Titus | Lighting and Rendering Evaluation

What?

  • Give Titus high quality AAA lighting

  • Focus on:

    • Materials

    • Lighting

  • Special considerations:

    • Do this in Unreal Engine version 4.22.3; custom UE4 build

    • Beauty corner | vertical slice

    • Schedule:

      • TBD

      • Estimated development time 4 weeks

      • x1 AAA Senior/Lead Lighting Artist

      • X1 Technical Artist

Why?

  • Upgrade Titus’ visuals to highest standards of “AAA” competitors (i.e. Uncharted 4, Last of Us II, etc.)

  • Improve visual experience for vertical slice

  • Establish new (higher) visual bar for Titus

How?

  • Team: (GoDemics)Independent development team comprised of industry veterans from AAA games; mostly lead and senior artists with games and film experience (specialize in Unreal Engine lighting)

    • Roster (for Titus):

      • Senior/ Lead Lighting Artists x 1

      • Tech Artist x 1

    • Experience:

      • Battlefield

      • Uncharted 2

      • Last of Us

      • Doom (2016)

      • Many AAA franchises...

AAA Lighting Standard Examples

 
 
 
 
 
 
 
 
 
 

Ingredients for Lighting (Technical)

  • Material pipeline:

    • Calibrated textures

    • “Vetted” materials

    • Realistic BRDF surfacing

  • Lighting pipeline:

    • Calibrated lighting

    • Tone mapping

    • Realistic light functions (tuned for accuracy)

Art Ingredients for Lighting (Non Technical)

  • Contrast (value)

    • Draw player’s eye; provide scene with interest

  • Depth

    • Prevent scene from going “flat” (what most poorly lit games suffer from); support dimensionality of the game’s world

  • Surface (definition)

    • Does the lighting make each surface distinguishable; that is, can viewer tell difference immediately between something that is dry vs. wet; stone vs. wood; soft vs. hard, smooth vs. rough; etc.

Wait… But How?

  • Good news!

    • Unreal Engine 4 supports all the aforementioned features

  • Bad news!

    • The features are like “ingredients” to a recipe; and UE4 is like a bag of groceries- you can’t just empty the bag and have a five course meal, we need to put it altogether and be great chefs for this to work!

Calibrate, Calibrate, and Then Calibrate More!

 

  • We need to do the following:

    • Calibrate your scene’s lighting...

    • Don’t stop there; you have to calibrate your entire project’s lighting- across the board! This will help the entire team be on the same page

Example of properly calibrated project lighting; note the visual fidelity of the plant and its surfacing

Example of properly calibrated project lighting; note the visual fidelity of the plant and its surfacing

 
 

On the right: current uncalibrated lighting in Titus results in poor visual feedback in UE4 editors (in this example, the static mesh editor). Artists and devs will be unable to properly view and evaluate materials and textures!


Example of improperly calibrated project lighting (default UE4); note lack of surface definition and lack of details, unrealistic, among other issues

Example of improperly calibrated project lighting (default UE4); note lack of surface definition and lack of details, unrealistic, among other issues

 
 

Texturing

  • PBR calibrated textures

  • Validated textures

  • Correct compression

  • Use of (wide range) shading surface data

  • Layer masks (used with high fidelity tiling textures)

Shading

 

Implementing concept of:

  • Dielectric surfaces

  • Metallic surfaces



13.JPG
 
 
Example of dielectric material with corresponding data maps

Example of dielectric material with corresponding data maps

 

Lighting

Lighting needs to be completely redone in Titus:

  • Lighting needs to be calibrated

  • Previewer lighting (UE4) needs to be calibrated

  • Material ranges need to be validated (out of range textures break lighting)

  • Use of true 32bit HDRI skies for ambient lighting

  • Use volumetric lightmap system

  • Fix tonemapping (don’t use default tonemapping curve!)

  • Many more items...

Indirect Lighting

Flat ambient lighting:

Note the equal value and hue of lighting in the highlighted areas. In real life, light doesn’t behave this way- this is a very “video game” way of lighting, and isn’t authentic. Real ambient lighting comes from millions of directions and has subtle changes in hue and value.

 
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Lack of (accurate) GI:

This is an example of an impossibility in nature; this would never happen. On a typical clear early afternoon day, you’ll have an EV of about 15- which would produce very distinct bounce lighting and indirect shadows.

 

Example of how exterior lighting works in real life, on a typical early afternoon, with clear skies. Also note the gradient of the sky.

Also note that the indirectly lit areas, are not the same value. Because light comes from so many directions, and bounces off so many surfaces, ambient light is complex and not the same value everywhere.

 
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Skybox

To the right is the skybox texture being used in CQ_Ludus.

It’s best to have a custom 32bit HDRI skybox; custom painted/comped, removal of lens artifacts (sun flare in this case), replacement of sun in HDRI, replacement of “ground plane”, flow map support for realistic cloud movement, etc.

The current sky box material needs more features; it’s too simple/placeholder at the moment. Should include features for control of contrast, brightness, cloud movement, etc.

Many production features missing!

 

Post Processing

 
LUTs are NOT supported in the HDR rendering pipeline and should not be used, aside from lookdev.

LUTs are NOT supported in the HDR rendering pipeline and should not be used, aside from lookdev.

  • Tonemapping (currently Titus is not properly tonemapped)

  • Color grading (HDR- no LUTs)Titus is using LUTs; these are great for lookdev, bad for final production!

  • Lens exposure (currently this isn’t setup; but it needs to be!)

  • Depth of Field

 

Atmosphere

To achieve the atmosphere in the current art direction:

  • Breakup lighting (opposite of the current lighting pass; lighting is currently too uniform, which looks unnatural)

  • Volumetric lighting needed, to be married with VFX pass

  • Global material pass to add more sand, grit, etc.

  • Color grading pass

Titus_Trainingyard_01.jpg

Missing atmosphere and execution of art direction/concepts:

  • Lighting is uniform, uninteresting, no mood or “personality”

  • Lack of volumetric lighting and env fog

  • Surfaces are not “unified”; env fails to connect them

No color grading (this is fine since it should be avoided until final stages of lighting)

Future Tech: Raytracing

Titus RTX

Why Raytracing?

  • It’s the future of realtime rendering

  • Position Titus at the bleeding edge of innovation

  • Add Titus to the small list of next gen games supporting RTX (i.e. Battlefield V, Metro Exodus, etc.)

Titus can become known as a title that pushes rendering innovation forward

 

Final Thoughts…

Primary Goals:

  • For Titus to have AAA lighting on par with the top competing products in the industry

  • Improve lighting in vertical slice level (CQ_Ludus)

Stretch Goals:

  • Fix rendering pipeline

  • Improve material pipeline

  • Calibrate project lighting (global)

RTX lighting support (if interested, ask us for an example for illustrative purposes)

LightingBrandon PhamTitus