smooth-scroll-js

Smooth Scroll with mouse JS The code you provided is a JavaScript implementation of smooth scrolling functionality. It allows for smooth scrolling when the user scrolls using the mouse wheel or trackpad.

Here's a breakdown of how the code works:

1. The init() function is called when the window's DOM content is loaded. It initializes the smooth scrolling by creating a new instance of the SmoothScroll class.

2. The SmoothScroll constructor function takes three parameters: target, speed, and smooth. The target parameter represents the element to which the smooth scrolling should be applied. The speed parameter determines the scrolling speed, and the smooth parameter controls the smoothness of the scrolling.

3. Inside the SmoothScroll constructor, the target element is determined. If the target is set to document, it is replaced with a cross-browser compatible scrolling element.

4. Event listeners are added to the target element for both the 'mousewheel' and 'DOMMouseScroll' events. The scrolled function is called when these events occur.

5. The scrolled function is responsible for handling the scroll events. It first prevents the default scrolling behavior. Then, it normalizes the scrolling delta value based on the browser type.

6. The pos variable keeps track of the current scroll position of the target element.

7. The scroll position is updated based on the scrolling delta and the scrolling speed. The new scroll position is limited to stay within the scrollable range of the target element.

8. The update function is called to animate the scrolling. It calculates the distance to scroll (delta) and gradually updates the target element's scrollTop property to move towards the desired scroll position.

9. The requestFrame function is a cross-browser compatibility fix for the requestAnimationFrame method. It ensures that the update function is called at the optimal time for smooth animation.

10. Finally, an event listener is added to the window object for the 'DOMContentLoaded' event. When the DOM content is loaded, the init function is called to initialize the smooth scrolling functionality.

Overall, this code provides a smooth scrolling experience when the user interacts with the mouse wheel or trackpad.