Multithreading in XNA game

Where can I use multithreading in a s开发者_JAVA技巧imple 2D XNA game? Any suggestions would be appreciated

Well, there are many options -

Most games use mutlithreading for things such as:

1. Physics
2. Networking
3. Resource Loading
4. AI/Logical updates (if you have a lot of computation in the "update" phase of your game)

You really have to think about your specific game architecture, and decide where you'd benefit the most from using multithreading.

Some games use multithreaded renderers as a core design philosophy.

For instance... thread 1 calculates all of the game logic, then sends this information to thread 2. Thread 2 precalculates a display list and passes this to the GPU. Thread 1 ends up running 2 frames behind the GPU, thread 2 runs one frame behind the GPU.

The advantage is really that you can in theory do twice as much work in a frame. Skinning can be done on the CPU and can become "free" in terms of CPU and GPU time. It does require double buffering a large amount of data and careful construction of your engine flow so that all threads stall when (and only when) necessary.

Aside from this, a pretty common technique these days is to have a number of "worker threads" running. Tasks with a common interface can be added to a shared (threadsafe) queue and executed by the worker threads. The main game thread then adds these tasks to the queue before the results are needed and continues with other processing. When the results are eventually required, the main thread has the ability to stall until the worker threads have finished processing all of the required tasks.

For instance, an expensive for loop can be changed to used tasks.

// Single threaded method.
for (i = 0; i < numExpensiveThings; i++)
{
  ProcessExpensiveThings (expensiveThings[i]);
}

// Accomplishes the same work, using N worker threads.
for (i = 0; i < numExpensiveThings; i++)
{
  AddTask (ProcessExpensiveThingsTask, i);
}
WaitForAll (ProcessExpensiveThingsTask);

You can do this whenever you're guaranteed that ProcessExpensiveThings() is thread-safe with respect to other calls. If you have 80 things at 1ms each and 8 worker threads, you've saved yourself roughly 70ms. (Well, not really, but it's a good hand-wavy approximation.)

There is lots of place to apply to: AI, objects interaction, multiplayer gaming etc. This depends on your concrete game.

Why do you want to use multi-threading?

If it is for practice, a reasonable and easy module to put in its own thread would be the sound system, as communication is primarily one-way.

Multi-threading with GameComponents is meant to be quite straightforward e.g.

http://roecode.wordpress.com/2008/02/01/xna-framework-gameengine-development-part-8-multi-threading-gamecomponents/