• Products
  • Solutions
  • Made with Unity
  • Learning
  • Support & Services
  • Community
  • Asset Store
  • Get Unity

UNITY ACCOUNT

You need a Unity Account to shop in the Online and Asset Stores, participate in the Unity Community and manage your license portfolio. Login Create account
  • Blog
  • Forums
  • Answers
  • Evangelists
  • User Groups
  • Beta Program
  • Advisory Panel

Navigation

  • Home
  • Products
  • Solutions
  • Made with Unity
  • Learning
  • Support & Services
  • Community
    • Blog
    • Forums
    • Answers
    • Evangelists
    • User Groups
    • Beta Program
    • Advisory Panel

Unity account

You need a Unity Account to shop in the Online and Asset Stores, participate in the Unity Community and manage your license portfolio. Login Create account

Language

  • Chinese
  • Spanish
  • Japanese
  • Korean
  • Portuguese
  • Ask a question
  • Spaces
    • Default
    • Help Room
    • META
    • Moderators
    • Topics
    • Questions
    • Users
    • Badges
  • Home /
avatar image
0
Question by AnatolyDream · Apr 15, 2016 at 05:44 PM · unity 5shadershadows

Does Two-Sided mode for Cast Shadows affect performance?

Hi!

In Mesh Rendered component there is an option for Cast Shadows to be Two-Sided.

Here is some information about it: "Shadow rendering will turn off backface culling, even if object's shader has backface culling on. This means that single-sided objects (like a Plane or a Quad) will cast shadows, even if the light is behind them."

Do you guys know if this mode affects performance too much?

Comment
Add comment · Show 6
10 |3000 characters needed characters left characters exceeded
▼
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Viewable by all users
avatar image AnatolyDream · Apr 16, 2016 at 02:25 PM 0
Share

Nobody knows...?

avatar image Namey5 · Apr 17, 2016 at 10:27 AM 0
Share

I would assume so, seeing as it would render both faces for the shadow map.

avatar image AnatolyDream Namey5 · Apr 17, 2016 at 05:05 PM 0
Share

Do you have any tips on how to solve the problem with light leaking through object's UV seams? I've made sure there are no holes or any unconnected vertices in the model. I've found a lot of questions here about this light leaking problem here but nobody knows how to avoid it except for using Two-Sided mode for casting shadows or setting bias to 0 (which makes scene look worse, so the only way that works for me is the Two-Sided casting mode).

avatar image Namey5 AnatolyDream · Apr 18, 2016 at 12:12 AM 0
Share

Yeah, the leaks are a bit of a pain (especially if you spend a lot of time working with shaders like me), but if the two sided mode works for you, go for it. I just wouldn't use it on everything.

Show more comments

1 Reply

· Add your reply
  • Sort: 
avatar image
4

Answer by Allen0012 · Oct 28, 2017 at 05:47 PM

I'm sure you've found the answer to your question by now but I'm gonna leave my experience here for anyone who stumbles upon this question.

I ran a few test with a few thousand one sided quads to find the answer to this. Turns out performance-wise they are the same, "On" vs "Two Sided" have the exact same performance hit.

And it only makes sense, in the shadow projection calculation there's just the mater of surface normal vs light direction to decide whether or not to include that object, there is actually more instructions involved to check if a surface is one sided (and the dot of its normal with the light direction is greater than zero) to include it in the shadow calculation than just including it without any calculations..

I hope this makes sense.

Comment
Add comment · Share
10 |3000 characters needed characters left characters exceeded
▼
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Viewable by all users

Your answer

Hint: You can notify a user about this post by typing @username

Up to 2 attachments (including images) can be used with a maximum of 524.3 kB each and 1.0 MB total.

Welcome to Unity Answers

If you’re new to Unity Answers, please check our User Guide to help you navigate through our website and refer to our FAQ for more information.

Before posting, make sure to check out our Knowledge Base for commonly asked Unity questions.

Check our Moderator Guidelines if you’re a new moderator and want to work together in an effort to improve Unity Answers and support our users.

Follow this Question

Answers Answers and Comments

5 People are following this question.

avatar image avatar image avatar image avatar image avatar image

Related Questions

How to make a 2d shader with edge waves 0 Answers

Jelly Defense like Planet Lighting/Shading? 1 Answer

Issue with standard Unity 5 shader on ios8 1 Answer

XCOm Style Visibility Bubble Shader 0 Answers

How to change the reflection according to skybox-material? 2 Answers


Enterprise
Social Q&A

Social
Subscribe on YouTube social-youtube Follow on LinkedIn social-linkedin Follow on Twitter social-twitter Follow on Facebook social-facebook Follow on Instagram social-instagram

Footer

  • Purchase
    • Products
    • Subscription
    • Asset Store
    • Unity Gear
    • Resellers
  • Education
    • Students
    • Educators
    • Certification
    • Learn
    • Center of Excellence
  • Download
    • Unity
    • Beta Program
  • Unity Labs
    • Labs
    • Publications
  • Resources
    • Learn platform
    • Community
    • Documentation
    • Unity QA
    • FAQ
    • Services Status
    • Connect
  • About Unity
    • About Us
    • Blog
    • Events
    • Careers
    • Contact
    • Press
    • Partners
    • Affiliates
    • Security
Copyright © 2020 Unity Technologies
  • Legal
  • Privacy Policy
  • Cookies
  • Do Not Sell My Personal Information
  • Cookies Settings
"Unity", Unity logos, and other Unity trademarks are trademarks or registered trademarks of Unity Technologies or its affiliates in the U.S. and elsewhere (more info here). Other names or brands are trademarks of their respective owners.
  • Anonymous
  • Sign in
  • Create
  • Ask a question
  • Spaces
  • Default
  • Help Room
  • META
  • Moderators
  • Explore
  • Topics
  • Questions
  • Users
  • Badges