Change the force feedback driver to use mach_absolute_time instead of CFAbsoluteTimeGetCurrent.

Fixes 360Controller#70

Author: MaddTheSane

360 Driver.xcodeproj/project.pbxproj

@@ -297,7 +297,6 @@
 		55E1C62819708E7300EC9DD8 /* build.sh */ = {isa = PBXFileReference; lastKnownFileType = text.script.sh; path = build.sh; sourceTree = SOURCE_ROOT; };
 		55E1C62919708E7300EC9DD8 /* clean.sh */ = {isa = PBXFileReference; lastKnownFileType = text.script.sh; path = clean.sh; sourceTree = SOURCE_ROOT; };
 		55E1C62A19708F8600EC9DD8 /* Readme.md */ = {isa = PBXFileReference; lastKnownFileType = text; path = Readme.md; sourceTree = SOURCE_ROOT; };
-		55E1C62B1970921E00EC9DD8 /* Readme.rtf */ = {isa = PBXFileReference; lastKnownFileType = text.rtf; path = Readme.rtf; sourceTree = SOURCE_ROOT; };
 		55FE3CA118D7B77800D69E84 /* testhaptic */ = {isa = PBXFileReference; explicitFileType = "compiled.mach-o.executable"; includeInIndex = 0; path = testhaptic; sourceTree = BUILT_PRODUCTS_DIR; };
 		55FE3CAC18D7B7B600D69E84 /* SDL2.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = SDL2.framework; path = /Library/Frameworks/SDL2.framework; sourceTree = "<absolute>"; };
 /* End PBXFileReference section */
@@ -402,7 +401,6 @@
 			isa = PBXGroup;
 			children = (
 				55E1C62A19708F8600EC9DD8 /* Readme.md */,
-				55E1C62B1970921E00EC9DD8 /* Readme.rtf */,
 				551CE004196EFD34000869B6 /* Welcome.rtf */,
 			);
 			path = Text;

Feedback360/Feedback360.cpp

@@ -24,11 +24,27 @@
  */
 
 #include "Feedback360.h"
+#include <mach/mach.h>
+#include <mach/mach_time.h>
 using std::max;
 using std::min;
 
 #define LoopGranularity 10000 // Microseconds
 
+double CurrentTimeUsingMach()
+{
+    mach_timebase_info_data_t info = {0};
+	if (mach_timebase_info(&info) != KERN_SUCCESS) {
+		//FIXME: why would this fail/set to fail more gracefully.
+        return -1.0;
+	}
+	
+    uint64_t start = mach_absolute_time();
+
+    uint64_t nanos = start * info.numer / info.denom;
+    return (double)nanos / NSEC_PER_SEC;
+}
+
 static IOCFPlugInInterface functionMap360_IOCFPlugInInterface = {
     // Padding required for COM
     NULL,
@@ -186,7 +202,7 @@ HRESULT Feedback360::StartEffect(FFEffectDownloadID EffectHandle, FFEffectStartF
             {
                 effectIterator->Status  = FFEGES_PLAYING;
                 effectIterator->PlayCount = Count;
-                effectIterator->StartTime = CFAbsoluteTimeGetCurrent();
+                effectIterator->StartTime = CurrentTimeUsingMach();
                 Stopped = false;
             } else {
                 if (Mode & FFES_SOLO) {
@@ -336,7 +352,7 @@ HRESULT Feedback360::DownloadEffect(CFUUIDRef EffectType, FFEffectDownloadID *Ef
             {
                 Effect->Status  = FFEGES_PLAYING;
                 Effect->PlayCount = 1;
-                Effect->StartTime = CFAbsoluteTimeGetCurrent();
+                Effect->StartTime = CurrentTimeUsingMach();
             }
 
             if( Flags & FFEP_NORESTART )
@@ -438,13 +454,13 @@ HRESULT Feedback360::SendForceFeedbackCommand(FFCommandFlag state)
 
             case FFSFFC_PAUSE:
                 Paused  = true;
-                PausedTime = CFAbsoluteTimeGetCurrent();
+                PausedTime = CurrentTimeUsingMach();
                 break;
 
