function increaseOpacity (obj) {
    obj.style.opacity = 1.0;
}

function decreaseOpacity (obj) {
    obj.style.opacity = 0.6;
}

var counter = 0;
var opacity = 1.0;
var numimg = 0;
var factor = 0.002; // 0.005;
var anime = true;
var lowLimit = 0.5;  //63

function pause() {
    opacity = 1.0;
    factor = 0.002;
    anime = false;
    devImg().style.opacity = 1.0;
}

function swap() {
    //var otherImg = new Image();
    if (numimg == 0) {
	numimg = 1;
	devImg().src = "images/dev/jsportal.png";
    }
    else {
	numimg = 0;
	devImg().src = "images/dev/gemhunt.png";
    }
    devImg().style.opacity = opacity;

    lowLimit = 0.5;
    counter = 0;
}

function flyin(img) {
    img.style.position.left++;
}

var steps = -1000;
var speed = 300;
var opa = 1.0;

function runEffects() {

    var img01 = document.getElementById("img01");
    var img02 = document.getElementById("img02");

    if (steps < 0) {
	img02.style.left = steps + "px";
	img01.style.left = steps + "px";
	steps += speed;
	if (speed > 2) {
	    speed = speed / 1.46; //2.07
	}
    }
    else if  (opa > 0.5) {
	img01.style.opacity = opa;
	img02.style.opacity = opa;
	opa -= 0.01;	    
    }

    if (!anime) return;


    if (opacity < lowLimit && factor > 0) {
	opacity = lowLimit;
	factor *= -1;
	counter++;
	if (counter == 3) {
	    lowLimit = 0.01;	    
	}
	if (opacity <= 0.01) {
	    swap();
	}
    }
    if (opacity >= 1.0) {
	opacity = 0.99;
	factor *= -1;
    }
    opacity -= factor;
    devImg().style.opacity = opacity;
    
}

function devImg() {
    return document.getElementById("devimg");
}