comparison examples/01-Basics/scope/render.cpp @ 468:85cf9c0da052 prerelease

merge

+/*
+ ____  _____ _        _    
+| __ )| ____| |      / \   
+|  _ \|  _| | |     / _ \  
+| |_) | |___| |___ / ___ \ 
+|____/|_____|_____/_/   \_\
+
+The platform for ultra-low latency audio and sensor processing
+
+http://bela.io
+
+A project of the Augmented Instruments Laboratory within the
+Centre for Digital Music at Queen Mary University of London.
+http://www.eecs.qmul.ac.uk/~andrewm
+
+(c) 2016 Augmented Instruments Laboratory: Andrew McPherson,
+    Astrid Bin, Liam Donovan, Christian Heinrichs, Robert Jack,
+    Giulio Moro, Laurel Pardue, Victor Zappi. All rights reserved.
+
+The Bela software is distributed under the GNU Lesser General Public License
+(LGPL 3.0), available here: https://www.gnu.org/licenses/lgpl-3.0.txt
+*/
+
+#include <Bela.h>
+#include <Scope.h>
+#include <cmath>
+
+// set the frequency of the oscillators
+float gFrequency = 110.0;
+float gPhase;
+float gInverseSampleRate;
+
+// instantiate the scope
+Scope scope;
+
+bool setup(BelaContext *context, void *userData)
+{
+    // tell the scope how many channels and the sample rate
+    scope.setup(3, context->audioSampleRate);
+
+    gPhase = 0;
+    gInverseSampleRate = 1.0f/context->audioSampleRate;
+    
+	return true;
+}
+
+float lastOut = 0.0;
+float lastOut2 = 0.0;
+void render(BelaContext *context, void *userData)
+{
+    // iterate over the audio frames and create three oscillators, seperated in phase by PI/2
+    for (unsigned int n=0; n<context->audioFrames; n++){
+        float out = 0.8f * sinf(gPhase);
+        float out2 = 0.8f * sinf(gPhase - M_PI/2);
+		float out3 = 0.8f * sinf(gPhase + M_PI/2);
+		gPhase += 2.0 * M_PI * gFrequency * gInverseSampleRate;
+		if(gPhase > 2.0 * M_PI)
+			gPhase -= 2.0 * M_PI;
+			
+		// log the three oscillators to the scope
+        scope.log(out, out2, out3);
+        
+        // optional - tell the scope to trigger when oscillator 1 becomes less than oscillator 2
+        // note this has no effect unless trigger mode is set to custom in the scope UI
+        if (lastOut >= lastOut2 && out < out2){
+            scope.trigger();
+        }
+        
+        lastOut = out;
+        lastOut2 = out2;
+    }
+}
+
+void cleanup(BelaContext *context, void *userData)
+{
+
+}
+
+/* ------------ Project Explantation ------------ */
+
+/**
+\example 01-scope
+
+Oscilloscope in-browser
+-----------------------
+
+This example demonstrates the scope feature of the IDE.
+
+The scope is instantiated at the top of the file via `Scope scope;`
+
+In `setup()` we define how many channels the scope should have and the sample 
+rate that it should run at via `scope.setup(3, context->audioSampleRate)`.
+
+In `render()` we choose what the scope log via `scope.log(out, out2, out3)`. 
+In this example the scope is logging three sine waves with different phases. To see
+the output click on the <b>Open Scope</b> button.
+
+An additional option is to set the trigger of the oscilloscope from within `render()`.
+In this example we are triggering the scope when oscillator 1 becomes less than 
+oscillator 2 via `scope.trigger()`. Note that this functionality only takes effect
+when the triggering mode is set to custom in the scope UI.
+*/