             case FFSFFC_CONTINUE:
                 for (Feedback360EffectIterator effectIterator = EffectList.begin() ; effectIterator != EffectList.end(); ++effectIterator)
                 {
-                    effectIterator->StartTime += ( CFAbsoluteTimeGetCurrent() - PausedTime );
+                    effectIterator->StartTime += ( CurrentTimeUsingMach() - PausedTime );
                 }
                 Paused = false;
                 break;
@@ -591,7 +607,7 @@ void Feedback360::EffectProc( void *params )
     {
         for (Feedback360EffectIterator effectIterator = cThis->EffectList.begin(); effectIterator != cThis->EffectList.end(); ++effectIterator)
         {
-            if((CFAbsoluteTimeGetCurrent() - cThis->LastTime*1000*1000) >= effectIterator->DiEffect.dwSamplePeriod) {
+            if((CurrentTimeUsingMach() - cThis->LastTime*1000*1000) >= effectIterator->DiEffect.dwSamplePeriod) {
                 CalcResult = effectIterator->Calc(&LeftLevel, &RightLevel);
             }
         }

Feedback360/Feedback360.h

@@ -114,8 +114,8 @@ class Feedback360 : IUnknown
     bool            Stopped;
     bool            Paused;
     bool            Manual;
-    CFAbsoluteTime  LastTime;
-    CFAbsoluteTime  PausedTime;
+    double          LastTime;
+    double          PausedTime;
     CFUUIDRef       FactoryID;
 
     void            SetForce(LONG LeftLevel, LONG RightLevel);

Feedback360/Feedback360Effect.cpp

@@ -65,13 +65,13 @@ LONG Feedback360Effect::Calc(LONG *LeftLevel, LONG *RightLevel)
     } else {
         Duration = DBL_MAX;
     }
-    CFAbsoluteTime BeginTime = StartTime + ( DiEffect.dwStartDelay / 1000. / 1000.);
-    CFAbsoluteTime EndTime  = DBL_MAX;
+    double BeginTime = StartTime + ( DiEffect.dwStartDelay / 1000. / 1000.);
+    double EndTime  = DBL_MAX;
     if (PlayCount != -1)
     {
         EndTime = BeginTime + Duration * PlayCount;
     }
-    CFAbsoluteTime CurrentTime = CFAbsoluteTimeGetCurrent();
+    double CurrentTime = CurrentTimeUsingMach();
 
     if (Status == FFEGES_PLAYING && BeginTime <= CurrentTime && CurrentTime <= EndTime)
     {
@@ -93,15 +93,15 @@ LONG Feedback360Effect::Calc(LONG *LeftLevel, LONG *RightLevel)
 
         // CustomForce allows setting each channel separately
         if(CFEqual(Type, kFFEffectType_CustomForce_ID)) {
-            if((CFAbsoluteTimeGetCurrent() - LastTime)*1000*1000 < DiCustomForce.dwSamplePeriod) {
+            if((CurrentTimeUsingMach() - LastTime)*1000*1000 < DiCustomForce.dwSamplePeriod) {
                 return -1;
             }
             else {
                 WorkLeftLevel = ((DiCustomForce.rglForceData[2*Index] * NormalRate + AttackLevel + FadeLevel) / 100) * DiEffect.dwGain / 10000;
                 WorkRightLevel = ((DiCustomForce.rglForceData[2*Index + 1] * NormalRate + AttackLevel + FadeLevel) / 100) * DiEffect.dwGain / 10000;
                 //fprintf(stderr, "L:%d; R:%d\n", WorkLeftLevel, WorkRightLevel);
                 Index = (Index + 1) % (DiCustomForce.cSamples/2);
-                LastTime = CFAbsoluteTimeGetCurrent();
+                LastTime = CurrentTimeUsingMach();
             }
         }
         // Regular commands treat controller as a single output (both channels are together as one)

Feedback360/Feedback360Effect.h

@@ -53,6 +53,8 @@
 
 #define SCALE_MAX (LONG)255
 
+double CurrentTimeUsingMach();
+
 class Feedback360Effect
 {
 public:
@@ -73,9 +75,9 @@ class Feedback360Effect
 
     DWORD			Status;
     DWORD			PlayCount;
-    CFAbsoluteTime	StartTime;
+    double			StartTime;
 
-    CFAbsoluteTime  LastTime;
+    double			LastTime;
     DWORD           Index;
 
 private: