10.6

208Logic Pro Effects
Tutorial script 5: Velocity Slider
Text following /* shows comments that explain the JavaScript code.
function HandleMIDI(event) {
event.velocity = GetParameter("Note Velocity");
/* retrieves "Note Velocity" information from the defined "Note Velocity"
parameter */
event.send(); /* sends the note event */
}
var PluginParameters = [{name:"Note Velocity", type:"lin", minValue:1,
maxValue:127, numberOfSteps:126, defaultValue:80"}];
/* create a linear parameter called "Note Velocity" with a range of 1 to
127, and a default value of 80 */
Logic Pro Scripter MIDI plug-in SetParameter function
The SetParameter() function allows you to programmatically set the value of a control.
Usage is similar to the Logic Pro Scripter MIDI plug-in GetParameter function, but you need
to add a second argument for the value you want to set.
• The first argument describes which parameter is accessed. This can be either an integer
(index) or a string (parameter name).
• The second argument is the value that you want to set (this is always a number).
Important: Using SetParameter and track automation for a parameter at the same time can
lead to unexpected behavior. You can circumvent such problems by disabling automation
for each parameter.
Code use example
The example code creates a slider control and resets the value of that slider to 0 each time
the plug-in is reset.
Note: You can opt out of automation on a per-parameter basis by including
'disableAutomation:true' in the parameter definition.
function Reset() {
SetParameter('slider', 0);}
var PluginParameters = [{name:'slider', type:'lin', defaultValue:0.5,
numberOfSteps:100, minValue:0, maxValue:1}];