Game Lab Documentation

sprite.velocityX

Category:Sprites

Velocity in the positive x direction of the sprite in pixels per frame.

A positive value will move the sprite to the right, a negative value will move to the left. Must be used with the draw() {} function containing a drawSprites().

The default velocityX is 0. All sprite properties can be both accessed and updated.

Examples

Vibration

Make a sprite vibrate by alternating velocityX positive and negative.

// Make a sprite vibrate by alternating velocityX positive and negative.
var sprite = createSprite(200, 200);
sprite.velocityX = 5;
sprite.velocityY = 1;
function draw() {
  background("white");
  drawSprites();
  if (sprite.velocityX>0) {
    sprite.velocityX = -5;
  }
  else {
    sprite.velocityX = 5;
  }
}

var sprite = createSprite(200, 200);
sprite.velocityX = 1;
function draw() {
  background("white");
  drawSprites();
}

Syntax

sprite.velocityX

Returns

Velocity in the positive x direction.

Tips

velocityX can be used similarly to using the "counter pattern" on sprite.x within the draw() {} function.
Changing World.frameRate will affect the velocityX.
Sprites all have the same properties and you use the dot notation (combining the name of the sprite, followed by a dot, with the label of the property) to both access and update the property for that sprite.
Any changes to the properties of a sprite will not be seen until after drawSprites() is called.

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