normalscale scale interpolate

gistfile1.txt

Math.normalscale = function(minv, maxv, lst)
{
    for (var n = 0; n < lst.length; ++n)
    {
        var k = (Math.abs(maxv - minv) > 0.001) ? ((lst[n] - minv) / (maxv - minv)) : 0;
        lst[n] = 1-k;
    }
};

Math.scale = function(width, height, maxdim)
{
    var scale = Math.min(maxdim / width, maxdim / height);
    return [scale * width, scale * height];
};

//alpha == 255, then all weight is val1, if alpha is 0, then all weight is val2
Math.interpolate = function(alpha, val1, val2)
{
    return ((val1 + 1) * alpha >> 8) - ((val2 + 1) * alpha >> 8) + val2;
};