Drawing distorted polylines and polygons

[javc86]

Hi @dat-ng actually I have a problem when I want to draw a polyline or a polygon on canvas. I made the calculates like you made in your project, but for my case I want to draw polylines and poligons like google maps. The issue is that I draw some them, they don't have the correct align. It's look like a error's margin on the calculate but I don't have any idea how I can correct it. Could you have some solution for this?

Here a screenshot with my app to the right and a page where I get the exact coordinates to the left.