AC system

ac.gml

function ac(_curve, _channel, _step, _backwards = false, _frame = 0, _disabled = false, _mn = 0, _mx = 1, _autoreset = true, _autodisable = true) constructor {
    curve       = _curve;
    channel     = _channel;
    step        = _step;
    backwards   = _backwards;
    frame       = _frame;
    disabled    = _disabled;
    mn          = _mn;
    mx          = _mx;
    autoreset   = _autoreset;
    autodisable = _autodisable;
    
    static update = function() {
        if(!disabled) {
            if(!backwards)
                frame = clamp(frame + step, mn, mx);
            else
                frame = clamp(frame - step, mn, mx);
        }
        if(frame == 0) {
            if(autoreset)   backwards = false;
            if(autodisable) disabled = true;
        }
		
		value = animcurve_channel_evaluate(animcurve_get_channel(curve, channel), frame);
    }
    
    static reset = function(maximum = false) {
        if(!maximum) frame = mn;
        else         frame = mx;
    }
}

function ac_updateall(arr) {
    for(var i = 0; i < array_length(arr); i++){
        arr[i].update();
    }
}