Eevee contact shadows cause light bleeding around occluded objects #66139

Closed
opened 2019-06-26 08:19:27 +02:00 by Andrew Price · 11 comments

System Information
Operating system: Win 10 64 bit
Graphics card: GTX 1080 ti

Blender Version
Broken: 2.80, 12da679fa0, 2018-06-16

Short description of error
Contact shadows cause weird light shafts to appear around occluded objects.
blender_2019-06-26_14-37-30.jpg

Exact steps for others to reproduce the error
.blend showing problem: test.blend
Watch video explaining the problem

  • Create a cube with a hole as the window
  • Create an area lamp outside the cube shining light in
  • Add an object on the floor of cube near the window.
  • Turn on contact shadows

Weird light shafts should appear around object on floor.

blender_2019-06-26_16-13-22.png

I've tried making the cube walls thick, or adding large objects on other side of the wall. But the problem persists.

I know there are many limitations of eevee that can cause light bleeding. But this is persistent, leading me to think it's a bug.

**System Information** Operating system: Win 10 64 bit Graphics card: GTX 1080 ti **Blender Version** Broken: 2.80, 12da679fa094, 2018-06-16 **Short description of error** Contact shadows cause weird light shafts to appear around occluded objects. ![blender_2019-06-26_14-37-30.jpg](https://archive.blender.org/developer/F7549335/blender_2019-06-26_14-37-30.jpg) **Exact steps for others to reproduce the error** .blend showing problem: [test.blend](https://archive.blender.org/developer/F7549337/test.blend) [Watch video explaining the problem ](https://drive.google.com/file/d/1izh0qMw7XXv929jbK0Jpzvsf10urrLCX/view) - Create a cube with a hole as the window - Create an area lamp outside the cube shining light in - Add an object on the floor of cube near the window. - Turn on contact shadows # Weird light shafts should appear around object on floor. ![blender_2019-06-26_16-13-22.png](https://archive.blender.org/developer/F7549338/blender_2019-06-26_16-13-22.png) I've tried making the cube walls thick, or adding large objects on other side of the wall. But the problem persists. I know there are many limitations of eevee that can cause light bleeding. But this is persistent, leading me to think it's a bug.
Author

Added subscriber: @AndrewPrice

Added subscriber: @AndrewPrice

Added subscriber: @filibis

Added subscriber: @filibis

Added subscriber: @muratagawa

Added subscriber: @muratagawa

Added subscriber: @raitz

Added subscriber: @raitz

Added subscriber: @moisessalvador

Added subscriber: @moisessalvador

Contact shadows are screen space. They have the typical limitations of the other screen space things like AO and reflections. The thickness of the wall behind doesn't exist as far as screen space is concerned. I barely use them because of that and other limitations with thin object.

Do you want proper watertight shadows with real contact hardening and area penumbra? What I like to do is go to the Shadows panel in the render properties and change ESM to VSM, increase the cube size for better precision, and turn on high bitdepth and soft shadows. Then I go to each lamp, turn Softness to 0, since I'm using real soft shadows now. And turn bias to 0 and bleed bias to 0.5 or more. These are the closest to raytraced shadows you will get. And adding thickness to walls works with this method. You can still combine this with screen space contact shadows too

Contact shadows are screen space. They have the typical limitations of the other screen space things like AO and reflections. The thickness of the wall behind doesn't exist as far as screen space is concerned. I barely use them because of that and other limitations with thin object. Do you want proper watertight shadows with real contact hardening and area penumbra? What I like to do is go to the Shadows panel in the render properties and change ESM to VSM, increase the cube size for better precision, and turn on high bitdepth and soft shadows. Then I go to each lamp, turn Softness to 0, since I'm using real soft shadows now. And turn bias to 0 and bleed bias to 0.5 or more. These are the closest to raytraced shadows you will get. And adding thickness to walls works with this method. You can still combine this with screen space contact shadows too
Member

Added subscriber: @lichtwerk

Added subscriber: @lichtwerk
Clément Foucault was assigned by Philipp Oeser 2019-06-26 13:08:08 +02:00
Member

Added subscriber: @fclem

Added subscriber: @fclem
Member

@fclem: does this count as known limitation?

@fclem: does this count as known limitation?

Changed status from 'Open' to: 'Archived'

Changed status from 'Open' to: 'Archived'

Known limitation. Hopefully one day we will have raytraced shadows.

Known limitation. Hopefully one day we will have raytraced shadows.
Sign in to join this conversation.
No Label
Interest
Alembic
Interest
Animation & Rigging
Interest
Asset Browser
Interest
Asset Browser Project Overview
Interest
Audio
Interest
Automated Testing
Interest
Blender Asset Bundle
Interest
BlendFile
Interest
Collada
Interest
Compatibility
Interest
Compositing
Interest
Core
Interest
Cycles
Interest
Dependency Graph
Interest
Development Management
Interest
EEVEE
Interest
EEVEE & Viewport
Interest
Freestyle
Interest
Geometry Nodes
Interest
Grease Pencil
Interest
ID Management
Interest
Images & Movies
Interest
Import Export
Interest
Line Art
Interest
Masking
Interest
Metal
Interest
Modeling
Interest
Modifiers
Interest
Motion Tracking
Interest
Nodes & Physics
Interest
OpenGL
Interest
Overlay
Interest
Overrides
Interest
Performance
Interest
Physics
Interest
Pipeline, Assets & IO
Interest
Platforms, Builds & Tests
Interest
Python API
Interest
Render & Cycles
Interest
Render Pipeline
Interest
Sculpt, Paint & Texture
Interest
Text Editor
Interest
Translations
Interest
Triaging
Interest
Undo
Interest
USD
Interest
User Interface
Interest
UV Editing
Interest
VFX & Video
Interest
Video Sequencer
Interest
Virtual Reality
Interest
Vulkan
Interest
Wayland
Interest
Workbench
Interest: X11
Legacy
Blender 2.8 Project
Legacy
Milestone 1: Basic, Local Asset Browser
Legacy
OpenGL Error
Meta
Good First Issue
Meta
Papercut
Meta
Retrospective
Meta
Security
Module
Animation & Rigging
Module
Core
Module
Development Management
Module
EEVEE & Viewport
Module
Grease Pencil
Module
Modeling
Module
Nodes & Physics
Module
Pipeline, Assets & IO
Module
Platforms, Builds & Tests
Module
Python API
Module
Render & Cycles
Module
Sculpt, Paint & Texture
Module
Triaging
Module
User Interface
Module
VFX & Video
Platform
FreeBSD
Platform
Linux
Platform
macOS
Platform
Windows
Priority
High
Priority
Low
Priority
Normal
Priority
Unbreak Now!
Status
Archived
Status
Confirmed
Status
Duplicate
Status
Needs Info from Developers
Status
Needs Information from User
Status
Needs Triage
Status
Resolved
Type
Bug
Type
Design
Type
Known Issue
Type
Patch
Type
Report
Type
To Do
No Milestone
No project
No Assignees
7 Participants
Notifications
Due Date
The due date is invalid or out of range. Please use the format 'yyyy-mm-dd'.

No due date set.

Dependencies

No dependencies set.

Reference: blender/blender#66139
No description provided.