Listener('mouseleave', function(e){
        draw_solver_2(0, 0, false);
    }, false);
}

function draw_solver_2(client_x, client_y, do_guides){
    var solver = document.getElementById("solver_2");
    var context = solver.getContext("2d");
    // background
    context.fillStyle="#eeeeee";
    context.fillRect(0, 0, w, h);

    // only lines now
    for(var i = 0; i < solver_1_eqs; ++i){
        var eq = eval("solver_1_eq_" + (i + 1));     
        // line
        context.beginPath();
        context.line