ExternalData

HISE has a few complex inbuilt data structures that are connected to various UI elements (Tables, SliderPacks) etc.
The access to those classes and their underlying data is handled by this class.
This class is used as parameter in the setExternalData callback, which will be called whenever something changes.
It's usually good practice to keep a copy of the last ExternalData around in your class to refer blocks to it or synchronize access using a DataReadLock or - more unusual - DataWriteLock.

Public types

enum DataType

Name	Description
Table	the data of a Table object (a look up table with 512 float numbers)
SliderPack	the data of a SliderPack (a resizable array of float numbers)
AudioFile	a multichannel audio file with some metadata (loop points, samplerate).
FilterCoefficients	filter coefficients that can be used for displaying purposes
DisplayBuffer	a FIFO buffer that can be used for analysing / visualisations

Class members

dataType

DataType dataType = DataType::numDataTypes

the data type of the target data.

numSamples

int numSamples = 0

The number of samples (= the length of the float array)

numChannels

int numChannels = 0

The number of audio channels (usually 1 if not an audio file).

isXYZAudioData

int isXYZAudioData = 0

Specifies whether the data points to a multichannel sample set.

data

void* data = nullptr

An untyped pointer to the actual data.

obj

hise::ComplexDataUIBase* obj = nullptr

A pointer to the complex data object that is used for eg. UI updates.

sampleRate

double sampleRate = 0.0

the samplerate (if the data is an audio file).

Class methods

ExternalData

template   ExternalData(T &other, DataType type)

Creates an external data object from a constant value class.

referBlockTo

void referBlockTo(block &b, int channelIndex) const

assigns a block container to the data type. If the external data is pointing to an audio file you can specify the channelIndex.

setDisplayedValue

void setDisplayedValue(double valueToDisplay)

This will send a update message to the UI so you can implement eg. a playback position.

isEmpty

bool isEmpty() const

Returns true if there is no data associated with this object.

isXYZ

bool isXYZ() const

If the ExternalData object points to audio data this specifies whether it's a multisample set or a single sample.