Hi,

sorry if this a dumb question, just starting out in XNA :)

I'm trying to do 3D clock by using SpriteFont,but can't make drop shadow effect nicely.

I have seen some examples in XNA 2.0 book which I didn't buy ( was for real beginers  ) and author
did achieve this effect somehow buy using Alpha channel, but I don't remember how he did it.

I think I'm missing something as in my case shadow is simply black..

This is how I'm trying to draw shadow:

1. // draw shadow by using alpha = 20 
2.             for (int i = 0; i < 3; i++)
3.             {
4.                 pos.Y -= 1;
5.                 pos.X -= 1;
6.  
7.                 spriteBatch.DrawString(myFont, sTime, pos, new Color(new Vector4(0, 0, 0, 20)), 0, Vector2.Zero, 1, SpriteEffects.None, 0);
8.             }

Code link http://pastebin.com/m7e71eba1

When you call SpriteBatch begin you must specify a SpriteBlendMode to enable alpha blending. Your two choices are additive blending using SpriteBlendMode.Additive or alpha blending using SpriteBlendMode.Alpha.

Also, when you use the Vector4 overload of Color's constructor, valid values are 0.0-1.0

thanks guys for super quick replays! :)

Problem was because values for Vector4 has to be between 0.0 - 1.0 as you've said.