I’ve been trying for a few days to get a 4 channel splatmap into UE4 (RGB + Alpha). When I import the resulting PNG the alpha channel seems to be applied to each of the RGB channels and then adds lines where the alpha is.
I have managed to get this working by creating two separate images (RGB in one, Alpha in another) then bringing the RGB into Photoshop, adding an Alpha channel, pasting my alpha into that channel, and saving as PSD to import into UE4 but this adds extra steps to the workflow. Am I doing something wrong with my WM splat export or my UE4 import settings for the PNG?
This is unique to the PNG importing process. You just need to use another image format such as TGA when saving the splat map out of worldmachine.
The above step is called “Dilation” and is actually done to try and make edge bleeding artifacts better for alpha sprites. It’s not a very good dilator as you can see, and in your cause it will obviously just screw things up since the alpha isn’t really the alpha.
My world machine export options are PNG, TIFF and BMP so since UE4 doesn’t support TIFF and BMP doesn’t seem to have alpha’s I will stick to my current workflow.
It shows TGA output for Heightfields, but not for Bitmap Output which I am using for the splatmap. Unless I need a version newer than 3.0.dev3. I’ll have to check.
I also managed to output TIFF 8-bit per channel then convert that to 32bit TGA.
