Audio: target the step-intensity send at FOOTSTEP sources only (task #50)

The output-filtered broadcast still fed EVERY volume/brightness mixer -- the
always-on ambience pulse's own volume mixer got cranked to step intensity on
every stride ('a stuck button', 3/s, loud).  The send now identifies footstep
sources by authored patch (FootFallInt/Ext: bank2 37-39, bank1 106/107) through
mixer->GetTargetComponent() -> AudioSource -> PatchResource LOD bank/patch
(new accessors: GetTargetComponent, GetBankID/GetPatchID,
AudioResource::PeekAudioLevelOfDetail).

Also: step intensity curve raised (speed/25, floor 0.55 -- a mech stomp is
never subtle; it was firing at ~0.4 gain and masked under 0.9-gain layers,
heard as an unrecognizable 'orchestral hit').

Verified: FootFallInt at 0.78 gain in the live tape; the ambience pulse back
to its brief authored form (absent from 1/s snapshots).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

engine/MUNGA/AUDCMP.h

@@ -236,6 +236,7 @@ public:
 	// broadcasts (the foot-plant intensity send) can target only volume/brightness
 	// mix stages and never Start-outputting stages.
 	AudioControlID GetOutputControlID() const { return outputControlID; }
+	AudioComponent *GetTargetComponent() { return audioComponentSocket.GetCurrent(); }
 
 	//
 	//--------------------------------------------------------------------
@@ -316,6 +317,7 @@ public:
 	// broadcasts (the foot-plant intensity send) can target only volume/brightness
 	// mix stages and never Start-outputting stages.
 	AudioControlID GetOutputControlID() const { return outputControlID; }
+	AudioComponent *GetTargetComponent() { return audioComponentSocket.GetCurrent(); }
 
 	//
 	//--------------------------------------------------------------------

engine/MUNGA/AUDLVL.h

@@ -162,6 +162,11 @@ protected:
 	AudioLevelOfDetail*
 		GetAudioLevelOfDetail();
 
+public:
+	// (task #50) public read of the active LOD -- the game-side footstep
+	// intensity send identifies footstep sources by their patch bank/id.
+	AudioLevelOfDetail* PeekAudioLevelOfDetail() { return GetAudioLevelOfDetail(); }
+
 private:
 	//
 	//-----------------------------------------------------------------------

engine/MUNGA_L4/L4AUDLVL.h

@@ -69,6 +69,11 @@ public:
 		GetVoiceCount()
 			{return PRESET_getNumSamples(bankID,patchID);}
 
+	// (task #50) expose the authored bank/patch so the game-side footstep
+	// intensity send can identify footstep sources precisely.
+	int GetBankID()  const { return (int)bankID; }
+	int GetPatchID() const { return (int)patchID; }
+
 	//
 	//-----------------------------------------------------------------------
 	// BuildFromPage

game/reconstructed/mech2.cpp

@@ -91,6 +91,9 @@
 
 #include <bt.hpp>
 #include <AUDCMP.hpp>		// AudioComponent -- the foot-plant step-intensity broadcast
+#include <AUDSRC.hpp>		// AudioSource -- footstep-source identification
+#include <AUDLVL.hpp>		// AudioResource::GetAudioLevelOfDetail
+#include <L4AUDLVL.hpp>	// PatchLevelOfDetail -- bank/patch of the target source
 #pragma hdrstop
 
 #if !defined(MECH_HPP)
@@ -281,29 +284,53 @@ void
 		// by their own scales, so the broadcast cannot durably disturb them.
 		{
 			Scalar speed = localVelocity.linearMotion.Length();
-			Scalar intensity = speed * (1.0f / 40.0f);
+			Scalar intensity = speed * (1.0f / 25.0f);	// full stomp by run speed (~25 u/s)
 			if (intensity > 1.0f) intensity = 1.0f;
-			if (intensity < 0.35f) intensity = 0.35f;	// audible floor (> the 0.3 transient drop gate)
+			if (intensity < 0.55f) intensity = 0.55f;	// a mech step is never subtle; floor well over the 0.3 drop gate
 			int runFamily = (state >= 0x0a && state <= 0x0f);	// wrr/wrl/rrr/rrl/rwr/rwl
 			Entity::AudioSocketIterator it(this);
 			Component *c;
 			while ((c = it.ReadAndNext()) != NULL)
 			{
-				// Feed ONLY the volume/brightness MIX stages (the footstep loudness
-				// inputs).  A blind broadcast misfires: mixers whose OUTPUT control
-				// is Start would forward the send as a Start and fire their sound
-				// per stride (the "chirp per step" bug -- ProgramButton clicked on
-				// every plant), and an AudioSource Fail()s on the 100+ input ids.
+				// Feed ONLY the volume/brightness mix stages WHOSE TARGET IS A
+				// FOOTSTEP SOURCE.  Two earlier bugs shaped this filter: a blind
+				// broadcast Start-fired sounds through Start-outputting mixers, and
+				// an output-only filter still cranked OTHER sounds' volume mixers
+				// (the always-on ambience pulsed to full step intensity -- the
+				// 'stuck button').  Identify footstep sources by their authored
+				// patch: FootFallInt/Ext live at bank2 patches 37/38/39 and bank1
+				// 106/107 (audiopresets.cpp, from the AUDIO1/2.RES soundfonts).
 				int cid = (int)c->GetClassID();
+				AudioComponent *tgt;
 				AudioControlID out;
 				if (cid == (int)RegisteredClass::AudioControlMixerClassID)
+				{
 					out = ((AudioControlMixer *)c)->GetOutputControlID();
+					tgt = ((AudioControlMixer *)c)->GetTargetComponent();
+				}
 				else if (cid == (int)RegisteredClass::AudioControlMultiplierClassID)
+				{
 					out = ((AudioControlMultiplier *)c)->GetOutputControlID();
+					tgt = ((AudioControlMultiplier *)c)->GetTargetComponent();
+				}
 				else
 					continue;
 				if (out != VolumeAudioControlID && out != BrightnessAudioControlID)
 					continue;
+				if (tgt == 0)
+					continue;
+				int tcid = (int)tgt->GetClassID();
+				if (tcid != 1001 && tcid != 1002 && tcid != 1005)	// Direct/Dyn3D/Static3D patch sources
+					continue;
+				PatchLevelOfDetail *lod = Cast_Object(PatchLevelOfDetail*,
+					((AudioSource *)tgt)->GetAudioResource()->PeekAudioLevelOfDetail());
+				if (lod == 0)
+					continue;
+				int b = lod->GetBankID(), pp = lod->GetPatchID();
+				Logical isFootfall =
+					(b == 2 && pp >= 37 && pp <= 39) || (b == 1 && (pp == 106 || pp == 107));
+				if (!isFootfall)
+					continue;
 				AudioComponent *ac = (AudioComponent *)c;
 				ac->ReceiveControl((AudioControlID)(runFamily ? 101 : 100), intensity);
 				ac->ReceiveControl((AudioControlID)(runFamily ? 100 : 101), 0.0f);