The following screenshot shows when the Point Light has its default Attenuation Radius of 1000. The radius of the three blue circles is based on the attenuation radius of the Point Light and is used to show its area of effect on the environment.

The following screenshot shows when the attenuation radius is reduced to 500. In this situation, you probably cannot see any difference in the lighting since the radius is still larger than the room itself:

Now, let us take a look at what happens when we adjust the radius much smaller. The following screenshot shows the difference in light brightness when the radius changes. The image on the left is when the attenuation radius is set as 500 and the right when attenuation radius is set as 10.

Another setting for Point Light is Intensity. Intensity affects the brightness of the light. You can play around the Intensity value to adjust the brightness of the light. Before we determine what value to use for this field and how bright we want our light to be, you should be aware of another setting, Use Inverse Squared Falloff.

Use Inverse Squared Falloff

Point Lights and Spot Lights have physically based inverse squared falloff set on, as default. This setting is configurable as a checkbox found in the Light details under Advanced. The following screenshot shows where this property is found in the Details panel:

Inverse squared falloff is a physics law that describes how light intensity naturally fades over distance. When we have this setting, the units for intensity use the same units as the lights we have in the real world, in lumens. When inverse squared distance falloff is not used, intensity becomes just a value.

In the previous chapter where we have added our first Point Light, we have set intensity as 1700. This is equivalent to the brightness of a light bulb that has 1700 lumens because inverse squared distance falloff is used.

To adjust the color of Point Light, go to Light | Color. The following screenshot shows how the color of the light can be adjusted by specifying the RGB values or using the color picker to select the desired color:

The unit for the outer cone angle and inner cone angle is in degrees. The following screenshot shows the light radius that the spotlight has when the outer cone angle = 20 (on the left) and outer cone angle = 15 (on the right). The inner cone angle value did not produce much visible results in the screenshot, so very often the value is 0. However, the inner cone angle can be used to provide light in the center of the cone. This would be more visible for lights with a wider spread and certain IES Profiles.

IES Light Profiles can be downloaded from light manufacturers' websites. Here's a few that you can use:

From Content Browser, click on Import, as shown in the following screenshot:

I prefer to have my files in a certain order, hence I have created a new folder called IESProfile and created subfolders with the names of the manufacturers to better categorize all the light profiles that were imported.

Continuing from the previous example, select the right Spot Light which we have in the scene and make sure it is selected. Go to the Details panel and scroll down to show the Light Profile of the light.

Then go to Content Browser and go to the IESProfile folder where we have imported the light profiles into. Click on one of the profiles that you want, drag and drop it on the IES Texture of the Spot Light. Alternatively, you can select the profile and go back to the Details panel of the Light and click on the arrow next to IES Texture to apply the profile on the Spot Light. In the following screenshot, I applied one of the profiles downloaded from the Panasonic website labeled 144907.

I reconfigured the Spot Light with Intensity = 1000, Attenuation Radius = 1000, Outer Cone Angle = 40, and Inner Cone Angle = 0.

Next, I deleted the other Spot Light and replaced it with a Point Light where I set Intensity = 1000 and Attenuation Radius = 1000. I also set the Rotation-Y = -90 and then applied the same IES Profile to it. The following screenshot shows the difference when the same light profile is applied to a Spot Light and a Point Light. Note that the spread of the light in the Spot Light is reduced. This reinforces the concept that a Spot Light provides a conical shaped light with a direction spreading from the point source outwards. The outer cone angle determines this spread. The point light emits light in all directions and equally out, so it did not attenuate the light profile settings allowing the full design of this light profile to be displayed on the screen. This is one thing to keep in mind while using the IES Light Profile and which types of light to use them on.

Open Chapter4Level_DirectionalLight.umap and rename it Chapter4Level_Skylight.umap.

In the previous example, we have added sunlight control in the Directional Light. Build and compile to see how the level now looks.

