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loadPresetAsync

loadPresetAsync(path, callback)

Description

Function to load the elements of a VST preset in a separate, parallel thread. Loading the VST preset in a separate thread can be necessary if the preset is too big to be loaded in a short time. The function returns a LoadProgress object that can be used to get information on the load progress and the loaded elements, for example. After the preset is loaded, the callback function is called. The callback function gets the LoadProgress object as default argument.

Available in: Controller.

Arguments

Return Values

Returns a LoadProgress object.

Example

-- Start with an empty program, remove any existing layers.

layers = this.parent:findLayers()
 
if layers then
   for i, layer in ipairs(layers) do
       this.parent:removeLayer(layer)
   end
end
 
-- Table with layer presets from Skylab.
layerPresets = {
   { name = "Ambient Pad 01", path = "vstsound://724ACB205EFF46F885735D1B216C37AD/.AppData/Steinberg/Skylab/Sub Presets/Layer Presets/Ambient Pads/Ambient Pad 01.vstpreset" },
   { name = "Ambient Pad 02", path = "vstsound://724ACB205EFF46F885735D1B216C37AD/.AppData/Steinberg/Skylab/Sub Presets/Layer Presets/Ambient Pads/Ambient Pad 02.vstpreset" },
   { name = "Ambient Pad 03", path = "vstsound://724ACB205EFF46F885735D1B216C37AD/.AppData/Steinberg/Skylab/Sub Presets/Layer Presets/Ambient Pads/Ambient Pad 03.vstpreset" },
   { name = "Ambient Pad 04", path = "vstsound://724ACB205EFF46F885735D1B216C37AD/.AppData/Steinberg/Skylab/Sub Presets/Layer Presets/Ambient Pads/Ambient Pad 04.vstpreset" },
}
-- Create a table with the preset names.
function getPresetNames()
   presetNames = {}
   for i, preset in ipairs(layerPresets) do
       presetNames[i] = preset.name
   end
end
 
getPresetNames()
 
-- Remove the old layer after the new one was added.
function removeOldLayer(progressInfo)
   local newPreset = progressInfo.root
   if oldPreset then
       this.parent:removeLayer(oldPreset)
       print(oldPreset.name.." removed.")
   end
   oldPreset = newPreset
end
 
-- Append the preset in a separate thread.
function appendNewLayer(progressInfo)
   if progressInfo.root then
       this.parent:appendLayerAsync(progressInfo.root, removeOldLayer)
       print("Appending "..progressInfo.root.name.."...")
   end
end
 
-- Load the preset in a separate thread.
function onSelectPresetChanged()
   progress = 0
   progressInf = loadPresetAsync(layerPresets[SelectPreset].path, appendNewLayer)
   print("Loading "..layerPresets[SelectPreset].name.."...")
end
 
-- Define a parameter for selecting the preset to be loaded.
defineParameter("SelectPreset", "Select Preset", 1, presetNames, onSelectPresetChanged)
 
-- Monitor the load progress with onIdle.
progress = 1
function onIdle()
   if progress < 1 then
       progress = progressInf.progress
       print("Progress: "..(progressInf.progress * 100).."%")
   end
end

See also: loadPreset, LoadProgress