Edge Padding

A texture only has color where the UV islands are. Everything around them is empty. When the renderer filters a pixel near the edge of an island, it mixes in that empty space, and you get a dark outline along every seam. It gets worse on smaller mips, because the filter reaches further.

Edge padding copies each island edge color outward into the empty pixels around it, so there is something sensible to blend against. Nothing inside the islands changes, and the alpha channel is left exactly as it was.

How much padding do I need?

Enough to survive your smallest mip. A common rule is 2 pixels per mip level, so 16 px covers four mips comfortably. Padding is free at runtime, so it is better to overshoot.

Does it change my texture?

Only the empty pixels get written. Everything that already had color comes out identical, and so does the alpha channel.

Is this the same as dilation in Substance or xNormal?

Same idea and same result. The difference is that this works on a finished PNG, so you can pad maps you no longer have the source file for.

Related: ORM Packer · Tiling Checker · Channel Split

All tools

ORM Packer: Combine ambient occlusion, roughness and metallic maps into a single packed RGBA texture, with control over which map goes in which channel.

Tiling Checker: Preview a texture tiled 3x3 with the seams highlighted, plus a half-offset view, so visible edges and obvious repetition show up before the asset ships.

Material Preview: Preview albedo, normal and ORM maps together on a lit sphere or cube, without exporting into Unreal or Unity to check how a material looks.

Height to Normal: Convert a height, bump or displacement map into a tangent space normal map, with adjustable strength and a choice of DirectX or OpenGL output.

Combine Normals: Layer a detail normal map over a base one and keep the detail from both, instead of averaging them into something flatter than either.

Normal Strength: Scale how much a normal map bends the light, without rebaking it. Keeps the map valid instead of breaking it the way a contrast slider would.

Levels: Set the black point, white point, midtones and inversion of a roughness, AO, height or mask texture, with a live preview.

Flip Green: Invert the green channel of a normal map to switch it between DirectX and OpenGL, which fixes normals that light inside out.

Rough ↔ Gloss: Convert a roughness map to glossiness or smoothness and back, for assets moving between engines that expect one or the other.

Renormalize: Restore a normal map after resizing, blurring or compression has weakened it, without changing which way any of it points.

Material from Photo: Generate albedo, height, normal, roughness and AO maps from a single photo, as a starting point you then tune.

Seamless Maker: Turn a photo or texture into one that repeats cleanly, by shifting it by half and blending the mismatched edges away.

AO & Curvature: Get ambient occlusion, curvature and cavity maps out of a normal map, with no high-poly mesh and no baker, for edge wear and dirt masks.

Channel Split: Split a packed ORM, RMA or mask texture back into one grayscale map per channel, exported individually or as a zip.