In my project I am exporting a mesh from Blender 2.63a which uses a UVSphere. The UVSphere has UV coordinates applied, and I need tangents and binormals generated on the export so I can apply a normal map in my shader.
I can successfully export this into PVRShaman as long as the UVSphere has 32 or less longitudinal segments. If I increase the number of segments of the UVSphere to 64 or even just to 33, then I get the following error on export:
"Tangent-space generation failed due to too many split vertices."
I can have as many "rings" (latitudinal lines) on the UV Sphere as I like, but I cannot increase the "segments" (longitudinal lines) above 32.
I performed a few experiments and it only happens if I select "smooth shading" in Blender. If I leave the model "flat shaded" then I can have 64 segments with no issues. But I need a smoothed shaded model.
I have been working with this limitation over the past few months, while I concentrated on developing the rest of my shader code, but I am getting to the point now where I need to increase the number of segments.
I just downloaded the new version of the PVRSDK & Tools - very nice btw :) and I ran my tests again this morning with the same results.
Any help you can give is much appreciated,