Carla/source/modules/juce_audio_processors/utilities/juce_AudioParameterFloat.h

/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

/**
    A subclass of AudioProcessorParameter that provides an easy way to create a
    parameter which maps onto a given NormalisableRange.

    @see AudioParameterInt, AudioParameterBool, AudioParameterChoice

    @tags{Audio}
*/
class JUCE_API  AudioParameterFloat  : public RangedAudioParameter
{
public:
    /** Creates a AudioParameterFloat with the specified parameters.

        @param parameterID         The parameter ID to use
        @param parameterName       The parameter name to use
        @param normalisableRange   The NormalisableRange to use
        @param defaultValue        The non-normalised default value
        @param parameterLabel      An optional label for the parameter's value
        @param parameterCategory   An optional parameter category
        @param stringFromValue     An optional lambda function that converts a non-normalised
                                   value to a string with a maximum length. This may
                                   be used by hosts to display the parameter's value.
        @param valueFromString     An optional lambda function that parses a string and
                                   converts it into a non-normalised value. Some hosts use
                                   this to allow users to type in parameter values.
    */
    AudioParameterFloat (const String& parameterID,
                         const String& parameterName,
                         NormalisableRange<float> normalisableRange,
                         float defaultValue,
                         const String& parameterLabel = String(),
                         Category parameterCategory = AudioProcessorParameter::genericParameter,
                         std::function<String(float value, int maximumStringLength)> stringFromValue = nullptr,
                         std::function<float(const String& text)> valueFromString = nullptr);

    /** Creates a AudioParameterFloat with an ID, name, and range.
        On creation, its value is set to the default value.
        For control over skew factors, you can use the other
        constructor and provide a NormalisableRange.
    */
    AudioParameterFloat (String parameterID,
                         String parameterName,
                         float minValue,
                         float maxValue,
                         float defaultValue);

    /** Destructor. */
    ~AudioParameterFloat() override;

    /** Returns the parameter's current value. */
    float get() const noexcept                  { return value; }

    /** Returns the parameter's current value. */
    operator float() const noexcept             { return value; }

    /** Changes the parameter's current value. */
    AudioParameterFloat& operator= (float newValue);

    /** Returns the range of values that the parameter can take. */
    const NormalisableRange<float>& getNormalisableRange() const override   { return range; }

    /** Provides access to the parameter's range. */
    NormalisableRange<float> range;

protected:
    /** Override this method if you are interested in receiving callbacks
        when the parameter value changes.
    */
    virtual void valueChanged (float newValue);

private:
    //==============================================================================
    float getValue() const override;
    void setValue (float newValue) override;
    float getDefaultValue() const override;
    int getNumSteps() const override;
    String getText (float, int) const override;
    float getValueForText (const String&) const override;

    std::atomic<float> value;
    const float defaultValue;
    std::function<String(float, int)> stringFromValueFunction;
    std::function<float(const String&)> valueFromStringFunction;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (AudioParameterFloat)
};

} // namespace juce