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/*
==============================================================================
This file was auto-generated!
==============================================================================
*/
#ifndef MAINCOMPONENT_H_INCLUDED
#define MAINCOMPONENT_H_INCLUDED
#include "../JuceLibraryCode/JuceHeader.h"
//==============================================================================
class MainContentComponent : public AudioAppComponent
{
public:
//==============================================================================
MainContentComponent()
: phase (0.0f),
phaseDelta (0.0f),
frequency (5000.0f),
amplitude (0.2f),
sampleRate (0.0),
expectedSamplesPerBlock (0)
{
setSize (800, 600);
// Specify the number of input and output channels that we want to open.
setAudioChannels (0, 2);
}
~MainContentComponent()
{
shutdownAudio();
}
//==============================================================================
void prepareToPlay (int samplesPerBlockExpected, double newSampleRate) override
{
sampleRate = newSampleRate;
expectedSamplesPerBlock = samplesPerBlockExpected;
}
/* This method generates the actual audio samples.
In this example the buffer is filled with a sine wave whose frequency and
amplitude are controlled by the mouse position.
*/
void getNextAudioBlock (const AudioSourceChannelInfo& bufferToFill) override
{
bufferToFill.clearActiveBufferRegion();
const float originalPhase = phase;
for (int chan = 0; chan < bufferToFill.buffer->getNumChannels(); ++chan)
{
phase = originalPhase;
float* const channelData = bufferToFill.buffer->getWritePointer (chan, bufferToFill.startSample);
for (int i = 0; i < bufferToFill.numSamples ; ++i)
{
channelData[i] = amplitude * std::sin (phase);
// increment the phase step for the next sample
phase = std::fmod (phase + phaseDelta, float_Pi * 2.0f);
}
}
}
void releaseResources() override
{
// This gets automatically called when audio device parameters change
// or device is restarted.
}
//==============================================================================
void paint (Graphics& g) override
{
// (Our component is opaque, so we must completely fill the background with a solid colour)
g.fillAll (Colours::black);
const float centreY = getHeight() / 2.0f;
const float radius = amplitude * 200.0f;
// Draw an ellipse based on the mouse position and audio volume
g.setColour (Colours::lightgreen);
g.fillEllipse (lastMousePosition.x - radius / 2.0f,
lastMousePosition.y - radius / 2.0f,
radius, radius);
// Draw a representative sine wave.
Path wavePath;
wavePath.startNewSubPath (0, centreY);
for (float x = 1.0f; x < getWidth(); ++x)
wavePath.lineTo (x, centreY + amplitude * getHeight() * 2.0f
* std::sin (x * frequency * 0.0001f));
g.setColour (Colours::grey);
g.strokePath (wavePath, PathStrokeType (2.0f));
}
// Mouse handling..
void mouseDown (const MouseEvent& e) override
{
mouseDrag (e);
}
void mouseDrag (const MouseEvent& e) override
{
lastMousePosition = e.position;
frequency = (getHeight() - e.y) * 10.0f;
amplitude = jmin (0.9f, 0.2f * e.position.x / getWidth());
phaseDelta = (float) (2.0 * double_Pi * frequency / sampleRate);
repaint();
}
void mouseUp (const MouseEvent&) override
{
amplitude = 0.0f;
repaint();
}
void resized() override
{
// This is called when the MainContentComponent is resized.
// If you add any child components, this is where you should
// update their positions.
}
private:
//==============================================================================
float phase;
float phaseDelta;
float frequency;
float amplitude;
double sampleRate;
int expectedSamplesPerBlock;
Point<float> lastMousePosition;
JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (MainContentComponent)
};
Component* createMainContentComponent() { return new MainContentComponent(); };
#endif // MAINCOMPONENT_H_INCLUDED
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