From 4f3c4a531227fec3ea77e5ee6978e676240f53e0 Mon Sep 17 00:00:00 2001
From: David Rowe <david@ctrlaltstudio.com>
Date: Mon, 10 Aug 2015 12:52:47 -0700
Subject: [PATCH] Tidy up handling of eye tracker streaming

---
 interface/src/devices/EyeTracker.cpp | 14 +++++++++-----
 interface/src/devices/EyeTracker.h   |  1 +
 2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/interface/src/devices/EyeTracker.cpp b/interface/src/devices/EyeTracker.cpp
index 9a35448bd0..7620dc070f 100644
--- a/interface/src/devices/EyeTracker.cpp
+++ b/interface/src/devices/EyeTracker.cpp
@@ -29,9 +29,11 @@ static void CALLBACK eyeTrackerCallback(smi_CallbackDataStruct* data) {
 
 EyeTracker::~EyeTracker() {
 #ifdef HAVE_IVIEWHMD
-    int result = smi_quit();
-    if (result != SMI_RET_SUCCESS) {
-        qCWarning(interfaceapp) << "Eye Tracker: Error terminating tracking:" << smiReturnValueToString(result);
+    if (_isStreaming) {
+        int result = smi_quit();
+        if (result != SMI_RET_SUCCESS) {
+            qCWarning(interfaceapp) << "Eye Tracker: Error terminating tracking:" << smiReturnValueToString(result);
+        }
     }
 #endif
 }
@@ -131,16 +133,18 @@ void EyeTracker::setEnabled(bool enabled, bool simulate) {
     qCDebug(interfaceapp) << "Eye Tracker: Set enabled =" << enabled << ", simulate =" << simulate;
     bool success = true;
     int result = 0;
-    if (enabled) {
+    if (enabled && !_isStreaming) {
         // There is no smi_stopStreaming() method so keep streaming once started in case tracking is re-enabled after stopping.
         result = smi_startStreaming(simulate);
         if (result != SMI_RET_SUCCESS) {
             qCWarning(interfaceapp) << "Eye Tracker: Error starting streaming:" << smiReturnValueToString(result);
             success = false;
         }
+
+        _isStreaming = success;
     }
 
-    _isEnabled = enabled && success;
+    _isEnabled = enabled && _isStreaming;
     _isSimulating = _isEnabled && simulate;
 
     if (!success && result != SMI_ERROR_HMD_NOT_SUPPORTED) {
diff --git a/interface/src/devices/EyeTracker.h b/interface/src/devices/EyeTracker.h
index 4976c14d08..b1c71c0303 100644
--- a/interface/src/devices/EyeTracker.h
+++ b/interface/src/devices/EyeTracker.h
@@ -50,6 +50,7 @@ private:
     QString smiReturnValueToString(int value);
     
     bool _isInitialized = false;
+    bool _isStreaming = false;
     bool _isEnabled = false;
     bool _isSimulating = false;