In this lesson, we will talk about components, how to add them, why we need them, you will get to know two important physics components, collider and rigid body. Finally, we will learn physics materials, which help us to set bounciness and friction. As you already know, all objects are empty game objects with different components, how to add components that click on our object and click here Add Component you should understand that there are actually two separate physics engines in unity, one for 3d physics and one for 2d physics. For example, there is a collider component 2d phase just you know plain Plain object, and for 3d it's like a cube. Right now we work. We work on our 2d games.

So we will use 2d colliders. So the basic components are physics ones, because if we right now, click on Play nothing is happening. So I accidentally plane mode and we need to add a Collider. So Add Component and circle collider from my circle. collider components define the shape of an object for the purposes of physical collisions. A Collider, which is invisible, does not need to be the same shape as the game objects match.

There are simplest colliders, box circle and compound colliders. So, we have added the circle one due to this green circle around our object. This is it. Now we can click on Edit collider here and make it smaller or bigger. All right, let's go ahead and add a collider for our ground. Again, Add Component.

This time it has a box Collider. And you see maybe it is too big for our ground. Let's click on Edit collider like this out Okay, ready, good. Now the game objects have physical shapes and can participate in physics events, but they can't initiate them. They don't react to physics forces and is not influenced by gravity. So we still don't see any differences in plane mode.

So we need another component, rigid body. I select my circle at component, region rigidbody 2d. Alright. rigid bodies enable game objects to act under the control of physics. So, I just added to that rigidbody 2d to my circle and if I am to the plane mode. I will see that Yeah, my circle is that my circle is falling down.

Again, boom. Do it again. Boom. Alright, so it has fallen down because of gravity. And if I uncheck the collider that game object will simply pass through our ground because it doesn't have a physical shape. You can also add physics material to object.

So we can about 2d object. That physics material helps you to add bounciness and friction. Go to the Project panel and click on Create physics material 2d and let's rename it to bouncing All right. And you see there are two parameters here, friction and bounciness. Let's set bounciness to one. All right, and click on my circle, find my Collider.

Let's check it. And you see this material here. Now material slot, you can simply drag and drop our physics, physics material here. Alright, let's see. Boom, yay. Yeah, this this is the bounciness.

That's right. All right. Now the objects not only react to the physics forces and other colliders, but it also done it in a ballsy manner, which was great. locate our ball by clicking Ctrl D. All right, let's move it a little bit and change its position. Both circles, huh? Okay, now select the second one.

And let's take a look at the rigidbody. So we have mass here, that is the weight of our object. And also we have gravity scale. So if your game needs a normal gravity, for example, like on other planets, maybe you can adjust gravity here. Let's, for example, type something like five. So, you see, this is the ball.

This is the circle. Now if you look and now it looks like More like a mall. Well anyway, it is the object with normal gravity and this is with a normal. One more thing about rigid body is body type. Here there are three options for body type, each defines a common and fixed behavior and dynamic rigid body to the is designed to move under a simulation and static, rigid body is designed to not move under simulation at all. And kinematic rigidbody 2d is designed to move under simulation but only under strong user control.

So, while and dynamic rigid body is affected by gravity and horses, that kinematic rigid body Doesn't. So if we need, for example, rigid body for our ground and if we don't change its body type. So let's see what will happen. Yeah, our ground is falling down because of gravity. So all we need to do is just set that up here. And right now it doesn't move doesn't fall, which is great.

And so let's go back to our bouncy physics material. And let's say you need a slippery object. So for example, that may make our ground slippery, I will use the same material that the friction to zero and bounciness to zero and rotated a little bit to that common ground rotated. And don't forget to drag and drop our bouncy here. And let's check that our circles don't have it. Okay, good.

So no friction means slippery. So that means that our ground is slippery now like ice. For example, if your platforms made for ice, it can work for you. Each unity component has the little blue book over here. And if you click here, you open unity manual and can get all the information about this component. So unity documentation can be very, very useful and I encourage you to read it from time to time but To be honest, I don't need to encourage you because you need to read this documentation.

So now you know how to work with components, how and why to add them, add them and even know the most important physics components.