Call a JavaScript preload() function?

Question

If I check a radio button for the first time I'm getting a short freezing. Checking them a second time everything runs super smooth. I think because they are now in the browser-cache. Any chance of a preload here?

var insideMap1 = THREE.ImageUtils.loadTexture( 'insideMap1.jpg' );
var insideMap2 = THREE.ImageUtils.loadTexture( 'insideMap2.jpg' );
var insideMap3 = THREE.ImageUtils.loadTexture( 'insideMap3.jpg' );

$("input[name='opt1']").change(function() {

    if ($("#radio1").is(":checked")) {
        material[ "inside" ].map = insideMap1;
    }

    if ($("#radio2").is(":checked")) {
       material[ "inside" ].map = insideMap2;
    }

    if ($("#radio3").is(":checked")) {
       material[ "inside" ].map = insideMap3;
    }

});

Answer 1

Use THREE.Cache:

<script>
    $(document).ready(function() {

        THREE.Cache.enabled = true;

        var url = '/img/DSC03537.JPG';
        var newImg = document.createElement('img');
        newImg.src = url;
        THREE.Cache.add(url, newImg);

        // main program part
        var insideMap2 = THREE.ImageUtils.loadTexture(url);

        $("#testBox").change(function () {
                $("#tstImg").map = insideMap2;
        });
    });
</script>

Notice: THREE.ImageUtils.loadTexture is being deprecated. Use THREE.TextureLoader() instead.