SDL » SDL1 » Time
Proper time handling can make your game look more realistic, support other hardware better, and optimise resource usage.
When it comes to time, it pays to understand the different notions of time in your application. First, there's the user's (real) time. Then there's the CPU time. SDL keeps its own clock, started when it is initialized. Your game may also have a sense of time (independent from SDL's or the CPU's; the game clock may be paused).
Knowing about these differences helps understand that we need to be able to deal with the computer's time, and with one or more abstract notions of time (eg. your game might show time-driven animations while the action is paused). In the first part of this chapter we will deal with SDL's time facilities. In the second part, we will deal with game aspects that are time-related, such as pausing the game, basic physics and animating characters. See Game Programming Concepts for more advanced and detailed uses of time.
SDL provides a cross-platform clock with millisecond precision. The timer API only provides five functions: one to get the time, one to actively delay the current thread, and three to install future call-backs.
Dealing with callbacks tends to make your code harder to understand, so we will only introduce the main two functions.
Detecting the current time is essential to provide realistic animations and physics.
PLACE FOR "A VISUAL EXAMPLE
