awoo

Animate and schedule code.

This crate provides a very simple mechanism to animate some code. Consider:

``` let mut time = 0.; // time that passes let a = 0.; let b = 1.; let c = 2.;

// main loop of our application loop { if time < a { // do something until time passes a point in time a } else if time < b { // do something until time passes a point in time b } else if time < c { // do something until time passes a point in time c } // etc. etc.

// time advances here time += 0.1;

if time >= c { break } } ```

That might sound surprising to you, but a lot of demoscene productions are written with that kind of if / else if blocks. It’s pretty bad and ugly though, I agree. For several reasons:

• It doesn’t compose at all. If you want to do something in between α and β, you will have to break the whole block and change every timings.
• Dynamic branching will get worse and worse as time passes, since you’re going to make more and more tests.
• The code is just ugly!

Instead of writing that kind of code, we can do better:

``` use awoo::window::Window;

let prealpha = Window::new(0., 1.); // do something until time passes 1. let prebeta = Window::new(1., 2.); // do something until time passes 2. let pre_gamma = Window::new(2., 3.); // do something until time passes 3. ```

By default, [Window<T>] is just a window of time T. We can map actions to completely do the same thing as above:

let pre_alpha = Window::new(0., 1.).map(|time| println!("time is {}", time));

The type of that [MappedWindow<_>] is determined by what you return from your closure in the map call. Once all windows are created, you can schedule them:

``` use awoo::scheduler::RandomAccessScheduler; use awoo::time::simple::SimpleF32TimeGenerator;

let mut scheduler = RandomAccessScheduler::new( SimpleF32TimeGenerator::new(0., 0.1), // a generator that generates linear time starting at 0 and incrementing by 0.1 vec![prealpha, prebeta, pre_gamma] // our mapped windows ).unwrap();

scheduler.schedule(); ```

What’s interesting is that we can get the windows from a file, for instance, and map them on the fly.