How to use API creation? Summary of API creation instance usage

You can create many applications using the Canvas API: graphics, charts, and picture editing. One of the most wonderful applications is to modify or overwrite existing content. The most popular overlay map is called a heat map. Heat maps can be used on city maps to mark traffic conditions or to show storm activity. On the map, you only need to overlay the canvas on the map and display it. It actually uses canvas to cover the map, and then draws different heat levels based on the corresponding activity data. An example is provided below.