Also document that gl_FrontMaterial is no longer supported in Irrlicht 1.9 (this has been the case for a few years, I just never noticed this was changed as I never even knew that was possible in the past...). Will keep it that way is it's definitely going in the right direction (getting rid of legacy support and going towards OpenGL core instead),
git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6498 dfc29bdd-3216-0410-991c-e03cc46cb475
S3DVertexTangents also documents that it's passed as TEXCOORD1 and TEXCOORD2, but easy to miss, so added some comments to the hlsl shader.
Also not all materials work well as base materials.
git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@6452 dfc29bdd-3216-0410-991c-e03cc46cb475