Types of Lighting
Directional Light
The directional light in the unreal engine is their representation of sunlight. Set at a distance so far away it could be referred to as an infinite distance. This allows all, and any, objects in the world scene to cast shadows that run parallel with each other.
There are five subdivisions of light that make up directional light, these are:
- Light – The light emitted by the directional light, including it’s energy and colour, along with any shadows the light casts.
- Light Shafts – These effect the light bloom (glow) in the worlds atmosphere or fog.
- Lightmass – The saturation of light within a scene effecting the penumbra (the potion of a shadow that contains a small amount of light emitted from the light source).
- Light Function – Is a material applied to a light to filter it’s intensity.
- Cascaded Shadow Maps – Are the maps of the shadows created by a light source.
Sky Light
The sky light illuminates any parts of the scene that are not directly lit by the directional light. This reduces the natural look of shadowing on the unlit sides of object in a scene, giving them a brighter, and more visible, face, while still retaining some of the shadow it would normally have. This is best displayed in the two pictures below, the first has no sky light while the second does.
As you can see they both have shadows but the second picture allows the player to see more information in the shadowed area.
Spot Light
The simplest example of a spot light is a torch beam. It is projected out in a cone shape, as if there was a solid reflective material focusing the light in one direction. The spot light is broken into two emissions, an inner cone and an outer.
The inner cone casts the full brightness of the light. While the outer casts a softer light around the inner light.
Below is a picture demonstrating the spot lights effect:
Point Light
A point light is a radial light emitting source, much in the same way a light bulb radiates light. They emit light radially from a central point. A good use of a point light would be in the light projection of a fire or flame torch. This allows the light to travel out at 360 degrees.
Below is a picture of how a point light works:
See how the light shines in a circle on the floor. This represents the 360 degree emission, if there were more solid surfaces, like walls or a ceiling, the light would hit these in the same way. Also notice how the light still illuminates the edge of the curved structure to the right in the picture. This shows that the point light has a fast fall off in the the light it emits as the light is much dimmer than the light on the boxes, or floor beneath.
Static Lighting vs Dynamic Lighting
Static Lighting
Static lighting is baked into a lightmap prior to gameplay. While this is highly efficient, to the cost of processing, it means that their illumination and shadow information can never be moved.
Dynamic Lighting
Dynamic lighting, on the other hand, is a fully movable lighting system. Meaning wherever the player moves the light effect moves with them. Much like the real world where a moving object casts a moving shadow as well as how the light changes on it’s structure.
Both light sources have their uses though I fell static lighting should only be used in specific instances, lighting small areas, such as a streetlight, or an object on a pedestal, or similar things.
Dynamic lighting is a more versatile light tool. Because the light is being mapped from all directions, in every frame, this means the light cast, refraction, and the shadows will be more defined and clearer to the eye. Giving a much richer scene that is more believable to a player.
I found a person making the same comparisons on line. The first picture shows a scene with dynamic lighting. The second uses static in the same scene:
Under the bunk beds on the left it is easy to see the sharper shadow under the dynamic light. On the right of the picture it is easier to see the shadows cast by those beds. Both of these factors, along with the general definition of colour in the scene, show that dynamic lighting is superior to static.
Auto Exposure (Eye Adaptation)
This mimics the natural affect of light intensity transitions on the human eye. Much like walking from a dark cellar into a bright sunlit day.
When in the cellar the room is gloomy and as the eyes adjust some detail can be seen. This is due to the pupils dilating, allowing as much ambient light in as possible. As you move toward an opening, where the bright sunlight streams in, all you can see is the overwhelming light fill the hole while losing some, or all, of the ability to see in the dark cellar. Upon exiting the cellar the sunlight overwhelms the eye, because the pupil is fully dilated to let in as much light as possible. This sudden shock hurts, burning the retina, with the flood of light. After a few seconds the eye recovers, the pupils contract, and the eyes adjust to the new volume of light they receive.
