BadDogSkyrim
commented
2 months ago Yes, probably colors should be on vertices. I don't think that was available when I implemented them. Face corners should be correct as long as all corners have the same colors. If they don't you should see a seam in Blender.
I think you're saying there's a bug where the vertex color value isn't the same on export as it was on import. I'm not sure what the problem might be, but I did accept a change having to do with calculating values that would show up correctly in the viewport, so there might be a bug there. But it will be about handling the color value, regardless of face corner color vs vertex color.
k5tQp2ET
VessperiaS
Currently modding Fallout 4 hairstyles. Noticed that after export mesh changes it's colors. The thing is hairstyles are colored by gradient texture that applies it's colors by vertex colors (the whiter the vertex color the lower color is taken from palette texture of hair colors). If color shifts a bit > you are getting almost completely different color on hairstyle since the numbers are very limited (5 shades per one hair color avaliable). Due to this problem of distorted colors on meshes that use gradients (in Fallout, these are not only hairstyles, but sometimes clothes and armor), the mesh can be severely damaged on export. For example, if the rgb value was 251,251,251 on the hair roots (the extreme available value for applying a darker color for hairs) > the vertexes have a darker color on export, below 251,251,251 > then the standard darker ginger hair color on the roots becomes completely different, since it takes an adjacent gradient from the hair color palette which is called "light brown" ingame.
This is very simple to replicate if you take male hairstyle's hairline (since it is informative to visual comparison), import to blender and export right after.
_Male Hair26Hairline.nif for example. Colors distorted, but but they do not go below 251,251,251, since the original mesh has maximum color values closer to 255,255,255. There are other meshes that have too low values for the correct appearance on export with PyNifly.
My guess that this might happen because of the type of element the color attribute is stored on - for now it is Face Corners. I may be wrong, but I've never heard of models storing colors this way in games. Most likely, the vertex should be specified as the type. Maybe on import vertex colors are distorted because they converts to face corners and it mixes the colors a bit.
If I try manualy convert the color layers to vertex type, the nif simply refuses to export and shows an error.
In addition, this whole color distortion problem has almost no effect on the alpha channel. Alpha affects transparency in the game, but in fact the problems are not noticeable because alpha uses the entire range of black and white values from 0 to 255.