stat bars with no stats now show n/a instead of o

indra/llcommon/lltracerecording.h

@@ -333,6 +333,21 @@ namespace LLTrace
 		const Recording& getPrevRecording(U32 offset) const;
 		Recording snapshotCurRecording() const;
 
+		template <typename T>
+		size_t getSampleCount(const TraceType<T>& stat, size_t num_periods = U32_MAX)
+        {
+			size_t total_periods = mNumPeriods;
+			num_periods = llmin(num_periods, isStarted() ? total_periods - 1 : total_periods);
+
+            size_t num_samples = 0;
+			for (S32 i = 1; i <= num_periods; i++)
+			{
+				S32 index = (mCurPeriod + total_periods - i) % total_periods;
+				num_samples += mRecordingPeriods[index].getSampleCount(stat);
+			}
+			return num_samples;
+        }
+        
 		//
 		// PERIODIC MIN
 		//

indra/llui/llstatbar.cpp

@@ -225,6 +225,9 @@ void LLStatBar::draw()
 		max     = 0,
 		mean    = 0;
 
+    
+    S32 num_samples = 0;
+    
 	LLLocalClipRect _(getLocalRect());
 	LLTrace::PeriodicRecording& frame_recording = LLTrace::get_frame_recording();
 
@@ -236,6 +239,7 @@ void LLStatBar::draw()
 		if (mPerSec)
 		{
 			unit_label += "/s";
+            num_samples = frame_recording.getSampleCount(*mCountFloatp, mNumFrames);
 			current = last_frame_recording.getPerSec(*mCountFloatp);
 			min     = frame_recording.getPeriodMinPerSec(*mCountFloatp, mNumFrames);
 			max     = frame_recording.getPeriodMaxPerSec(*mCountFloatp, mNumFrames);
@@ -243,6 +247,7 @@ void LLStatBar::draw()
 		}
 		else
 		{
+            num_samples = frame_recording.getSampleCount(*mCountFloatp, mNumFrames);
 			current = last_frame_recording.getSum(*mCountFloatp);
 			min     = frame_recording.getPeriodMin(*mCountFloatp, mNumFrames);
 			max     = frame_recording.getPeriodMax(*mCountFloatp, mNumFrames);
@@ -254,6 +259,7 @@ void LLStatBar::draw()
 		LLTrace::Recording& last_frame_recording = frame_recording.getLastRecording();
 		unit_label = mUnitLabel.empty() ? mEventFloatp->getUnitLabel() : mUnitLabel;
 
+        num_samples = frame_recording.getSampleCount(*mEventFloatp, mNumFrames);
 		current = last_frame_recording.getMean(*mEventFloatp);
 		min     = frame_recording.getPeriodMin(*mEventFloatp, mNumFrames);
 		max     = frame_recording.getPeriodMax(*mEventFloatp, mNumFrames);
@@ -264,6 +270,7 @@ void LLStatBar::draw()
 		LLTrace::Recording& last_frame_recording = frame_recording.getLastRecording();
 		unit_label = mUnitLabel.empty() ? mSampleFloatp->getUnitLabel() : mUnitLabel;
 
+        num_samples = frame_recording.getSampleCount(*mSampleFloatp, mNumFrames);
 		current = last_frame_recording.getMean(*mSampleFloatp);
 		min     = frame_recording.getPeriodMin(*mSampleFloatp, mNumFrames);
 		max     = frame_recording.getPeriodMax(*mSampleFloatp, mNumFrames);
@@ -329,7 +336,9 @@ void LLStatBar::draw()
 	{
 		decimal_digits = 0;
 	}
-	std::string value_str = llformat("%10.*f %s", decimal_digits, mean, unit_label.c_str());
+	std::string value_str = num_samples
+                            ? llformat("%10.*f %s", decimal_digits, mean, unit_label.c_str())
+                            : "n/a";
 
 	// Draw the current value.
 	if (mOrientation == HORIZONTAL)
@@ -345,7 +354,8 @@ void LLStatBar::draw()
 			LLFontGL::RIGHT, LLFontGL::TOP);
 	}
 
-	if (mDisplayBar && (mCountFloatp || mEventFloatp || mSampleFloatp))
+	if (mDisplayBar
+        && (mCountFloatp || mEventFloatp || mSampleFloatp))
 	{
 		// Draw the tick marks.
 		LLGLSUIDefault gls_ui;
@@ -431,7 +441,6 @@ void LLStatBar::draw()
 		if (begin < 0)
 		{
 			begin = 0;
-			llwarns << "Min:" << min << llendl;
 		}
 
 		S32 end = (S32) ((max - mCurMinBar) * value_scale);
@@ -444,6 +453,8 @@ void LLStatBar::draw()
 			gl_rect_2d(begin, bar_top, end, bar_bottom, LLColor4(1.f, 0.f, 0.f, 0.25f));
 		}
 
+        if (num_samples)
+        {
             F32 span = (mOrientation == HORIZONTAL)
 					? (bar_right - bar_left)
 					: (bar_top - bar_bottom);
@@ -529,6 +540,7 @@ void LLStatBar::draw()
                 }
             }
         }
+	}
 	
 	LLView::draw();
 }