.15 index into the table; as if a PHASOR into a 16 bit sample table. 
+    synth[osc].phase = 0; // s16.15 index into the table; as if a PHASOR into a 16 bit sample table.
+    // Special case: We use the msynth feedback flag to indicate note-off for looping PCM.  As a result, it's explicitly NOT set in amy:hold_and_modify for PCM voices.  Set it here.
+    msynth[osc].feedback = synth[osc].feedback;
 }
 
 void pcm_mod_trigger(uint16_t osc) {
     pcm_note_on(osc);
 }
 
 void pcm_note_off(uint16_t osc) {
-    // if looping set, disable looping; sample should play through to end.
-    if(msynth[osc].feedback > 0) {
-        msynth[osc].feedback = 0;
-    } else {
-        // Set phase to the end to cause immediate stop.
+    if(msynth[osc].feedback == 0) {
+        // Non-looping note: Set phase to the end to cause immediate stop.
         synth[osc].phase = F2P(pcm_map[synth[osc].patch].length / (float)(1 << PCM_INDEX_FRAC_BITS));
+    } else {
+        // Looping is requested, disable future looping, sample will play through to end.
+        // (sending a second note-off will stop it immediately).
+        msynth[osc].feedback = 0;
     }
 }
 
@@ -47,14 +50,15 @@ SAMPLE render_pcm(SAMPLE* buf, uint16_t osc) {
     const pcm_map_t* patch = &pcm_map[synth[osc].patch];
     float logfreq = msynth[osc].logfreq;
     // If osc[midi_note] is unset, apply patch's default here.
-    if (!AMY_IS_SET(synth[osc].midi_note))  logfreq += logfreq_for_midi_note(patch->midinote);
+    if (AMY_IS_UNSET(synth[osc].midi_note))  logfreq += logfreq_for_midi_note(patch->midinote);
     float playback_freq = freq_of_logfreq(logfreq);  // PCM_SAMPLE_RATE modified by
 
     SAMPLE max_value = 0;
     SAMPLE amp = F2S(msynth[osc].amp);
     PHASOR step = F2P((playback_freq / (float)AMY_SAMPLE_RATE) / (float)(1 << PCM_INDEX_BITS));
     const LUTSAMPLE* table = pcm + patch->offset;
     uint32_t base_index = INT_OF_P(synth[osc].phase, PCM_INDEX_BITS);
+    //fprintf(stderr, "render_pcm: time=%.3f patch=%d base_index=%d length=%d loopstart=%d loopend=%d fb=%f is_unset_note_off %d\n", total_samples / (float)AMY_SAMPLE_RATE, synth[osc].patch, base_index, patch->length, patch->loopstart, patch->loopend, msynth[osc].feedback, AMY_IS_UNSET(synth[osc].note_off_clock));
     for(uint16_t i=0; i < AMY_BLOCK_SIZE; i++) {
         SAMPLE frac = S_FRAC_OF_P(synth[osc].phase, PCM_INDEX_BITS);
         LUTSAMPLE b = table[base_index];
@@ -67,11 +71,11 @@ SAMPLE render_pcm(SAMPLE* buf, uint16_t osc) {
             synth[osc].status = STATUS_OFF;// is this right? 
             sample = 0;
         } else {
-            if(msynth[osc].feedback > 0) { // loop       
+            if(msynth[osc].feedback) { // still looping.  The feedback flag is cleared by pcm_note_off.
                 if(base_index >= patch->loopend) { // loopend
                     // back to loopstart
                     int32_t loop_len = patch->loopend - patch->loopstart;
-                    synth[osc].phase -= F2P(loop_len / (float)(1 << PCM_INDEX_FRAC_BITS));
+                    synth[osc].phase -= F2P(loop_len / (float)(1 << PCM_INDEX_BITS));
                     base_index -= loop_len;
                 }
             }

test.py

@@ -124,6 +124,14 @@ def run(self):
     amy.send(time=500, note=70, vel=1)
 
 
+class TestPcmLoop(AmyTest):
+
+  def run(self):
+    amy.send(time=0, osc=0, wave=amy.PCM, patch=10, feedback=1)
+    amy.send(time=100, osc=0, vel=1)
+    amy.send(time=500, osc=0, vel=0)
+
+
 class TestPartial(AmyTest):
 
   def run(self):
@@ -427,7 +435,7 @@ class TestFilterReleaseGlitch(AmyTest):
 
   def run(self):
     amy.send(time=0, osc=0, wave=amy.SAW_DOWN, filter_type=amy.FILTER_LPF24, filter_freq='100,0,0,6')
-    amy.send(time=100, note=60, vel=1)
+    amy.send(time=100, note=64, vel=1)
     amy.send(time=500, vel=0)
 
 
@@ -451,13 +459,14 @@ def main(argv):
     #TestBrass2().test()
     #TestSineEnv().test()
     #TestSawDownOsc().test()
-    TestGuitar().test()
+    #TestGuitar().test()
     #TestFilter().test()
     #TestAlgo().test()
     #TestBleep().test()
     #TestChainedOsc().test()
     #TestJunoPatch().test()
     #TestJunoTrumpetPatch().test()
+    TestPcmLoop().test()
 
   amy.send(debug=0)
   print("tests done.")