C++:
VstIntPtr function audioMasterCallback(AEffect* e, VstInt32 opcode, VstInt32 index, VstIntPtr value,
void* ptr, float opt);
Delphi:
function audioMasterCallback(e: PAEffect; opcode, index: VstInt32; value: VstIntPtr; ptr: pointer;
opt: Single): VstIntPtr; cdecl;
always returns 0, unless otherwise defined.
all string-pointers points to zero terminated strings.
e[ ]: = plugin receives as entry parameter
x[ ]: = plugin returns to host
The plugin calls the audioMasterCallback() function with the opcodes 00 thru 49:
0. audioMasterAutomate
>= VST1.0
@see AudioEffect::setParameterAutomated()
plugin notifies host that the plug has changed a parameter value thru its GUI or MIDI.
e[index]: parameter index
e[opt]: parameter value
x[return]: 0
1. audioMasterVersion
>= VST1.0
@see AudioEffect::getMasterVersion()
plugin requests host VST-specification version, currently 2 (0 for older)
x[return]: Host VST version (for example 2400 for VST2.4)
2. audioMasterCurrentId
>= VST1.0
@see AudioEffect::getCurrentUniqueId()
plugin requests host for current unique identifier
x[return]: current unique ID of a shell plug-in (in VST2.3 x[return]: the unique ID of the plug
that is currently loaded)
3. audioMasterIdle
>= VST1.0 @see AudioEffect::masterIdle()
plugin calls host idle routine (this will call effEditIdle for all open editors too)
has no arguments
4. audioMasterPinConnected
>= VST1.0 ... deprecated in VST2.4r2 @see AudioEffect::isInputConnected(), AudioEffect::isOutputConnected()
plugin inquires host if an input or output is being connected
e[index]: enumerates input or output counting from zero
e[value]: 0 = input, else = output
x[return]: the return value is 0 for <true> such that older versions will always return true.
// VstEvents + VstTimeInfo
5. unknown
>= VST2.0
not defined
6. audioMasterWantMidi
>= VST2.0 ... deprecated in VST2.4 @see void AudioEffectX::wantEvents()
(might need to be re-enabled to ensure 2.3/2.4 compatibility)
plugin (VSTi2.0 thru VSTi2.3) calls this to tell the host that the plugin is an instrument
e[value]: is a filter which is currently ignored
7. audioMasterGetTime
>= VST2.0
@see VstTimeInfoFlags, AudioEffectX::getTimeInfo()
e[value]: request mask, should contain a mask indicating which fields are required (see valid masks above),
as some items may require extensive conversions. For valid masks see VstTimeInfo.Flags
e[ptr]: returns VstTimeInfo* or null if not supported
8. audioMasterProcessEvents
>= VST2.0
@see VstEvents, AudioEffectX::sendVstEventsToHost()
plugin informs host that the plugin has MIDI events ready for the host to process
e[ptr]: pointer to VstEvents*
x[return]: 1 = supported and processed OK
9. audioMasterSetTime
>= VST2.0 ... deprecated in VST2.4 @see VstTimeInfoFlags, AudioEffectX::setTimeInfo()
e[value]: filter
e[ptr]: pointer to VstTimenfo*
10. audioMasterTempoAt
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::tempoAt()
( might need to be enabled to ensure 2.3/2.4 compatibility)
e[value]: sample frame location
x[return]: tempo (in bpm * 10000)
11. audioMasterGetNumAutomatableParameters
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::getNumAutomatableParameters()
plugin asks host number of automatable Parameters
x[return]: number of automatable Parameters (should be <= than numParams)
12. audioMasterGetParameterQuantization
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::getParameterQuantization()
e[value]: parameter index (-1: all, any)
x[return]: integer value for +1.0 representation, or 1 if full single float precision is maintained in automation.