The same happens if the light sources are reversed. Except going from a bright environment to a dark one doesn’t hurt, unless you walk into something before your eyes adjust.
This is the effect unreal have applied to their engine and the kindly posted some pictures to display this.
Static, Stationary, and Movable Light
Each of the light sources available in the unreal engine have three mobility settings
Static Light – This light cannot be changed in the game. It is the fastest rendering method for baked lighting and therefore the cheapest expenditure on the processor.
Stationary Light – This light contains the shadowing and refracted light from it’s baked lighting. Unlike static light you can change the colour and intensity in game, though the light does not move but does allow partial baked lighting.
Movable Light – Is a totally dynamic light and allows dynamic shadowing. As a result it is the slowest at rendering and the costliest in performance. Of the three it is the most flexible in gameplay.
Build Light Settings
There are four different levels of lighting quality in the unreal engine, preview, medium, high, and production, preview being the lowest and production the highest. The four light building options are:
Production – Best quality but takes the longest to render.
High – Looks good but take a long time to render.
Medium – Lower quality lighting but renders quicker.
Preview – The lowest quality lighting with the fastest render time.
When the light settings are built the engine makes a map of all of the actors (quality adds detail), lights, and the size of the level in the scene and how the the light and shadows effect them. Because of this the higher light settings will take longer to process.
A lightmass importance volume will aid in lowering the lightmap size and upgrade the efficiency. This focuses the photons used in the lightmap to a controlled area in the level. Applying that area with detailed indirect lighting. The area outside of the importance volume get a bounce of a lower quality indirect lighting.
Lighting Test in Unreal Engine 4
I decided to build a small scene to test the different lights available in the unreal engine. Starting with a dark room with no light in it. Each scene contains the same items, a chair, a table, and a rotating sword.
The second room was lit by a point light. I found it interesting to see that the light reached as far as the chair, as well as lighting the niche containing the table and sword.
The third room was lit by a spot light. As expected only the table and sword were lit by the light, it didn’t even stretch to the nearby walls.
The final room had three tables and three chairs. Each lit by a point light, a spot light, and an up lit point light. There were also some windows in the walls and one in the ceiling. These were for the light movement of the day night cycle outside, to see how the light acted within a room. It was interesting to watch the sun light travel across the floor as the sun moved overhead but no light moved through the side windows because of the sun’s rotation directly overhead.
Every world needs a day/night cycle. For added effect I imported five spheres, created a master material and coloured all of the spheres red. In order they are metallic, roughness, specular, opaque, and emissive.
I though that the swords movement was not enough so I modified it to capture the lighting more effectively.
Week 2
Engine Scalability Settings
The Engine Scalability Settings, found under Settings in the viewport, allow you to adjust the lighting effect quality in a project. A perfect use for this is if you have a sub-standard computer, that lags while building a project, these settings allow you to turn down a multitude of effects to aid in the performance of the computer while building. When done and ready to finally process the game all you need to do is turn them all back up.
I decided to run some comparisons.
Firstly I took a picture with everything on epic and the resolution at 100%.
secondly I turned everything as low as possible.
Obviously the graphics looked like some retro game from the 1980’s. Also there were no shadows at all.
To show this more clearly I turned the resolution back up to 100% and kept all the other settings on low. As you can see no shadows.
I decided next to show the same settings in one of the darkened rooms to see if there were any noticeable differences in there.
The room seemed very well lit in all places. This was to be expected with very little lighting effects manipulating the scene. In contrast I turned all of the settings back up to epic.
All back to normal. With the light behaving in an expected way in the scene.
There was one more play with, cinematic.
In the viewport I could see small changes occurring as I flicked between the two but nothing that was easily definable in pictures. Until I saw the shadows cast by some buildings.
The first is at epic setting.
The second at cinematic.
