Downloaded a texture with blurry edges? Don't panic! It's deliberate.
Artists and 3D software prefer textures that have a 1x1 aspect ratio. They’re easier to manipulate, tile and use without altering any UVs. That’s why Poliigon uses a process common in game development known as Texture Dilation. Which "bleeds" the edge of the texture to fill the rest of the space.
Below we explain how to remove this dilation and also provide a longer explanation on what it is and why it's necessary.
How to remove Texture Dilation in Photoshop
How to remove Texture Dilation in your 3D software
What is Texture Dilation
Texture Dilation is a process common in game development which "bleeds" the edge of the texture to fill the rest of the space to maintain a 1:1 aspect ratio.
This is an example of a texture with Texture Dilation applied:
Ideally we'd always provide 1:1 aspect ratio textures without dilation but unfortunately, the real world is rarely so convenient. Most subjects look like this:
So typically, part of the texture processing step involves forcing a texture like this into a square 1:1 ratio. Which means cropping in (subtracting from sides or top) or infilling (duplicating information).
The final texture:
These approaches work great for subjects that are uniform and repetitive.
But for textures with distinctive, unpredictable patterns duplication isn’t possible without seams. Our Marble slab scans are the perfect example of this.
And so we Texture Dilation which "bleeds" the edge of the texture to fill the rest of the space.
In essence, this gives you all the benefits of a 1x1 texture but without losing or duplicating information.
But why dilation at all? Why not just a black background?
Black or transparent parts of the image can cause issues when a game engine downscales textures (mipmapping) on a UV mapped mesh.
Image source: Adobe Substance article for more example.
Dilation ensures that any errors in the UV mapping aren’t as readily noticeable.
That said, we know that not everyone is using textures for games, and therefore won't find the dilation helpful. So if you want to remove it from your texture read our guides above.