The image format only matters on disc space.
In memory all textures are converted to the format the GPU supports.
I do not think the image format influences visible seems.
Why are there visible seams?
The described problem with the seams has a quite simple reason.
Usually only the texture pixels inside the UV-face (including the edges) are used to draw the rendered face.
But the texture is not used directly. Before it is used as texture it is processed by the OpenGL mid-map filter. The default is to blur/anti-alias the texture. A side effect of this is that the color of a texture pixel is mixed with the color of it’s surrounding pixels.
On the edges the surrounding pixels are not all part of the UV-face. Therefore the rendered face can get color information from outside the UV-face (e.g. from a black border).
Just want to provide some background information. I think it is important to know about that. Micah your solution is absolutely fine.
I think it is worth a resource.
You might want to change the title of the thread as it does not only belong to characters (edit top post - advanced mode). It belongs to any object with textures. E.g. “Avoid seems in textured objects”.
.Jpeg and mip mapping!??
So mip maps in BGE are calculated in real time, rather then saving them beforehand?
Im not very experienced in blender game engine or game engines in general, but the game engine I previously worked with required that you stored the mip maps within the texture itself beforehand, fx as a .DDS texture.
So im wondering if you know whether theres actually benefit in using an image format that stores mip maps within in BGE?
(Also for those reading this and dont know exacly what I am talking about read this and look at the images)
If you want a completely seamless texture, the best way is to make another UV layer and then unwrap the texture again, but avoiding the original seams. Now bake your original texture on to a new UV sheet and set the border in bake to about 12. This will leave a border of pixels around each UV island which are the same as the neighboring pixels. You can also go back and clean up your original seams by using a blur or clone tool where they don’t match well.
With “Texture Paint” you set the margin with the “Bleed” parameter:
<T> to toggle tool options
I recommend at least a margin of 4. You might wan to check the texture at various detail levels. Be aware the “seam” effect increases with zoomed out (small model) view rather than zoomed in (large model).
This is what I do for my baking. After creating seams UV unwrap with a margin of 0.08. Go into the uvw editior and select the border of each island and scale it up so that the edges aren’t packed too closely. Bake the Ambient occ or other map with a margin set to 5 px. For Ambient occ I also turn on normalised so ugly artifacts and noise will be less visible.
After baking apply the bake image with shadeless material to check for seams … if they still show up. Easy fix! Go back to your UVW and scale your outer edges back in to where they were before! Fixed!
Additional notes :
Also before baking I would add a subdiv modifier to make sure edges of my model’s tesellation don’t show up, however this will require you to model carefully as subdiv modifier may change the shape and outline of your model alot if not done correctly.