private TextureSet randomTextureSetFromDayNumber(int dayNumber)
{
// 4 texture sets, add a new one into the mix every 10 days -- hence the mod 41 here
// (41 instead of 40, as day isn't zero indexed -- it begins at 1!)
int dayNumWithinBounds = dayNumber % 41;
if (dayNumWithinBounds <= 10)
{
// just normal
return(TextureSet.Normal);
}
else if (dayNumWithinBounds <= 20)
{
// add kanji in
return(RandUtil.From(TextureSet.Normal, TextureSet.Kanji));
}
else if (dayNumWithinBounds <= 30)
{
// add downer in
return(RandUtil.From(TextureSet.Normal, TextureSet.Kanji, TextureSet.Downer));
}
else if (dayNumWithinBounds <= 40)
{
// full choice!
return(RandUtil.RandomEnum <TextureSet>());
}
// TODO: randomly introduce the glitch texture set
// shouldn't get here due to the mod 41, but we need a default return otherwise C# will moan!
return(TextureSet.Normal);
}