Hi I was making a cubemap to use in a special ore vein but the game doesn't recognize my custom cubemap , for some reason it doesn't shows up .... it said invalid or something similar , I then saw the other cubemaps do not have alpha so I saved in dxt1 dds , b4 was dxt5 but still doesn't appear ... it seems to not recognize the mipmaps ...

why this?

Well for each of the six sides, in a vanilla cubemap the corresponding mips are loaded next to each side. When you then save it and create mipmaps it puts all 6 sides together, and the next mip level for all 6 sides together out to the right, and so on. Hard to explain without images, but I don't feel like taking images. I'll do it textually. ABCDEF are all 6 sides, and 123456 are the mip levels. So, left to right you have A1A2A3A4A5A6 then B1B2B3B4B5B6 and so on. When you save it back out again the format is A1B1C1D1E1F1 then A2B2C2D2E2F2 and so on.

What you need to do is select the "Cube Map" option before saving it back out. If you use the Nvidia plugin for Photoshop, it's the 2nd dropdown. The default says "2D Texture" and you select Cube Map instead from that dropdown list. If you use some other exporter, I am not sure if it has the Cube Map option.

Ok I understood the concept but not sure about the process to create the cubemap ?

can you describe it more precisely in steps ? Thanks a lot ...

1. save as DTX1 1-bit alpha (it wont save an alpha channel if you dont have one, dont select DTX1 'no alpha' or else it will save a blank alpha even if you dont have one)

2. select CubeMap in the drop down


make sure youre using an 'Environment Map' shader