[SOLVED] Texture atlas has visible seams but it should not

Hello there fellow users!

I need your help and judgement with the following issue:

I have a 128x128 pixel texture. I have a mesh that is a flat quad but if you look at it in wireframe mode it consists of separate quads (like a minecraft terrain without greedy meshing). So each face is mapped to the texture (actually two triangles).
I use this texture on the mesh with a material and it looks perfect. The texture itself is seamless so it is easily tileable.
However, if I use a texture atlas, there are visible seams, itā€™s like the other textures I have added to the texture atlas are bleeding over just enough to be there visible seems.

Has anybody experienced this issue? How to resolve this?

Here is a picture of what Iā€™m talking about. Color is different because the lighting is different (itā€™s two separate projects using the same set of textures).

Edit: typos and clarification

You have one of two choices:

  1. set the min and mag filters to ā€œnearestā€ so that you get blocky pixelated style textures like minecraft.
  2. create a border between all of the ā€˜cellsā€™ to give gaps in between for the min/mag bleed to have proper color to sample.
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Hey pspeed!

Thank you for replying. Gonna try these out. Questino about the second suggestion: what do you mean exactly to create a border? On the mesh itself? Or on the texture?

I tired your first suggestion, it worked beautifully! Still curious about what did you mean by the second suggestion.
minmagfilter

I think he means to do this:

Picture shamelessly taken from google images.

Here is an example of my texture map (automatically generated). Here you can see the main textures and also the borders that prevent mipping problems highlighted in red. Those sections in general arenā€™t shown anywhere but when mipping causing bleeding itā€™s those borders that bleed in not the neighbouring texture

image

For the borders, itā€™s also common to partially repeat the texture instead of stretching itā€¦ at least for repeating textures.

Thank you guys! Now I understand.

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Hi!

I learned here that TextureArray is very good alternative to Atlas / texture map.

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Yes, i also like TextureArray too, but it require same sizes and formats of textures, also GLSL 4+ as i remember. I seen some Atlas maps with different texture sizes.

There are probably more differences - so not everyone use it as alternative.

  1. TextureArrays are not available on older versions, nothing can be said about that. is a limitation.

  2. In my example, I use square textures for the floor and oblong ones for the walls. You can use multiple arrays with different sizes.

  3. For tiny accessories, theoretically, a texture of the array itself can still be a mini atlas.

  4. With closed textures I can use repeatable mode: If the panel is e.g. 3 x 3 large for a area, then I do not define the TexCoord from 0fā€¦1f but from 0fā€¦3f in size. Finished. I donā€™t get closed textures in the atlas.