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Questions pertaining to point light & directional light

So I am new to UE4 and thought to first start with building a simple scene to learn the controls. Following this tutorial. Level Designer Quick Start | Unreal Engine Documentation

My first question is about the directional light. In the tutorial on the fifth page is tells me to enable ‘Atmosphere Sun Light’ . However I am unable to find this option in the details of my directional light so I am assuming the tutorial is slight outdated? In which case is this still an option? Or has it been removed?

My second and third question pertain to the point light. As you can see in this screenshot the shadow of the left point light is more blocky than the shadow on the right. I have determined it is caused because the left point light is static and the right is set to station. However I have five point lights near each other and I can not have more than two set to station without a red cross popping up. Should I instead set all the lights to movable which also has smooth shadows but a worse effect?

I am not sure how this would affect the memory in larger scenes. Would it cost more than another option?

The third question is how to remove that lens flare which is really annoying. ^^’

Thanks in advance for any help given.

Hi. I took a picture showing where the Atmosphere Sun Light option is located

As far as the point lights, I’m no expert and someone may be able to correct everything I’m saying, but from my knowing: Movable and Stationary Lights are dynamic lighting, with Movable being completely dynamic while Stationary is part baked and part dynamic.

Stationary) A Stationary Light will bake its shadows and bounced light when you build the lighting. This means that while in-game, you can change the color of the light, change its brightness, or even completely turn it off and on and the shadows will react as if a light was really being turned on and off. However, the catch to this is that you can’t move the light. If you bake the light, and then move it to another location, you’ll notice that the shadows will still move according to the light, but the shadows will display “Preview” on them, basically indicating that the baked light has been moved and now the viewport is just showing you what it will be like the next time you build the lighting.

Movable lighting) is completely dynamic. If you build the lighting and then decide you want to move the light somewhere else, the light will still be fully functional and built. Examples of this would be…I don’t know, a flashlight (more notably achieved with a Spotlight, though). That flashlight would have to be completely dynamic, otherwise it wouldn’t cast shadows. If the flashlight was Stationary, you’d be able to turn it on and off, but you wouldn’t be able to move it, so what’s the point.

Static lighting) is completely devoid of dynamics. You place it, build it, and then that’s it. As an example, if you place a SM_Rock (because it shows light bounces well) from the Starter Content, and then place a red static point light near it and then bake the lighting, it will have shadows and the rock will glow red as if there’s a light right next to it (because it is). However, if you reduce that light’s intensity to 0 - in other words, turn it off - the rock will still be glowing red and it will still have a shadow, because the static light illuminated the area permanently (by permanently, I mean until the light is re-built).

Something also to note, is that a Static light doesn’t affect the character at all. If you place a static light in the scene and build lighting, then run your character under it, the character won’t have any light shining on it and also won’t cast a shadow. However if you change the light to Stationary or Movable, the character will cast a shadow and it will also move in real-time. (Stationary character shadows seem glitchy, but I’m not sure if that’s fixable – Movable character shadows are fully and properly cast).

As you guessed it, Movable lighting is on the high end in terms of performance usage. I don’t know the exact numbers but I’ve played enough games to see that I’ve lagged extremely bad in very simple scenes, and I would always attribute that to bad lighting optimization. I say use it where it’s needed. Also to note, I made these tests in a starter level using third person blueprint. I disabled the “Cast shadows” on the Directional light so the shadows will come off specifically from the Point Light that was set up. (This was just done for the test purposes). If you want some scenes to be lit in certain colors in certain spots, or want to just light up dark areas, then go with Static. I was using Stationary lights until recently when I realized that the lights were affecting my character and he was glowing uncontrollably when I ran in front of the light.

I personally can’t say when you should or shouldn’t use what type of light, but I do know that in most cases, there’s no need to have 20 movable lights all in one room. I would just use Movable lights when, like said, it was something on the course of a flashlight or maybe a creepy ceiling lamp that is randomly swinging around showing no signs of stopping, and you want that eerie shadow swinging around the room as you walk in.

For the lens flare effect, are you talking about when you’re in a dark room and then run to an opening looking outside and it brightens your screen, and when you turn around to the room everything is dark? Or maybe not, Any way to get rid of a lot of effects, you can click [Show]](http://i.imgur.com/aOAlnYG.png) under the toolbar and then click Post-processing and uncheck Eye-adaptation or Lens Flare or whatever else. I think that might only work while in editor-view and not while in-game but I forgot how to disable it while in-game. Hope this helped.

Feeling a bit silly now, apparently I had the wrong light source selected while I was looking for the atmosphere sun light option. But thanks for making me realize that with the screenshot.

As for the lens flare, after pointing me in the right direction with how to disable it in editing mode I figured out you can disable it ingame by going into Edit->Project settings->rendering and from there looking under the ‘default postprocessing settings’ tab. The ingame lens flare is the second last in the list. :slight_smile:

The only problem I have left is that the shadows only render nice when the point light is stationary. I guess the thing left to do is experimenting with more spot lights. :slight_smile:

Thanks for your help and explaining stuff about the lights.

I know for sure that the shadow quality of objects depends on the lightmap of the object that’s having its shadows rendered. I believe it can be increased by changing the Lightmap Resolution of the object (I think that’s the way). If you open the object in the static mesh editor and in its details, scroll down to look for Lightmap Resolution (it’s usually set to 64), if you try increasing it in increments of 2 (8/16/32/64/128/256~) and see if the shadows sharpen up a bit. Is your light-build quality set to Production or Preview? You can choose how well the lighting is built by clicking on the arrow next to “Build” on the toolbar, then under Lighting Quality, change to Production. It takes longer to build the scene, but the lighting will be much better than Preview quality.

Also an added something is that if you have a large map, or even a normal size map, but want the light build to render a specific section of the map, you can use a Lightmass Importance Volume, which will build lighting only for the zone contained within it. It’s under “Volumes” in the “Modes” menu on the left side above content browser. I believe there are a lot of settings to getting shadows to look right that go beyond just static vs stationary though. But you’re welcome!