As you can see the shadow in the cinematic shot is more defined and less raggedy. This effect was noticeable in other details, especially in the detailed reflection on the specular sphere, but as I said the detail was not as apparent in it’s comparison.
An brief explanation of what each of the setting effects in the scene is below:
- Resolution Scale – Directly effects the resolution of the detail on screen.
- View Distance – At maximum setting it allows all actors to be drawn into the scene. The lower the setting the higher the cull of distant objects, starting from the furthest point out and working inwardly with each drop in setting.
- Anti-Aliasing – Effects the quality of edge definition in the scene.
- Post Processing – Effects the post processing quality in the scene.
- Shadows – Effects the shadowing in the scene.
- Textures – Effects the quality of the textures used in the scene.
- Effects – Effects the effects, such as translucency and refraction that are in the scene.
- Foliage – Effects the lighting detail on any plants or trees in the scene.
Increasing Lightmap Resolution
This is generally used for cinematics. Giving a clearer, more defined, shadow in the scene. This can be effected directly on the actor, via the details panel, lighting, override lightmap resolution to 512, 1024, 2048, 4096. This can only be used if the lightmap has been baked onto the mesh. Unreal has a tick able option when importing a mesh but i am not sure how effective this is yet.
Optimisation Tools
Lightmap Density
Located via Lit – Optimisation Viewmodes – Lightmap Density. This is where the computation of the lightmap UV coordinates can be viewed. The lightmap density is the volume of indirect lighting available in the scene. It displays something like a heat map.
As far as I can tell the brighter colours, greens, have the most light reflection/absorption, while the reds have least. This is based upon the structures that have broken geometry, doors and windows, need more light bounce detail because of there structure and how it needs to be lit equally. The red in the picture is on an opaque material, so much lower light recalculations are required on this object.
Statistics
Found under window/statistics.
This is the statistical calculated data encompassing all actors and assets within the level. Each items data is used to calculate the light movement, absorption, and reflection on each object in the level. Allowing the light to interact on a believable level as the player move across the scene.
Lightmass Importance Volume
The lightmass importance volume does what it says, it adds more light (mass) to the objects within the bounds of the volume, making them more important.
This is done by increasing the number of photons within the volume area because of this light building times will increase exponentially. This makes the saturation of indirect lighting more dense, allowing a higher volume of indirect light to add a more realistic feel to the affected area.
Everything outside of the volume will not be effected and will have a default amount of indirect lighting assigned.
When one is added or amended lighting must be rebuilt to incorporate the new change in information.
Lightmass
Swarm Agent
The lightmass is a lightmap calculating light interactions, like shadows or diffusion. To communicate this between the the lightmass and the editor a swarm agent is used. This is used to calculate expensive computations, such as high quality global illumination, as well as all of the actors within.
To effect the lightmass you must navigate to settings/world settings/ lightmass. Here there are a plethora of options that can be altered to tweak your worlds lighting.
A few will be explained here:
Indirect Lighting bounces : Is the number of times light is allowed to bounce off surfaces, starting from the light source.
Each successive bounce diminishes the light emitted. So the first will have the most light emission, the second slightly less, the third less again….and so on.
Environment Colour : Are the colour of the rays emitted from the light source.
Environment intensity : Scales the environment colour to allow a HDR (High Dynamic Range) environment colour.
Diffuse Boost : Scales the diffusion of light of all materials in a scene. Increasing this is an effective way of upping the indirect lighting in a scene. According to the unreal documentation an increase in diffuse boost must be accompanied with a raise in the light bounces.
Movable Objects in Static Lighting
Volume Lighting Samples
I could find no definitive literature on this subject. As far as I can tell a volume lighting sample is a point of reference baked onto a mesh when lighting is built. The unreal documentation speaks of them being computed within the bounds of a lightmass importance volume. Being placed upon static surfaces at a medium density and volumetric fog cannot be affected by precomputed lighting with this method.
