| Bastien Montagne (mont29) |
| maylog (maylog) | |
| Oct 10 2018, 9:52 AM |
| Bastien Montagne (mont29) |
| Brecht Van Lommel (brecht) |
| Clément Foucault (fclem) |
| maylog (maylog) |
System Information
Operating system and graphics card
Blender Version
Broken: 2.80 Alpha2 2018.10.09
Worked: (optional)
Short description of error
Exact steps for others to reproduce the error
Based on a (as simple as possible) attached .blend file with minimum amount of steps
There is no problem when opening with version 2.79.
I recorded a video
This is the problem scene file
It is not just a drawing issue. The edit mesh normals is all wrong and the texture is NOT mapped correctly.
The edit UVs are selectable at their displayed position and editable so it's not a display problem (since selection and edition are not using OGL).
And since the same file is read correctly by 2.79 I think it might be something wrong in the version update of the mesh data.
Ok so it seems that the drawing code is somehow corrupting the data. If you load the file and go into edit mode without a 3D view opened the UVs are displayed correctly.
But If you go into edit mode with a 3D view opened, then the UV data is being corrupted. The normals of the mesh are also not correct.
EDIT: After further investigation it's caused by the auto smooth option on the mesh.
The corruption happens when mesh_render_data_create_ex is called with types MR_DATATYPE_LOOP and the mesh uses the auto smooth feature. The culprit function is bm_mesh_loops_calc_normals().
After more investigation it seems that this patch fix this issue. So I guess it's a problem about clnor not being correct.
@Bastien Montagne (mont29) Since you wrote most of this function assigning to you.
diff --git a/source/blender/bmesh/intern/bmesh_mesh.c b/source/blender/bmesh/intern/bmesh_mesh.c
index 8833564e486..aa1dbc1379b 100644
--- a/source/blender/bmesh/intern/bmesh_mesh.c
+++ b/source/blender/bmesh/intern/bmesh_mesh.c
@@ -915,8 +915,10 @@ static void bm_mesh_loops_calc_normals(
while ((clnor = BLI_SMALLSTACK_POP(clnors))) {
//print_v2("org clnor", clnor);
+ #if 0
clnor[0] = (short)clnors_avg[0];
clnor[1] = (short)clnors_avg[1];
+ #endif
}
//print_v2("new clnors", clnors_avg);
}