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Name

mouseWheel()

Examples
void setup() {
  size(100, 100);
}

void draw() {} 

void mouseWheel(MouseEvent event) {
  float e = event.getCount();
  println(e);
}

Description The code within the mouseWheel() event function is run when the mouse wheel is moved. (Some mice don't have wheels and this function is only applicable with mice that have a wheel.) The getCount() function used within mouseWheel() returns positive values when the mouse wheel is rotated down (toward the user), and negative values for the other direction (up or away from the user). On OS X with "natural" scrolling enabled, the values are opposite.

Mouse and keyboard events only work when a program has draw(). Without draw(), the code is only run once and then stops listening for events.
Syntax
mouseWheel(event)
Parameters
event MouseEvent: the MouseEvent
Returnsvoid
RelatedmouseX
mouseY
pmouseX
pmouseY
mousePressed
mousePressed()
mouseReleased()
mouseClicked()
mouseMoved()
mouseDragged()
mouseButton
Updated on June 6, 2020 10:05:46pm EDT