From 5527d4b50ff729bedd2d5bf02d35e3bb81f42510 Mon Sep 17 00:00:00 2001
From: Stephen Birarda <commit@birarda.com>
Date: Thu, 11 Jul 2013 10:51:56 -0700
Subject: [PATCH] use glm clamp instead of pleateauAdditionOfSamples in audio
 mixer

---
 audio-mixer/src/main.cpp | 75 ++++++++++++++++++++--------------------
 1 file changed, 38 insertions(+), 37 deletions(-)

diff --git a/audio-mixer/src/main.cpp b/audio-mixer/src/main.cpp
index 68d66ac7ac..67ccb47e8c 100644
--- a/audio-mixer/src/main.cpp
+++ b/audio-mixer/src/main.cpp
@@ -6,42 +6,45 @@
 //  Copyright (c) 2013 High Fidelity, Inc. All rights reserved.
 //
 
+#include <errno.h>
+#include <fcntl.h>
+#include <fstream>
 #include <iostream>
+#include <limits>
 #include <math.h>
-#include <string.h>
+#include <signal.h>
 #include <stdio.h>
 #include <stdlib.h>
-#include <fcntl.h>
-#include <errno.h>
-#include <fstream>
-#include <limits>
-#include <signal.h>
-
-#include <glm/gtx/norm.hpp>
-#include <glm/gtx/vector_angle.hpp>
-#include <NodeList.h>
-#include <Node.h>
-#include <NodeTypes.h>
-#include <SharedUtil.h>
-#include <StdDev.h>
-#include <Logstash.h>
-
-#include "InjectedAudioRingBuffer.h"
-#include "AvatarAudioRingBuffer.h"
-#include <AudioRingBuffer.h>
-#include "PacketHeaders.h"
+#include <string.h>
 
 #ifdef _WIN32
 #include "Syssocket.h"
 #include "Systime.h"
 #include <math.h>
 #else
+#include <arpa/inet.h>
+#include <netinet/in.h>
 #include <sys/time.h>
 #include <sys/socket.h>
-#include <netinet/in.h>
-#include <arpa/inet.h>
 #endif //_WIN32
 
+#include <glm/glm.hpp>
+#include <glm/gtx/norm.hpp>
+#include <glm/gtx/vector_angle.hpp>
+
+#include <Logstash.h>
+#include <NodeList.h>
+#include <Node.h>
+#include <NodeTypes.h>
+#include <PacketHeaders.h>
+#include <SharedUtil.h>
+#include <StdDev.h>
+
+#include <AudioRingBuffer.h>
+
+#include "AvatarAudioRingBuffer.h"
+#include "InjectedAudioRingBuffer.h"
+
 const unsigned short MIXER_LISTEN_PORT = 55443;
 
 const short JITTER_BUFFER_MSECS = 12;
@@ -49,17 +52,8 @@ const short JITTER_BUFFER_SAMPLES = JITTER_BUFFER_MSECS * (SAMPLE_RATE / 1000.0)
 
 const unsigned int BUFFER_SEND_INTERVAL_USECS = floorf((BUFFER_LENGTH_SAMPLES_PER_CHANNEL / SAMPLE_RATE) * 1000000);
 
-const long MAX_SAMPLE_VALUE = std::numeric_limits<int16_t>::max();
-const long MIN_SAMPLE_VALUE = std::numeric_limits<int16_t>::min();
-
-void plateauAdditionOfSamples(int16_t &mixSample, int16_t sampleToAdd) {
-    long sumSample = sampleToAdd + mixSample;
-    
-    long normalizedSample = std::min(MAX_SAMPLE_VALUE, sumSample);
-    normalizedSample = std::max(MIN_SAMPLE_VALUE, sumSample);
-    
-    mixSample = normalizedSample;
-}
+const int MAX_SAMPLE_VALUE = std::numeric_limits<int16_t>::max();
+const int MIN_SAMPLE_VALUE = std::numeric_limits<int16_t>::min();
 
 void attachNewBufferToNode(Node *newNode) {
     if (!newNode->getLinkedData()) {
@@ -304,16 +298,23 @@ int main(int argc, const char* argv[]) {
                                 // pull the earlier sample for the delayed channel
                                 int earlierSample = delaySamplePointer[s] * attenuationCoefficient * weakChannelAmplitudeRatio;
                                 
-                                plateauAdditionOfSamples(delayedChannel[s], earlierSample);
+                                delayedChannel[s] = glm::clamp(delayedChannel[s] + earlierSample,
+                                                               MIN_SAMPLE_VALUE,
+                                                               MAX_SAMPLE_VALUE);
                             }
                             
                             int16_t currentSample = stkFrameBuffer[s] * attenuationCoefficient;
                             
-                            plateauAdditionOfSamples(goodChannel[s], currentSample);
+                            goodChannel[s] = glm::clamp(goodChannel[s] + currentSample,
+                                                        MIN_SAMPLE_VALUE,
+                                                        MAX_SAMPLE_VALUE);
                             
                             if (s + numSamplesDelay < BUFFER_LENGTH_SAMPLES_PER_CHANNEL) {
-                                plateauAdditionOfSamples(delayedChannel[s + numSamplesDelay],
-                                                         currentSample * weakChannelAmplitudeRatio);
+                                int sumSample = delayedChannel[s + numSamplesDelay]
+                                    + (currentSample * weakChannelAmplitudeRatio);
+                                delayedChannel[s + numSamplesDelay] = glm::clamp(sumSample,
+                                                                                 MIN_SAMPLE_VALUE,
+                                                                                 MAX_SAMPLE_VALUE);
                             }
                             
                             if (s >= BUFFER_LENGTH_SAMPLES_PER_CHANNEL - PHASE_DELAY_AT_90) {