// connections, configuration
13. audioMasterIOChanged
>= VST2.0
@see AudioEffectX::ioChanged()
plugin notifies host the numInputs and/or numOutputs of plugin has changed
x[return]: 1 = supported
14. audioMasterNeedIdle
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::needIdle()
plugin needs idle calls (outside its editor window)
has no arguments
15. audioMasterSizeWindow
>= VST2.0 (editor)
@see AudioEffectX::sizeWindow()
plugin requests host to resize the window of the plugin editor
e[index]: new width in pixels
e[value]: new height in pizels
x[return]: 1 = supported
16. audioMasterGetSampleRate
>= VST2.0
@see AudioEffectX::updateSampleRate()
x[return]: current sample rate
17. audioMasterGetBlockSize
>= VST2.0
@see AudioEffectX::updateBlockSize()
x[return]: current block size
18. audioMasterGetInputLatency
>= VST2.0
@see AudioEffectX::getInputLatency()
plugin requests input latency from host
x[return]: input latency in samples
19. audioMasterGetOutputLatency
>= VST2.0
@see AudioEffectX::getOutputLatency()
plugin requests output latency from host
x[return]: output latency in samples
20. audioMasterGetPreviousPlug
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::getPreviousPlug()
e[value]: input pin (-1: first to come),
x[ptr]: host returns pointer to cEffect*
21. audioMasterGetNextPlug
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::getNextPlug()
e[value]: output pin (-1: first to come),
x[ptr]: host returns pointer to cEffect*
22. audioMasterWillReplaceOrAccumulate
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::willProcessReplacing()
x[return]: 0 = not supported, 1 = replace, 2 = accumulate
23. audioMasterGetCurrentProcessLevel
>= VST2.0
@see AudioEffectX::getCurrentProcessLevel()
x[return]: currentProcessLevel
24. audioMasterGetAutomationState
>= VST2.0
@see AudioEffectX::getAutomationState()
x[return]: 0 = not supported, 1 = off, 2 = read, 3 = write, 4 = read/write
25. audioMasterOfflineStart
>= VST2.0
@see AudioEffectX::offlineStart()
e[index]: number of new audio files to start
e[value]: number of audio files to start
e[ptr]: pointer to *audioFiles
x[return]: 0 = error, 1 = OK
26. audioMasterOfflineRead
>= VST2.0
@see AudioEffectX::offlineRead()
e[index]: 1 = readSource
e[value]: option of type VstOfflineOption
e[ptr]: points to offline* offline structure, see below.
x[return]: 0 = error, 1 = OK
27. audioMasterOfflineWrite
>= VST2.0
@see AudioEffectX::offlineWrite()
e[index]: 1 = readSource
e[value]: option of type VstOfflineOption
e[ptr]: points to offline* offline structure, see below.
x[return]: 0 = error, 1 = OK
28. audioMasterOfflineGetCurrentPass
>= VST2.0
@see AudioEffectX::offlineGetCurrentPass()
x[return]: 0 = error, 1 = OK
29. audioMasterOfflineGetCurrentMetaPass
>= VST2.0
@see AudioEffectX::offlineGetCurrentMetaPass()
x[return]: 0 = error, 1 = OK
30. audioMasterSetOutputSampleRate
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::setOutputSamplerate()
for variable i/o
e[opt]: sample rate
31. audioMasterGetSpeakerArrangement
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::getOutputSpeakerArrangement()
x[return]: host returns a pointer to VstSpeakerArrangement* structure
32. audioMasterGetVendorString
>= VST2.0
@see AudioEffectX::getHostVendorString()
x[ptr]: host returns a pointer to a string identifying the vendor (max 64 char)
x[return]: 0 = error, 1 = OK
33. audioMasterGetProductString
>= VST2.0
@see AudioEffectX::getHostProductString()
x[ptr]: host returns a pointer to a string with product name (max 64 char)
x[return]: 0 = error, 1 = OK
