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Skip to 0 minutes and 20 seconds So, in the previous video I was showing you how to fill the scene with different 3D objects. Now that we have the 3D objects, you see that even that the objects look nice, the scene doesn’t look very realistic, and this is because when we have 3D environments we need to simulate the behaviour of the light, but because the behaviour of the light is very complex, we don’t have the power on our machines to make very very complex realistic simulation of the light that runs on real time.

Skip to 0 minutes and 49 seconds So, because of that, all the 3D engines that we use with our 3D environments, they tend to have very simplistic lighting simulation and, because of that, usually what we see on the screen is not as realistic as we want. Anyway, in this scene right now we can see that the light is coming from this direction. This is because here we have this object that is our light source. So I’m going to click it and I’m going to drag it around, so you can see that when we move the light how the shading of the objects changes. As you can see if you pay attention, there’s no shadows right now.

Skip to 1 minute and 22 seconds Shadows is a very complex thing that you will need to fine-tune if you want to have them. Right now we are going to forget about the shadows. So, we have this light here. When you work in a 3D environment there’s lot of different kinds of lights, but there are three very basic lights that you will find in all the 3D softwares. In this case, the light for instance, this kind of light is called Omni light, and it’s called Omni light because the light is being emitted in every direction, so it doesn’t matter where the light is. light goes in every single direction.

Skip to 1 minute and 54 seconds But if we want to have something more like a Spot light, we can change here here I’m going to change to “Spot”. So this is a Spot light. As you can see when I move the light around, it’s only emitting light in this direction. Usually the spotlights in all the 3D engines they have this property to change how much the area that is inside the penumbra, the angle of the area in the penumbra and also how big is the whole cone of the light. This is usually used when you want to create more like a dramatic effect. There is also a third kind of light that you will find in all engines which is called the Directional light.

Skip to 2 minutes and 35 seconds The Directional light is the light that comes, every single ray comes from in parallel to this plane. It’s usually used for outside lights, like if you want to simulate the behaviour of the sun, so you have light it doesn’t matter what is the light, the only important thing is the direction of the light, so you can see, maybe you will see better like if I have a Spot light here and I move around the light, you will see that the area that is in the centre, because it’s pointing to the light, gets more light, but if I switch it to Directional, you will see that there is more light coming to this object.

Skip to 3 minutes and 17 seconds Anyway, it’s important to play around with the lights when you want to have a more realistic look, like in this case, for instance, this area here doesn’t have any light, maybe it will look kind of flat, so you don’t want to look very flat, what you can do is add more lights to the scene. But remember, the more light the scene has, the performance is going to drop. So always keep in mind to have as less amount of lights as you can. So right now we have two lights and the scene looks a little bit better than before.

Skip to 3 minutes and 45 seconds So there are many more things I can say about the lights but right now I’m going to leave it here and go to the next part.

Lighting and shading

The illusion of light and shade helps 3D objects appear more realistic. In this video, Javier explains how you can simulate light and shade in your scene.

There are three main types of light that you may use:

  • Omni-light: A light that shines in all directions from a single point (like a light-bulb)
  • Spotlight: A light that shines in a specific direction (and with a specific radius) from a point (like a spotlight)
  • Directional light: A light that illuminates all objects in the scene from the same direction (like the sun)

When would you use each type of lighting? For example, why would you use directional light as opposed to a spotlight?

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