Placing a tank on a planet
As part of his Procedural Planets series, Dave takes a break from generating and rendering a planet and instead tried to place a tank on the surface of the generated planet. Read about the whole implementation process on his blog.
More 2D collisions
After Glenn's Rotated Per Pixel Collision, George "good MVP that everyone likes" Clingerman just released a new sample that shows how to use the Separating Axis Theorem to implement 2D Rotated Rectangle Collision. Read all about it on his site.
Rotated Per Pixel Collision
Fellow MVP Glenn shares a method for checking collisions at pixel level on rotated sprites. You can see his code here.
Article : Spatial hashing implementation for fast 2D collisions
by Conkerjo
This article describes how to use a spatial hashing implementation to speed up collisions in your games.
This is a sample prototype I wrote to fix a performance limitation with collision checking in my game.
So what is spatial hashing? Here is a good 1 liner I will borrow from the source material i used.