Crate game_time [−] [src]
Time handling for games and other real-time simulations.
Provides types and helpers for dealing with time in games. game_time
allows for
easy decoupling of internal "game" time and external "wall" time, as well as tracking
frame rate.
Additionally, different kinds of time steps may be used, while also setting a multiplier for speeding up/slowing down game time progression.
Usage
Put this in your Cargo.toml
:
[dependencies]
game_time = "0.2.0"
Overview
game_time
consists of 4 main types.
GameClock
provides the basic time keeping for a simulation, tracking frames and returning aGameTime
at the beginning of each.GameTime
provides the time information for each frame.FrameCount
objects can be optionally used to track frame rate and other runtime statistics, utilizing swappable methods for computing the average fps.FrameRunner
combines aGameClock
andFrameCount
and makes it easy to run the simulation at a given frame rate.
For each frame, a TimeStep
is passed to GameClock
in order
to advance the frame. This allows the frame rate to be changed at any time, and allows different
kinds of time steps (fixed, variable and a constant step are supported by default) to be used
based on what is most useful. Together, these objects combine to form a convenient but
flexible framework for time progression.
Examples
Run a simulation with 50ms frames, without fps counting:
use game_time::GameClock; use game_time::step; use game_time::FloatDuration; let mut clock = GameClock::new(); let end_time = FloatDuration::seconds(10.0); let mut sim_time = clock.last_frame_time().clone(); let step = step::ConstantStep::new(FloatDuration::milliseconds(50.0)); while sim_time.total_game_time() < end_time { sim_time = clock.tick(&step); println!("Frame #{} at time={:?}", sim_time.frame_number(), sim_time.total_game_time()); }
Run a simulation at 30fps, sleeping if necessary to maintain the framerate:
use game_time::{GameClock, FrameCounter, FrameCount, FloatDuration}; use game_time::framerate::RunningAverageSampler; use game_time::step; let mut clock = GameClock::new(); let mut counter = FrameCounter::new(30.0, RunningAverageSampler::with_max_samples(60)); let end_time = FloatDuration::seconds(10.0); let mut sim_time = clock.last_frame_time().clone(); while sim_time.total_game_time() < end_time { sim_time = clock.tick(&step::FixedStep::new(&counter)); counter.tick(&sim_time); println!("Frame #{} at time={:?}", sim_time.frame_number(), sim_time.total_game_time()); }
Reexports
pub use self::clock::GameTime; |
pub use self::clock::GameClock; |
pub use self::framerate::FrameCounter; |
pub use self::framerate::FrameCount; |
pub use self::framerate::FrameRateSampler; |
pub use self::runner::FrameRunner; |
pub use self::step::TimeStep; |
Modules
clock |
Types for counting and recording time in a simulation. |
framerate |
Utilities for frame rate computation and management. |
runner |
Implements the |
step |
Types for computing game time from wall time. |
Structs
FloatDuration |
A time duration stored as a floating point quantity. |