Dynamically Lit Objects

Checked with version: 2017.3


Difficulty: Intermediate

Dealing with dynamically lit objects, especially large objects require more tricks than their static counterparts. Objects that are non statically lit in many cases are expected to change position, hence the need for dynamic lighting information. Dynamic objects have to work with these limitations in mind when predetermined lighting calculations aren’t an option. Here are some things to consider to improve the quality of dynamic object lighting:

  • Light Probe Proxy Volume (LPPV). Surfaces of dynamic objects that aren’t lit by dynamic lighting typically use Light Probe data to fill in their lighting information (In a Scene where probe is not present Environment Lighting is used). Depending on lighting strategy used in the setup of the Scene, this can range from indirect lighting information down to shadowing and baked diffused probe lighting information. This Light Probe strategy usually works fine for small dynamic objects, however larger objects require a finer granularity of Light Probe lighting. This is where Light Probe Proxy Volumes comes in. Check Unity manual for LPPV guide. Using Light Probe Proxy Volumes allow a large dynamically lit object to use more than a single Light Probe resulting in higher lighting accuracy.

The example above showcases how the capsule with LPPV demonstrate higher accuracy of Light Probe sampling despite only using 2x2x2 Volume grid.

  • Per object baked Ambient Occlusion Map (AO) Dynamic objects only receive lighting from Light probes or ambient lights. There’s a need to precalculate an occlusion for the object, especially if the object involves a concave interior such as the tram in the example.

On the example above the tram on the left without AO applied Light Probe lighting data without knowing how to differentiate the interior and the exterior surfaces. With the prebaked AO, this map serves as a guide to reduce the intensity of light and reflection from the exterior, giving a much more grounded look.

Per object Ambient Occlusion offline baking can even give further detailed occlusion by baking from higher detailed mesh to lower detailed mesh similar to how Normal map baking works.

NOTE: Per object AO doesn’t interact with other Dynamic object, for example if a dynamic object such as character entering the tram, it will be receiving Light Probe data from the scene and doesn’t necessarily match the occlusion of the tram interior.

  • Local Reflection. Most dynamic objects don’t warrant their own reflection, however for objects that involve concave interiors, attaching a reflection probe to the object and allowing it to run in realtime can help reduce false reflection hits coming from the environment reflection probe.

Exaggerated material to showcase reflection issues.

  • Fake Shadows or occlusion based on assumptions. If certain assumptions can be made for an object, there are tricks that can be used to improve visual quality. In this sample shown below, the tram is expected to be always on rail and in order to help its ground light occlusion in shaded area, a simple multiply transparent material plane is placed.

Similar tricks usually used in other games where under a character there’s a blob shadow projector instead of the character casting real shadows. In real time rendering, if you can find a tricks that works and are cheap in performance usually it can be used as a viable solution.

There are certainly more tips and tricks that can be done for improving visual rendering. The above list should give content creators confidence in thinking of solutions for different kinds of visual target requirements.


  1. Introduction to Lighting and Rendering
  2. Choosing a Lighting Technique
  3. The Precompute Process
  4. Choosing a Rendering Path
  5. Choosing a Color Space
  6. High Dynamic Range (HDR)
  7. Reflections
  8. Ambient Lighting
  9. Light Types
  10. Emissive Materials
  11. Light Probes
  1. Introduction to Precomputed Realtime GI
  2. Realtime Resolution
  3. Understanding Charts
  4. Starting the precompute process
  5. Probe lighting
  6. Unwrapping and Chart reduction
  7. Optimizing Unity's auto unwrapping
  8. Understanding Clusters
  9. Fine tuning with Lightmap Parameters
  10. Summary - Precomputed Realtime GI
  1. Lighting Overview
  2. Lights
  3. Materials
  4. The Standard Shader
  5. Textures
  6. Using Skyboxes
  7. A Gentle Introduction to Shaders
  8. Using detail textures for extra realism close-up
  9. Frame Debugger
  1. Cameras
  2. Image Effects: Overview
  1. Meshes
  2. Mesh Renderers and Mesh Filters
  1. Where to Start?
  2. Preparing Unity Render Settings
  3. Lighting Strategy
  4. Modeling
  5. Standard Shader/Material PBS and texturing
  6. Lighting and Setup
  7. Understanding Post Process Features
  8. Dynamically Lit Objects
  9. Sample Project File
  1. Using Cameras
  2. Using Lights
  3. Fun with Lasers!
  4. The Particle System
  5. Cinematic Explosions - PIT
  6. Cinematic Composition - PIT
  7. Image Effects: Overview
  8. Fun with Explosions!
  9. Exploring the Blacksmith Environment
  1. Turning it up to 11: Making Unity 5 look Awesome!
  1. Substance - Introduction
  2. Substance - Understanding PBR
  3. Substance - Working with PBR in Unity
  4. Substance - Using Substance materials in Unity
  5. Substance - Optimization for Substance materials
  6. Substance - Creating rock shapes
  7. Substance - Creating rock material, Pt 1
  8. Substance - Creating rock material, Pt 2
  9. Substance - Creating the dirt ground material
  10. Substance - Creating the rock ground material, Pt 1
  11. Substance - Creating the rock ground material, Pt 2
  12. Substance - Publishing the Substance
  13. Substance - Creating a blocking scene
  14. Substance - Creating the ground model
  15. Substance - Modelling the rock assets
  16. Substance - Texturing the upper body
  17. Substance - Exporting textures from Substance Painter
  18. Substance - Creating a scene in Unity, Pt 1
  19. Substance - Creating a scene in Unity, Pt 2
  1. Introduction and Goals
  2. Flame Particles Overview
  3. Particle Emission and Color
  4. Adding Movement To Particles With Noise
  5. Creating The Ember Particles
  6. Adding Lighting To Particles
  7. Creating Sparks With Particle Trails
  8. Particle Question and Answers
  1. Introduction and Goals
  2. Adding a Second Camera
  3. Adding Minimap Icons
  4. Render Textures and UI
  5. Adding A UI Mask and Border Image
  6. Questions and Answers
  1. Session Introduction
  2. Rendering In Unity
  3. Anatomy Of An Unlit Shader
  4. The Vertex Function
  5. The Fragment Function and Color Tint
  6. Making A Transparent Shader
  7. Displacing Vertices and Clipping Pixels
  8. Questions and Answers
  1. Introduction and Session Goals
  2. The VideoPlayer Component
  3. Texturing Objects With Video
  4. Playing and Pausing
  5. Playing A New Clip
  6. Displaying Current Time and Clip
  7. Animated Playhead
  8. Questions and Answers
  1. Overview and Goals
  2. Tonemapping and Color Grading
  3. Camera Movement & Animation
  4. Post Processing Volumes
  5. Timeline & Cinemachine
  6. Questions and Answers