Down with the flu today… so bear with me.
0.0 - 1.0 this is the full width or height of whatever image you are using as a texture.
1f/8f would give you 0.125f or an 8th of the image’s width or height
If you have 9 verts across your grid… the texCoords .x would look like:
Each vert increases by 0.125f (i.e. 1/8th of the image’s width)
If you want to know what a single pixel of your image represented in texCoords would be, you would do the following:
x = 1f/imageWidth;
y = 1f/imageHeight;
As for splitting up the floor (or have multiple verts through the mesh), this will help with more accurate lighting if you use Vertex Lighting.
For you example, where you are unsure of the config of the mesh, you’ll likely want to break it into the smallest component. In your case it would seem like wu would be the thing. So 1 world unit = 0.0 - 1.0 texCoords (if you are using tiling… which you likely will as the other option will just distort your texture).
As for texCoords going over 1.0… they can, but you have to set the wrap mode of the texture to repeat… Example using 5 verts across a grid tiling the image:
This would tile the image 4 times across the grid.
All the examples above are only using x… same applies to the y coords as well.