Maya 2016 Multi-Tile Seamless Bake Workflow

This is all assuming you have a model that is broken up into more than one UV space, have the texturing, high and low poly complete.

1 – UV map the low poly and make sure that there is little to no stretching the model

2 – Combine the mesh into one, merge verts, and smooth edges (hard edges will create a visible divide with the normal map, so don't harden the edge unless you specifically want this)

select all in Object Mode - Combine, select all in Vertex Mode – Merge Verticies, select all in Object Mode - Mesh Display – Set to Face, select all in Object Mode - Soften/Harden – Soften Edge.

3 – Select the entire models UV shells and unfold all of the UV shells at the same time so that they are all the same resolution. This will stop any seams from being noticeable in the texture.

4 – Sort the shells into a 0...1 space, ensuring that each shell is centered in its own space (whether it be a quarter or eighth or more of the 0...1)

5 – Bake the complete model at a larger resolution than the end maps you want (if you want 8k maps, then bake a 16k if the shells are broken up into a quarter)

6 – In the UV editor select View → Grid Options and change the length and width to 10 and grid lines every 1 unit. This will make it so that every square is a UV shell.

7 – Using a UV manipulator script to resize the UV shells (like the one here http://www.creativecrash.com/maya/script/uv-manipulator) you can resize each shell to take up one UV shell each. If the bake was 16k for example and you have got a UV shell in each quarter of the bake, then you want to use the UV manipulator to make each shell twice as large, so that they all take up one 0...1 space each. To center to UV shells perfectly you need to select the shell and snap to the center of the 0...1 space (this should line up as in step 4 you have made the center of each shell centered).

8 – Now you just need to name your maps, the convention I use is diffuse_x0_y0, normal_x0_y0, occlusion_x0_y0 etc, with x0 and y0 relating to coordinates.

9 – In photoshop you also need to break up your larger map into smaller maps.

To do this I used Image – Canvas Size – and changed the anchor to the corner where my first shell was and broke it up that way.