CAS Lighting Mod | A Visual Guide

ℹ️ Overview

• Created & edited with Sims 4 Studio

• No ReShade/GShade used in previews. Everything you see is how it looks in the game.

• Throughout the guide, lighting types will be indicated with a bold (KeyLight, RimLight), while parameters will be indicated with an italic (Height, Angle).

• Additional info: CAS lighting mods don’t just change the lighting setup in CAS but also for any generated sim thumbnails. They don't have any effect on the in-game lighting on sims which are edited separately.

This was meant to be shared for getting a 1k followers milestone on tumblr before I ever got here and here we are, 110k+ (!) patreon members later 😆

You can find all of my released CAS lighting mods from the link below

📥 Download

Due to the amount of screenshots I took to cover what I wanted, only a portion of them will be shown in this guide while the rest will be uploaded in the attachment.

What’s included (116mb):

1. Folders sorted by Height [ 9 folders in total ]

   • In each folder you get: screenshots from different Angles of that specific Height. Covers 360° lighting, mostly in 30° increments. The first 2 folders (Height = 0 & 1) will have 15° increments.

   • A subfolder filled with full body shots.

2. A folder for RimLight shots.

3. Extra folders with screenshots I used for this guide.

4. A text document that lists all the values used on most screenshots.

5. vyxated-CAS_Lighting_Sample.package → the mod with settings I used in the Parameters section.

📜 Tools & Resources

• 🔧 Convert RGB Hex to Decimals ; (alt)

• RGB Tutorial by SimplyAnjuta

• Studio Lighting Examples

• RGB Lighting Chart

🖼️ Descriptions & Examples

// Light types (bolded)

KeyLight0 & KeyLight1 = main light

• Change direction of light with Height and Angle.

• Works like an additive layer and is best tweaked along with AmbientLight.

• Unlike RimLight, they are not locked to a certain area of the sim and can be adjusted with different parameters.

RimLight0 = (our) right side | RimLight1 = (our) left side

• Adds a RimLight to either side of the sim. They appear mostly on the sim’s body right until the neck area.

  • Top pic: RimLight0 & RimLight1 ; bottom pic: RimLight1 only.

AmbientLight = determines how light/dark the shadow is.

• Lower value = darker shadows and vice versa.

• The lower the AmbientLight value is = the more vibrant/apparent the KeyLight gets (especially if it’s colored lights).

• Above is what AmbientLight looks like when both KeyLight and RimLight are disabled.

// Parameters (italicized)

In order to keep the majority of screenshots consistent, I used a constant value so that you can see the effect of these parameters on their own. Anything not included below is not activated unless it’s stated otherwise.

• LightBaseHeight: 0.75

• Keylight0

  • Color: 1, 1, 0 

  • Intensity: 0.9

  • SpecularIntensity: 0.8

• AmbientLight

  • IntensityMin: 0.4

  • IntensityMax: 0.4

Enable [ 1 or 0 ]

• 1 to enable, 0 to disable lighting

Height [ -x to x ]

• Above [ x ] | Below [ -x ]

• Anything more than 5 doesn’t seem to make any big changes visually.

  • Values used in pic → Height [ 3 , -3 ] Angle [ 0 ]

Angle [ 0 to 360 ] or [ 0 to +/- 180 ]

• Rotates anti-clockwise.

• Use a negative value to flip its direction.

• Values used in pic:

  • Top row → Height [ 1 ] Angle [ 0 , 90 ]

  • Bottom row → Height [ 1 ] Angle [ 180 , 270 or -90 ]

Color [ R, G, B ]

• See SimplyAnjuta's tutorial on how to change the RGB value to a specific color.

• You can also use this converter or this to skip using the calculator. You’ll use the value listed on the normalized decimal.

• Alternatively, you can combine 2 colors into 1 by assigning each KeyLight with its own color.

  • Value used above → RG (Yellow) + GB (Cyan) = The Matrix tint?? // Intensity used → [ 0.5 ]

• You can also go beyond the value of 1 to increase the intensity of said color. Color [ 2, 1, 1 ] will make the light look redder, etc.

Intensity [ x ]

• Value determines how intense KeyLight & RimLight lights up the sim.

  • Left → single KeyLight at 0.5 intensity. Angle at 0.

  • Right → 2 KeyLights, both at 0.5 intensity. Angle at 0.

• You can change the angle and intensity to get different results.

  • Left → 2 KeyLights, both at 0.5 intensity. Angle at 45 and -45 each.

  • Right → blue light at 0.5 intensity ; yellow light at 0.9 intensity.

KeyLight → Specular Intensity [ x ]

• Value determines how intense the specular light is. Only visible on items that have proper specular maps.

• The example above has 2 KeyLights activated, both at a 90° angle. One has Specular Intensity enabled (the right pictures), and one does not.

  • Value used in pic → Specular Intensity [ 20 ]

• Intensity must have value to see the Specular Intensity effect.

RimLight → Falloff [ x ]

• Value determines how far into the sim the RimLight goes.

• 0 value = extends the RimLight the furthest. The bigger the value is, the tighter the falloff gets. Compensate the small exposure on higher falloff value by increasing the RimLight’s Intensity.

• Values used in pic:

  • 1st pic: RimLight0 [ 6 ] ; RimLight1 [ 0 ]

  • 2nd pic: RimLight0 [ 0 ] ; RimLight1 [ 0 ]

  • 3rd pic: RimLight0 [ 0 ] ; RimLight1 [ 6 ]

  • 4th pic: RimLight0 [ 6 ] ; RimLight1 [ 6 ]

AmbientLight → IntensityMin [ x ]

• Affects the lower part of the body and right side of the eyeball.

  • Value used in pic → IntensityMin [ 1 ] IntensityMax [ 0 ]

AmbientLight → IntensityMax [ x ]

• Affects the upper part of the body and left side of the eyeball.

  • Value used in pic → IntensityMin [ 0 ] IntensityMax [ 1 ]