Now, let us add a Sky Light into the level by going to Modes | Lights and then clicking and dragging Sky Light into the level. When adding a Sky Light to the level, always remember to build and compile first in order to see the effect of the Sky Light.

What does a Sky Light do? Sky Light models the color/light from the sky and is used to light up the external areas of the level. So the external areas of the level look more realistic as the color/light is reflecting off the surfaces (instead of using simple white/colored light).

The following screenshot shows the effect of a Sky Light. The left image shows the Sky Light not in the level. The right one shows the Sky Light. Note that the walls now have a tinge of the color of the sky.

The common light/shadow definitions are as follows:

In a game, we always want to have the best performance, and Static Light will be an excellent option because a Static Light needs only to be precomputed once into a Light Map. So for a Static Light, we have the lowest performance cost but in exchange, we are unable to change how the light looks, move the light, and integrate the effect of this light with moving objects (which means it is unable to create a shadow for the moving object as it moves within the influence of the light) into the environment during gameplay. However, a Static Light can cast shadow on the existing stationary objects that are in the level within its influence of radius. The radius of influence is based on the source radius of the light. In return for low performance cost, a Static Light has quite a bit of limitation. Hence, Static Lights are commonly used in the creation of scenes targeted for devices with low computational power.

Stationary Light can be used in situations when we do not need to move, rotate, or change the influence radius of the light during gameplay, but allow the light the capacity to change color and brightness. Indirect Light and shadows are prebaked in Light Map in the same way as Static Light. Direct Light shadows are stored within Shadow Maps.

Stationary Light is medium in performance cost as it is able to create static shadow on static objects through the use of distance field shadow maps. Completely dynamic light and shadows is often more than 20 times more intensive.

Movable Light is used to cast dynamic light and shadows for the scene. This should be used sparingly in the level, unless absolutely necessary.

Group items in the same area together when possible and rename the entity to help you identify parts of the level more quickly. These simple extra steps can save time when using the editor to create a mock-up of a game level.

If you plan to extend the game level on your own, open and load Level4.umap. Then save map as Level4_MyPreBuilt.umap. You can also open a copy of the extended level to copy assets or use it as a quick reference.

Creating windows and doors

Now that we are done with rooms, we can work on the doors and windows.

Part 1 – creating large glass windows for the dining area

To create the windows, we use a subtractive Geometry Brush to create holes in the wall. First, create one of size X144 x Y30 x Z300 and place it right in the middle between the ceiling and ground. Duplicate this and convert it to an additive brush; adjust the size to X142 x Y4 x Z298.

Apply M_Metal_Copper for the frame and M_Glass to the addition brush, which was just created. Now, group them and duplicate both the brushes four times to create five windows. The screenshot of the dining area windows is shown as follows:

Part 2 – creating an open window for the window seat

To create the window for the window seat area, create a subtractive geometry brush of size X50 x Y280 x Z220. For this window, we have a protruding ledge of X50 x Y280 x Z5 at the bottom of the window. Then for the glass, we duplicate the subtractive brush of size X4 x Y278 x Z216, convert it to additive brush and adjust it to fit.

Apply M_Metal_Brushed for the frame and M_Glass to the addition brush that was just created.

Part 3 – creating windows for the room

For the room windows, create a subtractive brush of size X144 x Y40 x Z94. This is to create a hollow in the wall for the prop frame: SM_WindowFrame. Duplicate the subtractive brush and prop to create two windows for the room.

Part 4 – creating the main door area

For the main door area, we start by creating the doors and its frame, then the brick walls around the door and lastly, the remaining concrete plain wall.

We have two doors with frames then some brick wall to augment before going back to the usual smooth walls. Here are the dimensions for creating this door area:

BSPs needed	X	Y	Z
Actual door x 2	20	116	250
Side frame x 2	25	4	250
Top frame	25	242	5

Here are the dimensions for creating the area around the door:

BSPs needed	X	Y	Z
Brick wall side x 2	30	52	340
Brick wall top	30	242	74
Smooth wall left	30	126	340
Smooth wall right	30	130	360