Page MenuHome

GLSL Spotlight Bias Bug?
Closed, ArchivedPublic

Description

--- Operating System, Graphics card ---
Linux (LFS)
Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09)

--- Blender version with error, and version that worked ---
Blender 2.66a

--- Short description of error ---
possible spotlight bug ?
I was following this tutorial : https://www.youtube.com/watch?v=Jx830_W7MzY
and possibly discover a bug with spotlight : see this video I made : http://youtu.be/XsQZ4cKxTCk
I was animating the spotlight along y axis and you can see "extra" lighted area (under the window) showing in the video.

--- Steps for others to reproduce the error (preferably based on attached .blend file) ---
I will attach the blend file or you can follow the tutorial and recreate it yourself.
I haven't turn on halo or anything just simple default spotlight.
BTW, I have already try applying the solidfy modifer, still same problem.
The geometry is fairly simple and I have double checked all the normals.

Event Timeline

Reducing the `Bias` value of the lamp resolves the problem, but when rendering this works as expected.

This could be a bug in GLSL's use of the bias value?

Assigning to Brecht.

It's because GLSL only implements the "Classical" shadow buffer type, not "Classical Halfway". If you turn on the former for rendering you'll see the same issue. We only support a subset of the render engine features in GLSL, this is one such case. All I can suggest is to tweak the Bias value.

Brecht Van Lommel (brecht) changed the task status from Unknown Status to Archived.Apr 9 2013, 3:04 PM

Thanks, I try bias 0.01 and it looks fine now.