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LoadProgress

The properties of the LoadProgress class can be used to monitor the progress when loading elements of VST presets.

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LoadProgress Class

Classes

LoadProgress Class

Description

The functions loadPresetAsync, appendLayerAsync and insertLayerAsync return a LoadProgress object. The properties of the LoadProgress object are described by the following fields.

Available in: Controller.

Fields

Field	Description	Value Type
.progress	The load progress in the range from 0 to 1.	number
.root	The value of `.root` will be the Element object of the first element (root) of the loaded VST preset. Depending on whether you load a layer, program, or multi-program VST preset, this is either an Element object of the type Layer, Program,or Instance.	Layer, Program, or Instance
.cancel	Set this to true to cancel the loading of the preset.	boolean
.error	Message if an error occured.	string
.info	User definable field, for example, to manage several loading threads.	string or table

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