Volumetric Lightmap Datapoints
Each of the small dark spheres in the above picture are what are used to calculate the indirect lighting of objects within the lightmass importance volumes. They are called Third Order Spherical Harmonic’s and are placed throughout the lightmass importance volume during light building. As far as I can surmise they are like light sensitive balls that calculate indirect lighting that has bounced off static meshes in the volume, they work much like microphones, picking up the increased volume of light that passes through them, giving a more realistic looking lit scene. From when the light building begins, and the protocol finds a static mesh, a smaller representation of the grid is formed around the object. This allows a much more detailed lightmap.
In this picture I placed a blue point light to help show the bounce of light within the scene. When the light is built the Third Order Spherical Harmonics are placed uniformly around each static mesh. Then the blue light’s indirect lighting is calculated as it moves away from the mesh. Diminishing as the light travels further away.
HDR Eye Adaptation
Having spoken about the light eye adaptation feature in unreal and how it mimics the eye’s altering from darkness to bright light, I now have a visual aid to help show how this is calculated. The map is very similar to the lightmap density, as it would, using the same data.
The picture shows the two hot spots of the point lights in the scene. The blue areas must be the cold spots, where little indirect lighting effects the static meshes.
I decided to place all three of the lightmap’s mentioned in this section to show, to some degree, how they come into existence to calculate the light data in the scene.
Evaluation
Unlike real life, where light just happens, artificial lighting on a computer must be created from several sources. Each working in conjunction with each other. Calculating the light from a source, how far it can travel, how much it’s light fades per meter, how the light bounces off an object, how many times, how it differs with each bounce, then all of this information transferred to the monitor for you to see in a big process. Like I said, in life light just happens. All in the blink of an eye. Seeing how the light is measured as it travels around in the engine shows how complex it is but it also gives us a great many things to consider when creating a scene. Many of the factors that make up the light can be exploited in order to make a believable scene.
Session 3
Stationary and Moveable Lights (When and Where?)
Scene Dependant
This moves back to our description of the different settings for light. Basically there are two variances. Movable and Non-Movable. Stationary and Static are non-moving lights. Whereas static lighting is lighting for an object that never changes or moves, therefore neither does the light as it has been baked into the actors texture. Stationary lighting can be moved to some degree. They can alter their brightness and colour. The basic lighting information is still baked into the static actors but the light can also be altered.
I made a video to show how the two non-movable lights react to a dynamic actor passing them. The red light is static, the blue is stationary.
This shows that the two different lights hold the same capabilities of other actor interaction. The difference being the stationary is much more flexible. Giving the low cost of a static light, merged with the more dynamic abilities of the movable light source. Though this is what makes it more expensive than static. Making stationary lights the most flexible lighting tool of the three. Because of this it is easy to see why most lights used most of the time by designers is stationary.
Evaluation
The choices between the static and stationary lights are slight. The best use would be to use both. Stationary to create more realistic shadowing on key features in the scene, and static to light the scene to a level most suitable for the atmosphere you are trying to capture.
Costs
The costs are obvious, affected by their additional lighting values.
Static lighting is the cheapest as it’s detail is baked directly onto each actor in the scene. This allows you to have as many of these in a scene as you desire. Because of this you have a much larger performance pool to play with, including the frame rate.
Stationary lighting is more expensive. Having most of it’s light baked into the scenes materials like the static it is still a cheap light. Only becoming expensive when the cast dynamic shadows from movable objects.
Another drawback is that the unreal engine only allows four separate stationary lights to be used on one object. If one more overlaps the mesh or other stationary light on the object the engine will convert this to a fully dynamic light. Adding a heavier and heavier load to the performance.
Dynamic lights are both the best lighting and most costliest. So costly that using too many will kill your performance. On the other hand you get dynamic shadows and full dynamic lighting ( you can effect the light during game play, like, move, rotate, change colour, rotation, intensity, radius, etc). A perfect example of a use of fully dynamic lighting is one used as a flashlight.
