La mouse se déplace

function drawShape(){
        var lastX = 0, lastY = 0, count = 0;
        var r = Math.floor(Math.random()*255)+70;
        var g = Math.floor(Math.random()*255)+70;
        var b = Math.floor(Math.random()*255)+70;

        timer1 = setInterval(drawLoop, 16);
        
        function drawLines(x, y) 
        {
        ctx.lineWidth = 40;
        ctx.lineCap = "round";
        ctx.beginPath();
        ctx.moveTo(lastX, lastY);
        ctx.lineTo(x, y);
        ctx.strokeStyle = "rgba(" + r + "," + g + "," + b + ", 1)";
        ctx.stroke();
        }

        function drawLoop() 
        {
        // Clear first
        ctx.fillStyle = "rgba(0,0,0,0.05)";
        ctx.fillRect(0, 0, WIDTH, HEIGHT);
        
        // Draw lines
        drawLines(currentX, currentY);
        
        // Change up color
        if (count++ > 50) 
                                                {
                                                count = 0;
                                                r = Math.floor(Math.random() * 255) + 70;
                                                g = Math.floor(Math.random() * 255) + 70;
                                                b = Math.floor(Math.random() * 255) + 70;
                                                }
                                                
                                                // Update coordinates 
                                                lastX = currentX;
                                                lastY = currentY;
                                                }