Merge pull request #3 from Kerosene2000/master

Improved documentation

src/lib.rs

@@ -1,14 +1,23 @@
-//! This library implements Robert Penner's easing functions
-//! Easing functions calculate rate of change of a property over time
+//! This library implements Robert Penner's easing functions.
+//! Easing functions calculate rate of change of a property over time.
+//!
+//! A little website [easings.net](http://easings.net) can help visualising
+//! functions. Another can help you understanding Easing functions in details
+//! [upshots.org/jsas-understanding-easing](http://upshots.org/actionscript/jsas-understanding-easing).
+//!
+//! - **`t`** is the current time (or position) of the tween.
+//! This can be seconds or frames, steps, seconds, ms, whatever
+//! as long as the unit is the same as is used for the total time.
+//! - **`b`** is the beginning value of the property.
+//! - **`c`** is the change between the beginning and destination value of the property.
+//! - **`d`** is the total time of the tween.
 //!
 //! #example
 //!
-//! ```no_run
+//! ```
 //! use easer::functions::*;
-//! let mut x: [f32; 100] = [0.0; 100];
 //! let mut y: [f32; 100] = [0.0; 100];
 //! for i in 0..100 {
-//!     x[i] = i as f32;
 //!     y[i] = i as f32;
 //! }
 //! println!("Before {:?}", &y[..]);