My actor jumps across the screen

It compiled and it is still wrong

My actor jumps across the screen

This page is part of Intro to Java with Greenfoot. It assumes you have reached lesson 3.5. Opening it is not counted against you and is not tracked as progress.

What it actually means

move counts CELLS, not pixels, so a large cell size turns a small move into a big jump.

The usual causes

Ranked by how often each one turns out to be the answer. Work down the list.

  1. The world has a large cell size, so each cell is many pixels on screen.
  2. The move distance is simply too large for the size of the world.
  3. setLocation is being given pixel values where cell coordinates were expected.

How to fix it

Look at the third number in your super call. If it is large, either reduce the move distance to suit or rebuild the world with a cell size of 1 for smooth movement. Grid games want big cells; action games want a cell size of 1.

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