first draft of the SampleBundle.at() function. issue #70

include/core/JamomaSample.h

@@ -111,6 +111,25 @@ namespace Jamoma {
 		{
 			return const_cast<SampleBundle*>(this)->mChannels[index];
 		}
+
+
+        /** Interpolate a value between known Samples.
+         */
+        Sample at(size_t channel, double interpolatedFrameIndex) {
+            Sample output = 0.0;
+            Jamoma::Interpolator::Linear<Sample> my_interp;
+
+            int frameIndexBefore = (int)interpolatedFrameIndex;
+            double delta = interpolatedFrameIndex - frameIndexBefore;
+            int frameIndexAfter = frameIndexBefore + 1;
+
+            Sample sampleAtIndexBefore = mChannels[channel][frameIndexBefore];
+            Sample sampleAtIndexAfter = mChannels[channel][frameIndexAfter];
+
+            output = my_interp(sampleAtIndexBefore,sampleAtIndexAfter,delta);
+
+            return output;
+        }
 
 
 		/**	Change the channel count of the bundle.