Imagination PowerVR SDK Blog

Tangents & Binormals not generated by PVRGeoPOD

pvrgeopod
pvrshaman

#1

Hi There,

I’m using the PVRGeoPOD Blender export.

I create a basic UV Sphere with all the standard defaults (i’ve also tried this with the torus mesh with same result). I then export with PVRGeoPOD.

I leave all the options as default (generate tangent space is ticked)

The Vertex Vector Format has Position, Normal, Tangent, Binormal (a0,a1,a2 ticked) and all the UVW0 to 7 are selected (a0, a1 ticked)

I’m not sure about the UVWx values (I assume they are texture coordinates) - I left them at their default values for the export

I haven’t added any textures in Blender as I was going to do all that in PVRShaman with materials.

After the export I open the result in PVRShaman - I see the geometry but when I open the Data Viewer screen there is no Tangent or Binormal data in the POD.

(i’ve tested this with Blender 2.61, 2.62 and the latest 2.63b versions)

Am I missing something obvious?

Thanks in advance for your help Smile

Andre.









#2


Hi,
 
The tangent space generation requires UV coordinates for calculating the tangents and binormals. By default, Blender doesn't create meshes with UV coordinates so I assume this is why it isn't working for you. If you add UVs to your mesh the generation should be successful. 
 
Thanks,
 
Scott

#3

Hi Scott, thanks for the help