Envelopes: gain inlet reads 1 when nothing is connected

docs/releases/max-v0.3.0.md

@@ -28,6 +28,8 @@ First release of Zerr* for Max, as a package for Max 9 on Apple Silicon (arm64,
 
 ## Fixes
 
+- `zerr.envelopes~`: the gain inlet reads 1 when nothing is connected to it. It used to read
+  0, so a plain object with only a control signal was silent.
 - `zerr.envelopes~` and `zerr.features~` no longer overflow when the signal vector size grows
   after creation or inside a resampled `poly~`; they adopt the chain's rate and vector size.
   Neither can throw into Max's audio thread any more. (#28, #29)

docs/releases/pd-next.md

@@ -3,6 +3,12 @@ Renamed to `pd-v<ver>.md` when the version in `puredata/zerr-meta.pd` is decided
 since 2026-10-15 only; everything earlier since `v0.2` still has to be enumerated with
 `git log v0.2..HEAD --oneline -- core puredata` before the first `pd-v` tag._
 
+## Changed
+
+- `zerr_envelopes~`: the gain inlet (third) reads 1 when nothing is connected to it; a float
+  sent there sets a constant gain, as for any Pd signal inlet. It used to read 0, so a plain
+  object with only a control signal was silent.
+
 ## Fixed
 
 - The externals no longer trust the block size they were created with. A `[block~]` subpatch of

maxmsp/README.md

@@ -104,7 +104,7 @@ Inlets (all signals):
 
 1. control signal: 0 to 1 position (trajectory) or pulses (trigger)
 2. spread, 0 to 1 (trigger mode only)
-3. gain, applied to every envelope
+3. gain, applied to every envelope (1 when nothing is connected)
 
 Outlet: multichannel signal, one channel per speaker, in the layout's numbering.
 

maxmsp/source/projects/zerr.envelopes_tilde/zerr.envelopes_tilde.cpp

@@ -256,7 +256,7 @@ void zerr_envelopes_assist(t_zerr_envelopes* x, void* b, long m, long a, char* s
                       "mode)");
             break;
         case 2:
-            strcpy(s, "(signal) gain applied to every envelope");
+            strcpy(s, "(signal) gain applied to every envelope; 1 when nothing is connected");
             break;
         default:
             strcpy(s, "(signal)");
@@ -295,6 +295,9 @@ void zerr_envelopes_dsp64(t_zerr_envelopes* x, t_object* dsp64, short* count, do
                      maxvectorsize, samplerate);
     }
 
+    // count[] says which signal inlets have a cord; the gain inlet is unity without one
+    x->ze->setGainConnected(count != NULL && count[2] != 0);
+
     dsp_add64(dsp64, (t_object*)x, (t_perfroutine64)zerr_envelopes_perform64, 0, NULL);
 }
 

maxmsp/source/projects/zerr.envelopes_tilde/zerr_envelopes.hpp

@@ -156,6 +156,12 @@ class ZerrEnvelopes {
         const long count = std::min<long>(sampleframes, block);
 
         for (int i = 0; i < inputCount; ++i) {
+            if (i == gainInlet && !gainConnected.load(std::memory_order_relaxed)) {
+                // Nothing on the gain inlet: Max hands over zeros, which would mute every
+                // envelope. Unity gain instead, so a plain object plays.
+                std::fill(inputBuffer[i].begin(), inputBuffer[i].end(), 1.0);
+                continue;
+            }
             if (!ins[i]) {
                 silence(outs, numouts, sampleframes);
                 return;
@@ -236,6 +242,17 @@ class ZerrEnvelopes {
     /** @brief Posts the speaker setup to the Console */
     void printParameters() { generator->printParameters(); }
 
+    /**
+     * @brief Whether a patch cord is on the gain inlet, from dsp64's count[]
+     *
+     * Unconnected, the inlet counts as unity gain. Main thread, at DSP setup; the running
+     * perform() picks it up on its next block.
+     */
+    void setGainConnected(bool connected)
+    {
+        gainConnected.store(connected, std::memory_order_relaxed);
+    }
+
   private:
     /**
      * @brief Zeroes every output buffer; the fallback whenever processing cannot proceed
@@ -252,8 +269,10 @@ class ZerrEnvelopes {
         }
     }
 
-    static constexpr int inputCount = 3; /**< Signal inlets: control(0), spread(1), gain(2) */
-    int outputCount                 = 0; /**< One envelope per speaker in the layout */
+    static constexpr int inputCount = 3;    /**< Signal inlets: control(0), spread(1), gain(2) */
+    static constexpr int gainInlet  = 2;    /**< The inlet that reads 1 when nothing is connected */
+    std::atomic<bool> gainConnected{false}; /**< A cord is on the gain inlet (dsp64 count[]) */
+    int outputCount = 0;                    /**< One envelope per speaker in the layout */
 
     zerr::SystemConfigs systemConfigs; /**< Shape the generator is currently sized for */
     std::string selectionMode;         /**< "trajectory" or "trigger" */

puredata/src/zerr_envelopes~.cpp

@@ -103,7 +103,8 @@ void* zerr_envelopes_tilde_new(__attribute__((unused)) t_symbol* s, int argc, t_
 
     // create inlets
     x->spread_inlet = inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
-    x->volume_inlet = inlet_new(&x->x_obj, &x->x_obj.ob_pd, &s_signal, &s_signal);
+    // gain: 1 when nothing is connected (a float sent here sets a constant, as usual)
+    x->volume_inlet = signalinlet_new(&x->x_obj, 1.0f);
 
     // create outlets
     x->n_outlet = x->z->numOutlet; // get the number of outlets