34. audioMasterGetVendorVersion
>= VST2.0
@see AudioEffectX::getHostVendorVersion()
x[return]: vendor-specific version
35. audioMasterVendorSpecific
>= VST2.0
@see AudioEffectX::hostVendorSpecific()
no definition, vendor specific handling
x[return]: 0 = not supported
36. audioMasterSetIcon
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::setIcon()
e[ptr]: void*, format not defined yet
x[return]: 0 = error, 1 = OK
37. audioMasterCanDo
>= VST2.0
@see AudioEffectX::canHostDo()
plugin queries if host 'cando'
e[ptr]: string-pointer to cando string
x[returns]: 0 = No, 1='cando', 0='don't know' (default)
br>
38. audioMasterGetLanguage
>= VST2.0
@see AudioEffectX::getHostLanguage()
plugin queries what language is set for the host
x[returns]: see enum VstHostLanguage
39. audioMasterOpenWindow
>= VST2.0 ... deprecated in VST2.4 (editor) @see AudioEffectX::openWindow()
e[ptr]: pointer to window*
x[return]: host returns platform specific pointer*
40. audioMasterCloseWindow
>= VST2.0 ... deprecated in VST2.4 @see AudioEffectX::closeWindow()
close window,
e[ptr]: platform specific handle
41. audioMasterGetDirectory
>= VST2.0
@see AudioEffectX::getDirectory()
plugin requests host for plugin directory
x[ptr]: string-pointer to directory, FSSpec on MAC
42. audioMasterUpdateDisplay
>= VST2.0
@see AudioEffectX::updateDisplay()
Something has changed, update the host's 'multi-fx' display.
x[return]: 1 = supported
43. audioMasterBeginEdit
>= VST2.1 (editor)
@see AudioEffectX::beginEdit()
plugin calls this before a setParameterAutomated with mouse move (one per Mouse Down). It tells the host
that if it needs to, it has to record automation data for this control
e[index]: parameter index
x[return]: 1 = supported by host
44. audioMasterEndEdit
>= VST2.1 (editor)
@see AudioEffectX::endEdit()
plugin calls this after a setParameterAutomated (on Mouse Up). It notifies the host that this control is
no more moved by the mouse
e[index]: parameter index
x[return]: 1 = supported by host
45. audioMasterOpenFileSelector
>= VST2.1 (editor)
@see AudioEffectX::openFileSelector()
plugin requests: open a fileselector window
e[ptr]: pointer to VstFileSelect*
x[return]: 1 = supported by host
46. audioMasterCloseFileSelector
>= VST2.2 (editor)
@see AudioEffectX::closeFileSelector()
plugin requests: close a fileselector operation, must be always called after an openFileSelector !
e[ptr]: pointer to VstFileSelect*
x[return]: 1 = supported by host
47. audioMasterEditFile
>= VST2.2 ... deprecated in VST2.4 @see AudioEffectX::editFile()
open an editor for audio (defined by XML text in <ptr>)
e[ptr]: pointer to XML text
x[return]: 0 = error, 1 = OK
48. audioMasterGetChunkFile
>= VST2.2 ... deprecated in VST2.4 @see AudioEffectX::getChunkFile()
plugin requests the native path of currently loading bank or project (called from writeChunk)
x[ptr]: pointer to char[2048] or (MAC)sizeof(FSSpec)
x[return]: 0 = error, 1 = OK
49. audioMasterGetInputSpeakerArrangement
>= VST2.3 ... deprecated in VST2.4 @see AudioEffectX::getInputSpeakerArrangement()
x[return]: host returns a pointer to VstSpeakerArrangement* structure
__________________________________________________________________________________________________________
ONLY the following audioMaster callbacks are allowed before the initial DLL-call "main()" or
"VstPluginMain()" returns to host:
{01} audioMasterVersion
{06} audioMasterWantMidi ... deprecated in VST2.4
{32} audioMasterGetVendorString
{33} audioMasterGetProductString
{34} audioMasterGetVendorVersion
{38} audioMasterGetLanguage
{41} audioMasterGetDirectory