Optimisation
With all of the performance values of the different light available we can now look at further optimising the light used in game.
Create your own lightmaps on items for better shadows. Then only use up to four shadow casting lights on any object within range. This will add suitable light to your scene, using the shadow casting lights to define the shadows themselves, placing these in the scene first will give more control over this process. When done you can add as many non shadow casting lights as desired, to fully light your scene.
Evaluation
Costs always depend on how you spend them. Obviously the best light is the most expensive but don’t be fooled by it’s glitter. A careful selection of some dynamic lighting in key areas will suffice. The rest of the scene can be lit with the much cheaper static lighting to compensate. As most games are linear the lighting in most places will usually be coming from one direction only. The real problem arises when the scene is much larger and all areas are equally important, like a free roam game. The obvious solution to cost here is to make small chunks of that large area. Breaking each the map into sections where the lighting will not effect performance as much. How you separate them is entirely up to you.
Shadow Frustums
The shadow frustum is the two dimensional shape of the shadow cast by a three dimensional object.
In optimisation the best place to start is where to place the shadow creating light for the best results within it’s radius. Once this is achieved lighting of the scene can continue.
Dynamic Lighting
Movable lighting is the most superior lighting available in the unreal engine at the moment. As well as having fully dynamic lighting and shadows it can also change position, brightness, colour, rotation, position, falloff, radius, and almost every other property it has.
Full Dynamic Sun Cycle
As I mentioned earlier I created a day/night cycle. This shows dynamic lighting perfectly.
As the sun moves around the playing area, mimicking the suns rotation around a planet, it casts light from it’s position with every new frame. This adds a new light angle. Casting shadows at a new angle every time it moves position in the sky. Just as it would in real life.
Moving Lights, Optimisation
Moving lights cast, whole scene, dynamic shadows. This is very expensive for performance. With each mesh in the scene the cost grows. This can be lowered by attenuating the radius of the dynamic light, creating fewer dynamic shadows.
More factors to consider with movable lighting is it’s intensity, the brighter the further the light travels, illuminating more in a scene, costing more performance.
Also the attenuation radius and cone angles must be optimised for the sake of performance. Having a light that needlessly creates lighting information is costing you performance.
Using Light in a Large Scene
To better demonstrate the available light alteration tools I have decided to change the sky to a dusk, where the sky above has just started showing stars.
My objective is to darken the sky enough to show stars, stay blue, have a bright horizon turning red, and the clouds reflecting the red. I began with some testing of the major settings. Firstly I went to the directional light and altered the colour,
intensity (full),
intensity (none),
the source angle (0),
source angle (full).
Next I went to the sky sphere to alter the colouring of the sky itself. The first three were altered to a suitable red. The colour of each was not very dissimilar to the others. Now I needed to lower the brightness of the sky itself.
I changed the zenith colour to a dark blue and added more clouds to show off the red tinge.
I needed to lower the ambient light in the scene and found the answer in the sky sphere under intensity. This pic shows the scene with zero,
and this has the intensity on full. I settled for 0.5 finding a nice darklit night sky brightness.
Then went back to the directional light and moved the sun actor to the horizon. Remembering to click on the sky sphere when done in order for it to move in the sky.
The red of the sky was showing some nice effects on the waves.
The stars were becoming visible, I went to the sky sphere and turned up their brightness till they just became visible.
Sky light intensity at 0.2,
and at 0.5.
With a nice sky complete I noticed a penumbra casting over my character. Showing the refracted light in my characters shadow.
Evaluation
Changing the sky setting was not particularly difficult once I had an idea of which tools to use and how they effect the scene. The longest part of the process was the tweaking until I had something I wanted.
Exponential Fog
Exponential, meaning growing at a mathematical rate, is how fog scatters in the real world and in the unreal engine.
