I want to prototype an idea for a game I have. The idea for this game is that the player will dig through the ground, creating tunnels and finding treasure.
I\'m looking
There's some nice code at the bottom of the this thread. Also, this is a great step-by-step tutorial on achieving a destructible terrain.
EDIT - The original link for the second tutorial was broken, so I've linked to an archived version of it.
Here are two examples that build on each other of how to do this with pixel shaders in XNA 4. Both examples include sourecode.
http://www.syntaxwarriors.com/2012/xna-alpha-mapping-with-pixel-shaders/
http://www.syntaxwarriors.com/2012/xna-alpha-mapping-with-pixel-shader-and-rendertarget2d/
Doing this with pixel shaders is very fast as all the heavy lifting is done on the gpu.
Riemer has a similar approach to a game he developed in XNA, cannon shells cause the terrain to be "destroyed" and any props that were previously on said terrain are moved accordingly.
It needs to be refactored and improved for your needs but it's a start.
Riemer has a good selection of tutorials for other things too.
http://www.riemers.net/eng/Tutorials/XNA/Csharp/Series2D/Adding_craters.php
There are two possibilties, eighter one work, but it depends on XNA how easy it is to implement: