robert@464: /*
robert@464:  ____  _____ _        _    
robert@464: | __ )| ____| |      / \   
robert@464: |  _ \|  _| | |     / _ \  
robert@464: | |_) | |___| |___ / ___ \ 
robert@464: |____/|_____|_____/_/   \_\
robert@464: 
robert@464: The platform for ultra-low latency audio and sensor processing
robert@464: 
robert@464: http://bela.io
robert@464: 
robert@464: A project of the Augmented Instruments Laboratory within the
robert@464: Centre for Digital Music at Queen Mary University of London.
robert@464: http://www.eecs.qmul.ac.uk/~andrewm
robert@464: 
robert@464: (c) 2016 Augmented Instruments Laboratory: Andrew McPherson,
robert@464:     Astrid Bin, Liam Donovan, Christian Heinrichs, Robert Jack,
robert@464:     Giulio Moro, Laurel Pardue, Victor Zappi. All rights reserved.
robert@464: 
robert@464: The Bela software is distributed under the GNU Lesser General Public License
robert@464: (LGPL 3.0), available here: https://www.gnu.org/licenses/lgpl-3.0.txt
robert@464: */
robert@464: 
robert@464: #include <Bela.h>
robert@464: #include <Scope.h>
robert@464: #include <cmath>
robert@464: 
robert@464: // set the frequency of the oscillators
robert@464: float gFrequency = 110.0;
robert@464: float gPhase;
robert@464: float gInverseSampleRate;
robert@464: 
robert@464: // instantiate the scope
robert@464: Scope scope;
robert@464: 
robert@464: bool setup(BelaContext *context, void *userData)
robert@464: {
robert@464:     // tell the scope how many channels and the sample rate
robert@464:     scope.setup(3, context->audioSampleRate);
robert@464: 
robert@464:     gPhase = 0;
robert@464:     gInverseSampleRate = 1.0f/context->audioSampleRate;
robert@464:     
robert@464: 	return true;
robert@464: }
robert@464: 
robert@464: float lastOut = 0.0;
robert@464: float lastOut2 = 0.0;
robert@464: void render(BelaContext *context, void *userData)
robert@464: {
robert@464:     // iterate over the audio frames and create three oscillators, seperated in phase by PI/2
robert@464:     for (unsigned int n=0; n<context->audioFrames; n++){
robert@464:         float out = 0.8f * sinf(gPhase);
robert@464:         float out2 = 0.8f * sinf(gPhase - M_PI/2);
robert@464: 		float out3 = 0.8f * sinf(gPhase + M_PI/2);
robert@464: 		gPhase += 2.0 * M_PI * gFrequency * gInverseSampleRate;
robert@464: 		if(gPhase > 2.0 * M_PI)
robert@464: 			gPhase -= 2.0 * M_PI;
robert@464: 			
robert@464: 		// log the three oscillators to the scope
robert@464:         scope.log(out, out2, out3);
robert@464:         
robert@464:         // optional - tell the scope to trigger when oscillator 1 becomes less than oscillator 2
robert@464:         // note this has no effect unless trigger mode is set to custom in the scope UI
robert@464:         if (lastOut >= lastOut2 && out < out2){
robert@464:             scope.trigger();
robert@464:         }
robert@464:         
robert@464:         lastOut = out;
robert@464:         lastOut2 = out2;
robert@464:     }
robert@464: }
robert@464: 
robert@464: void cleanup(BelaContext *context, void *userData)
robert@464: {
robert@464: 
robert@464: }
robert@464: 
robert@464: /* ------------ Project Explantation ------------ */
robert@464: 
robert@464: /**
robert@464: \example 01-scope
robert@464: 
robert@464: Oscilloscope in-browser
robert@464: -----------------------
robert@464: 
robert@464: This example demonstrates the scope feature of the IDE.
robert@464: 
robert@464: The scope is instantiated at the top of the file via `Scope scope;`
robert@464: 
robert@464: In `setup()` we define how many channels the scope should have and the sample 
robert@464: rate that it should run at via `scope.setup(3, context->audioSampleRate)`.
robert@464: 
robert@464: In `render()` we choose what the scope log via `scope.log(out, out2, out3)`. 
robert@464: In this example the scope is logging three sine waves with different phases. To see
robert@464: the output click on the <b>Open Scope</b> button.
robert@464: 
robert@464: An additional option is to set the trigger of the oscilloscope from within `render()`.
robert@464: In this example we are triggering the scope when oscillator 1 becomes less than 
robert@464: oscillator 2 via `scope.trigger()`. Note that this functionality only takes effect
robert@464: when the triggering mode is set to custom in the scope UI.
robert@464: */