Welcome back one more week, dear readers!
Today, and as a previous step before building the lighting of our scene, we are going to prepare a level for such task. To do so, we could rely on any of the default maps created with the editor’s different blueprints. Instead of that, we’ll create one from scratch so we can understand how Unreal Engine really works behind the scenes. Let’s get to it!
As a start, let’s create a new level. Doing so it’s easy, as seen on the next image, but it will be an empty and desolated place. All black. And that’s what we are going to talk about, how to take that dark space and turn it into a brighter realm. To do so, we’ll need some basic building blocks today – a sky light, a directional light, a sphere reflection capture actor, a post process volume, a lightmass importance volume and a sky sphere, plus the lightmass properties we’ll talk about at the end of the post.
Sky light
One of the first steps we need to do is to create a sky light. This type of light, which can be found on the lights creation panel, is responsible for the correct physical behaviour of the light in our scene. We’ll use it to realistically light the scene, in combination with some post processing for exposure reasons.
At this stage, let’s just drag that light and drop it into the scene.
Directional light –
The main light that lits the scene, and the one responsible for rendering the shadows in a particular direction. Like we did before, just drag and drop it into the main viewport and tweak some of its values if you want – even though at this stage its better to leave it as it is.
Sphere reflection capture –
This sphere reflection capture is an important asset in order to tell the engine where it has to calculate reflections for those surfaces that have that property.
This asset can be found under the visual effects tab, and once we put it into our map it’s pretty easy to set up. Just adjust the influence radius to a value that covers all of the objects in your scene, and you’ll be ready to go.
Post process volume –
The post process volume is an asset that you can find under the visual effects tab, and it tells the render engine which area it should affect with various post processing effects. Tweaking its settings produces some of the most interesting results.
As you can see, there are many interesting values that can be configured. For example, the white balance will let you modify the warmth of the scene, and the color grading node allows to tweak and change the look of the project. There are many others, like bloom, lens flares, depth of field… they all allow for experimentation and will set you free as to where you want to go with your design. It is a really cool tool!
Lightmass importance volume –
This volume controls where the lightmass will emit photons in, so it defines which areas will be calculated according to the parameters you will specify in the lighmass options panel. In most cases you will want it to cover your entire scene, but only if you want to compute it all. It is up to you to decide, since there might be times when you don’t really need certain areas to be calculated, saving you some precious time.
It can be found under the Volumes tab.
Sky sphere –
The Sky Sphere is a blueprint already created that we are going to work with. It is a very handy asset, as it already contains a sky that can be adjusted to look like any time of the day – or night.
It can be found typing BP_Sky_Sphere on the creation search box,and you can adjust its values on the properties panel. Make sure to check out the override settings, as it will allow you to easily create a night or sunset scene.
Lightmass properties
The last setting we’ll cover today is the lightmass. The values that we tweak in here will affect the overall quality of the project, therefore its importance. Let’s see where we can find them.
Even though we’ll cover most of these settings once we deal with the final light calculations for our project, let’s see some of them. For example, some values we’ll tweak are the indirect lighting bounces, which is by default set to a number between 1 and 3. We can go higher in here – always considering that the render times will suffer a bit as well – since this will affect the quality of the scene. The quality of the illumination will be important as well, and the softness of it.
There are many more settings that can be modified, but we’ll change them before building the lighting. For now, it’s just good to get familiar with them and see what we need to change in order to improve the quality of the final build.
With all of that in mind, we are ready to build lighting, which is something we’ll do on the next blog post. This is something that might take quite a while to process, so it’s good that we are aware of all the values that can be changed to speed up the computing part. But that will be all for today, see you next week!
Cheers!
Brais Brenlla 