I decided to add a contrasting fog to the red sky. The green fog I saw many times on Scooby Doo as a child would be nice. I decided to take some screen shots of the different effects.
This one is no fog,
fog density low,
And high.
The fog height falloff at 0.4 (the setting I chose),
this is it at minimum,
and maximum.
The fog’s opacity at maximum,
And minimum.
Having played around with the settings a bit i finally decided upon this,
I think the green contrasts nicely with the red. I feel it looks like an eerie mist brought in by the sea.
The final setting worth reporting on was the cut off, this is where the fog ends, or begins. The first pic shows the distance at a low setting,
And this was the max setting. The move arrows at the centre of the picture is the structure in the other pics.
For the final small project of the two atmospheric adjustments is below.
Evaluation
The fog manipulation was as intuitive as changing the sky, once I knew which to effect and what they did it was just a matter of tweaking. The most interesting thing, which made sense once I had done it, was, when I put the height falloff to full. All of that lovely red in my sky vanished. Obviously it was due to the scene being full of fog, which diffused the light colour that hit it and as the light was quite a bright colour the scene changed to suit.
Overall the fog is a very useful tool. Whereas the sky reflects the day or environment, fog is a totally different beast. It adds menace to a scene, obscuring, or hiding, any potential threat beyond it.
Light and Reflection
Sphere Reflection Capture Node
Placing one of these in a scene adds extra reflective detail. This can be seen in the two pictures below. The first has no reflection capture, the second has.
It does this by saving images of it’s surroundings. To do this without one would be too expensive and slow, having to capture the scene for every reflective object for every frame.
Careful Planing is required when using reflection captures. Make sure you don’t overlap them as it will be costly.
Real Time Rendering
To show how the real time rendering works I changed the light from stationary to movable in both the directional light and sky light.
First the directional light.
Movable,
Stationary.
The most noticeable difference is in the shadows. The stationary light has much sharper definition, probably due to the baked lighting.
Now the sky light.
Stationary,
Movable.
The difference is much harder to spot in pictures but easier as you click the change.If you look closely at the two pics the stationary lit scene has a darker, fuller, colouring. When the movable light is enabled the rich colour fades slightly.
Distance Field Ambience Occlusion
This allows shadowing for movable sky lights, precomputed around each mesh.
We were tasked with using the distance field ambient occlusion to highlight all of the cracks and crevices within the ruined castle in the sea scene.
Firstly we need to activate it.
Go to project settings, rendering, lighting, and check the box labelled ‘Generate Mesh Distance Fields’. The engine will then ask if you want to restart it now or later.
Once restarted we can check the map via show, vizualise, distance field ambient occlusion. The resulting map will look something like this.
The results of this process allow the programmer to add colour to all of the cracks and crevices in game. Effective for a mossy backdrop, or something suitable for the style of game, like red for a horror game (giving the illusion the scene is bleeding, or flourescent green for a radioactive level. All in all a nice touch to add depth to a scene.
To add colour to all of the cracks go to sky light/ occlusion tint. The colour still wont be added until you open the colour selector and move the arrow on the second bar.
With the arrow moved halfway you can see the effect it has on the scene. Adding a lushness.
On full the colour screams. this could be useful for the radioactive scene I mentioned before.
Evaluation
My understanding of correct use of lighting is growing. When messing about with the scooby doo scene I saw the effect the light had on the scene. Not only the colours around the scene but how they can be set to quite a low illumination, in reality, and via the sky light/ intensity. Cranking this up can illuminate the scene around your player without changing the overall look of the scene, the secret is to have it set at just enough. Just enough to see where you are going without compromising the atmosphere.
Session 4
Distance Field Shadows
Ray Traced Distance Field Shadows (RTDF) is the shadowing for movable light sources. It uses the distance field of the rigid mesh to compute the shadow. A ray is traced from the point that is being shaded, through he scene’s distance fields, towards each light. A cone trace is then projected from the closest distance from the occluding object.
