/* * _01_Red_Snake * * How to program a moving object leaving traces of the mouse movement on the screen. * * (c) 2013-2016 Arduino LLC. */ int red = 255; void setup() { size(400, 400); } void draw() { noStroke(); fill(red, 0, 0); ellipse(mouseX, mouseY, 30, 30); // Circle according to the mouse coordinates }