Perspective projection

Have you ever drawn a picture of a scene and made the things in the distance look smaller than the ones at the front? That is called perspective. Imagine looking at a street with different buildings. The buildings that are further away look smaller than the ones closer to you.

So, when we take a picture or create a 3D model of something, we need to have a way to show that distance and make everything look real. This is where perspective projection comes in.

Perspective projection is a way of showing a 3D object or scene on a flat surface, like a piece of paper or a computer screen. This technique mimics the way our eyes see the world by making objects that are further away appear smaller.

To do this, we use a special type of camera called a perspective camera or employ algorithms that perform perspective calculations. When we take a picture with a perspective camera, the camera lens captures the rays of light that reflect off the objects in the scene, all converging at a single point called the camera's center. This creates an image that mimics the natural way our eyes see the world.

When working with 3D models on a computer, we use perspective projection algorithms to calculate the position and size of objects in the scene. The computer simulates the process of light rays converging at a single point and projects a 2D image of the scene onto a flat surface.

In summary, perspective projection is a way of making a 3D object or scene look realistic on a flat surface by mimicking the way our eyes see the world. It makes objects that are further away appear smaller, just like they do in real life.