As a result the shadows are softer than baked ones.
The size of the projected shadow is governed by the source radius of the light, the larger the radius the the more shadow.
I decided to test the shadows effect by changing the settings from minimum, to normal, to maximum.
Minimum:
Normal:
Maximum:
As far as I can see there is no difference between normal and maximum but on minimum there is some loss of detail from the detail of the fence shadow.
Creating a Night Scene
To aid with this I found a nice video that shows how to create a night scene, along with a moon with aura.
I created a new version of the Infinity Blade Grasslands map, for contrast with the day scene.
For a start I added a moon, placing it at the edge of the sky sphere.
To this I added an emission, for it’s glow.
The parameter would allow me to directly alter the emissiveness of the glow.
After that was the process of eliminating the sun and it’s light value. Beginning with the sky sphere. Removing all of the sun’s brightness and altering the colour of the light at it’s different altitudes (zenith, horizon, and overall).
In the light source I altered the intensity to a lower setting and changed the light colour to a darker blue, this is a natural occurance when light volume lessens.
Finally, the sky light. Where I altered the light colour.
For more of a colour blend in the scene I altered some of the world settings ( I followed the video tutorial for these settings and have not fully tested the settings myself).
Firstly the environment colour was darkened to give the scene a darker feel. Lowering the environment intensity so the colour did not overpower the scene. Finally I checked the use ambient occlusion box, to utilise that.
To add some more atmosphere to the scene I altered the post process volume settings, firstly I unbound it, to effect the entire scene outside of the volume.
Then I altered the tint shadow, to blend it’s colour into the scene 
Finally I altered the scene colour tint.
With all of these actions done I built the light to see the effects in place.
The change was so noticeable between pre-built and built lighting. So much so I am placing both videos to show how deceiving the pre-built lighting is.
Here is the pre-built lighting.
And the built lighting with the same light information.
Emissive Light as a Light Source
A piece of handy information is the fact that an emissive material can be used as a light source. Previously I had been using emissive materials for their glow and assumed that this would carry into the world in a natural manner, I was wrong. For this to work, in a conventional way, I need to tell the mesh to transmit it emissive light as a static one. As shown in the picture below.
For the effect to occur the light must be built. Here are two shots showcasing this, the first is normal emission, the second the emission has been enabled and the light built:
Building a Lit scene
The final part of this unit was to apply the information learned to a scene. The scene must have an animation to show the movement of cast shadows. This was achieved by making a day night cycle.
For the scene itself I created a mountain range around the scene I had so far constructed in this unit, I think the moving sun would create some nice light/shadowing as the sun passes overhead.
Along side the test pieces I constructed a single room and filled it with some furniture I created.
To showcase some of the lighting, and how it effects the scene, I made a table lamp and room lights that could both be toggled on and off. These were accompanied by two, permanently, lit lights (one a lamp on a desk the other lights in a cabinet).
This exercise is to show the way the engine, not only lights a scene but how the light effects the scene and the construction of shadows.
I have posted a video of the final results.
Evaluation
Lighting is important, otherwise we would continually bump into things. Having the best light sets off a scene.
There is a lot of details to learn in lighting and using them all correctly will take time. I liked this unit for I am an appreciator of lighting in real life. From fiery sunsets to fireworks. The right light can make a scene.
There was so much covered in this unit, like emissive textures used as lights. The variances between unbuilt and built light. Night time, fog, shadows, sphere reflection capture node, real time rendering… and so on.
I understood most of it, gaining insight into the engines abilities, but I cannot remember as much. The sheer volume of varied topics covering light and all of it’s uses in the engine make this impossible.
To further my understanding I need to take a better look at the day and night scenes again. Seeing how the opposite effects are generated by the same controls, inverted, and how new controls play a big part in one or the other.
I think it is understandable that such a broad topic cannot be mastered with one unit so I will take it a step at a time.
My Blueprint Factory 