   Normals at block edge problem
  HelloI am making a terrain using blocks, each block is represented by a texture in the GPU.The problem is to get the normals to match at the edges between blocks. The normal computation is done in the GPU by using rendering to FBO. Problem is I can not get the texels from the neighbouring blocks at the edge! I could sample those textures as well in the frag shader but It is difficult since everything is in a quad tree..so finding the neighbour block is not always easy.Any suggestions ?   