First thing first, the most important part is to properly configure Maya or 3Ds Max to make it easy when importing meshes into UDK, in this case I’ll be going through the Maya setup as it is what I’m using.
First of all we have to change the default up axis (Y) to the one expected by UDK (Z) in addition to making sure that the linear scale is set to centimeter, this can be done by accessing the windows>setting/pref>pref window. There under settings the up axis should be set to Z and the linear to centimeter.
After that we can fix the grid under display>grid, the default grid has 12 units length/width and has lines every 5 units with 5 subdivisions. The UDK editor has it a bit different, here the grid snaps to a power of two scale, meaning; 1,2,4,8,16,32,64,128,256,512,1024 and so on. To make Maya behave in the same way we can set the length/width to 512 units, grid lines every 512 units and 64 subdivisions.
With this you will get a snap point every 8 units. Note that you can also use 32 subdivisions, this will give you snap points every 16 units instead, 16 will give you every 32 and so on.
Also note that UDK has a different length unit, uu (unreal unit). Each 1uu is roughly equal to 2cm and an average character is 96uu tall.
Despite this being something very simple to fix it’s incredibly important, especially for us as we are working with creating modular tiles that can be reused to create more content. If the grid isn’t exactly correct or if the models aren’t placed correctly it will be impossible to use the tiles as we want to. Thus, in this project the grid is our god.