Method play

examples/src/Examples.hpp:1108–1265

struct ex_redalert_synthesis : public labsound_example
{
    virtual void play(int argc, char ** argv) override
    {
        const auto defaultAudioDeviceConfigurations = GetDefaultAudioDeviceConfiguration();
        context = lab::MakeRealtimeAudioContext(defaultAudioDeviceConfigurations.second, defaultAudioDeviceConfigurations.first);
        lab::AudioContext& ac = *context.get();

        std::shared_ptr<FunctionNode> sweep;
        std::shared_ptr<FunctionNode> outputGainFunction;

        std::shared_ptr<OscillatorNode> osc;
        std::shared_ptr<GainNode> oscGain;
        std::shared_ptr<OscillatorNode> resonator;
        std::shared_ptr<GainNode> resonatorGain;
        std::shared_ptr<GainNode> resonanceSum;

        std::shared_ptr<DelayNode> delay[5];

        std::shared_ptr<GainNode> delaySum;
        std::shared_ptr<GainNode> filterSum;

        std::shared_ptr<BiquadFilterNode> filter[5];

        {
            ContextRenderLock r(context.get(), "ex_redalert_synthesis");

            sweep = std::make_shared<FunctionNode>(ac, 1);
            sweep->setFunction([](ContextRenderLock & r, FunctionNode * me, int channel, float * values, size_t framesToProcess) {
                double dt = 1.0 / r.context()->sampleRate();
                double now = fmod(me->now(), 1.2f);

                for (size_t i = 0; i < framesToProcess; ++i)
                {
                    //0 to 1 in 900 ms with a 1200ms gap in between
                    if (now > 0.9)
                    {
                        values[i] = 487.f + 360.f;
                    }
                    else
                    {
                        values[i] = std::sqrt((float) now * 1.f / 0.9f) * 487.f + 360.f;
                    }

                    now += dt;
                }
            });

            sweep->start(0);

            outputGainFunction = std::make_shared<FunctionNode>(ac, 1);
            outputGainFunction->setFunction([](ContextRenderLock & r, FunctionNode * me, int channel, float * values, size_t framesToProcess) {
                double dt = 1.0 / r.context()->sampleRate();
                double now = fmod(me->now(), 1.2f);

                for (size_t i = 0; i < framesToProcess; ++i)
                {
                    //0 to 1 in 900 ms with a 1200ms gap in between
                    if (now > 0.9)
                    {