Cycles Normal Bake problem #40023

New Issue

Adriano Oliveira · 2014-05-04T18:02:50+02:00

Adriano Oliveira commented

2014-05-04 18:02:50 +02:00

System Information
Windows 8.1 64 / Nvidia 560 ti 2gb

Blender Version
Broken: 2.70.5 a1ba57a

Short description of error
Cycles Bake normal (tangent or object) inconsiste with BI Bake.

Ortogonal extruded faces produces strange normal angles (BI is correct):

File:
bake.blend

**System Information** Windows 8.1 64 / Nvidia 560 ti 2gb **Blender Version** Broken: 2.70.5 a1ba57a **Short description of error** Cycles Bake normal (tangent or object) inconsiste with BI Bake. Ortogonal extruded faces produces strange normal angles (BI is correct): ![bake-normal.jpg](https://archive.blender.org/developer/F86911/bake-normal.jpg) File: [bake.blend](https://archive.blender.org/developer/F86913/bake.blend)

Adriano Oliveira commented

2014-05-04 18:02:50 +02:00

Changed status to: 'Open'

Dalai Felinto was assigned by Adriano Oliveira

2014-05-04 18:02:50 +02:00

Adriano Oliveira commented

2014-05-04 18:02:50 +02:00

Added subscriber: @AdrianoOliveira

Adriano Oliveira commented

2014-05-04 18:18:52 +02:00

It dosn't happen from a plane to other, but it does form a cube to other...
It seams related to the way projection is calculated.

It dosn't happen from a plane to other, but it does form a cube to other... It seams related to the way projection is calculated.

Dalai Felinto commented

2014-05-05 05:01:59 +02:00

Added subscriber: @AndyDavies-3

Dalai Felinto commented

2014-05-05 05:01:59 +02:00

@AndyDavies-3 could you do me a great favour and bake this in xnormals so I can use as comparison?

Andy Davies commented

2014-05-05 05:56:54 +02:00

Hey guys,

What you are seeing is correct (if you are using a cage) and xNormal has the same issue.

It's skewing from the bake because the geometry is coarse (very low poly). When baking with a cage the normals are averaged across the length of the surface which can cause the skewing you see here. The only fix is to either use hard edges (which is why BI works because it cant bake without hard edges) or add support loops close to the edges of the mesh which controls the projection better.

http://download.blender.org/documentation/bc2013/andy_davies_Normal_mapping_for_games_and_realtime_content.pdf - Page 51

It's also why projections in closer to the centre of each face show less skewing. :)

Hey guys, What you are seeing is correct (if you are using a cage) and xNormal has the same issue. It's skewing from the bake because the geometry is coarse (very low poly). When baking with a cage the normals are averaged across the length of the surface which can cause the skewing you see here. The only fix is to either use hard edges (which is why BI works because it cant bake without hard edges) or add support loops close to the edges of the mesh which controls the projection better. http://download.blender.org/documentation/bc2013/andy_davies_Normal_mapping_for_games_and_realtime_content.pdf - Page 51 It's also why projections in closer to the centre of each face show less skewing. :) ![test_normals.jpg](https://archive.blender.org/developer/F86962/test_normals.jpg) ![test_xn_cage_normals.jpg](https://archive.blender.org/developer/F86963/test_xn_cage_normals.jpg)

Adriano Oliveira commented

2014-05-05 17:39:42 +02:00

Ok, Fair to me.

But for the sake of compatibility, wouldn't it be batter to mantain the same logic cyclces-BI bake?

Ok, Fair to me. But for the sake of compatibility, wouldn't it be batter to mantain the same logic cyclces-BI bake?

Andy Davies commented

2014-05-06 06:35:36 +02:00

Yes, it would be nice if both BI and Cycles had the ability to use cages as they are a superior way to bake.
Uniform ray distance has so many issues when it comes to baking with hard/sharp edges. :)

Yes, it would be nice if both BI and Cycles had the ability to use cages as they are a superior way to bake. Uniform ray distance has so many issues when it comes to baking with hard/sharp edges. :)

Bastien Montagne commented

2014-05-06 15:45:57 +02:00

Added subscribers: @dfelinto, @mont29