Recently, I found my model has normal map seam when rendering in Unity with our custom shader.
And I try to use the Unity built-in shader to render it. The result shows that there's no seams. How strange? Soon I found that because of all UV of my models are symmetry. It means that half of my UV are flipped. Hence, the binormal of the half model has been reversed. (tangent basis is calculated by normal and UV, http://www.3dkingdoms.com/weekly/weekly.php?a=37)....
