Blender Texture Basics:
Base Color, Roughness,
and Normal Maps

Blender lets you set a surface with numbers alone: pick a color in Base Color, adjust the shine with Roughness. Try to build a wooden table that way and you get the color of wood, but no grain.

Set color and shine with numbers and the entire surface ends up looking identical everywhere. The surface of real wood isn't uniform: the color is deeper in some places, it catches the light differently in others. No single number can describe that.

Whether the wooden table we're about to build reads as real comes down to three things: how light hits it, its shape, and the surface. We set up the light in the previous article, with an HDRI environment image. The shape is fine as it is, since the tabletop is a flat board.

That leaves the surface. Textures are what you use to create it — wood grain, fabric, and the like, applied as images.

First you need the images. We'll get them from Poly Haven, the same site we used for the environment image last time.

Poly Haven releases its assets under CC0, a license that requires no credit and permits commercial use.

There are plenty of other texture sites, but free doesn't always mean unrestricted. Some assets are personal use only; others require a credit. Check the license, and if it says CC0, you can use it without worrying about what for.

Search for wood table and you'll get a row of wooden table textures. This article uses "Wood Table Worn," but pick whichever you like.

Poly Haven lets you decide what goes in the download before you start it. Click the icon in the middle of the download button to open the file format menu, then choose "ZIP" to bring up a list headed Choose ZIP contents:.

By default this includes a .blend file and images we won't be using. Narrow it down to these three.

Set the resolution to 1K. Untick every other row, Blend and Gltf included.

Unzip the download and you'll find the three images inside a folder named textures.

In the filenames, diff is the color, nor_gl is the bumps, and rough is how it catches light. diff is short for diffuse, though the socket you'll connect it to is called Base Color — the texture site and Blender use different names for the same thing.

nor_gl and rough come as EXR, an extension you may not have seen before. Blender reads it without any extra steps.

We'll start with the color image, the first of the three.

Switch to the "Layout" tab at the top of the screen and add a plane with Shift + A, then "Mesh" then "Plane." If you're continuing from the previous article, add it to that file; if you're starting here, a new file with a cube or similar in it works fine.

Press S to scale it up to something table-sized — the screenshots use a scale of 5.

Next, press Ctrl + A and choose "All Transforms." This locks in the object's size — the same step we took in the previous article before giving the glass its thickness.

Switch the tab at the top to "Shading" to open the Shader Editor we used last time.

The plane has no material yet, so click "New" to create one. Two nodes are placed automatically: the Principled BSDF and the Material Output.

Add an image texture node with Shift + A, then "Texture" then "Image Texture."

Click "Open" inside the node and load wood_table_worn_diff_1k.

Then connect "Color" on the Image Texture to "Base Color" on the Principled BSDF, the same way you connected nodes in the previous article: click a socket, drag, and drop on the socket you're connecting to.

The wood grain shows up.

You haven't told Blender where to put the image or how big to make it. The grain still sits neatly across the board.

That's because a plane comes with UVs already set up. UVs are the information that decides where on a surface each part of an image goes, and Blender's primitive shapes — planes, cubes, and the like — have them from the start.

It's often assumed the image won't appear unless you connect a Texture Coordinate node. On a primitive shape, it appears without one. Texture Coordinate becomes necessary when you want to adjust the scale or orientation of the pattern.

The grain is there. Move in closer, though.

The whole surface catches the light the same way, smooth and flat. The pattern of the grain is there, but it doesn't read as wood. What you have is a photo on a board.

Two more images go on top of this.

Time to connect the other two.

The diff image you've already connected was meant to be looked at — it's the wood grain you see. The two images coming up are not.

They look like images, but what's inside them is numbers. So you have to tell Blender they aren't color, which is what the Color Space setting is for. Images that hold color stay on sRGB; images that hold numbers go to Non-Color.

Leave a data image on sRGB and Blender corrects it as if it were color, changing the numbers that were recorded. The surface comes out wrong as a result.

Add another Image Texture with Shift + A, then "Texture" then "Image Texture," and load wood_table_worn_rough_1k.

Once it's loaded, change "Color Space" inside the node to Non-Color.

The dropdown opens with several entries marked "▶" near the top. Don't open those — Non-Color is further down the list.

With that set, connect "Color" on the Image Texture to "Roughness" on the Principled BSDF.

The look changes.

Where the surface caught the light uniformly a moment ago, it now varies. The areas where the finish survives are glossy; the areas worn back to bare wood have lost their sheen.

If Base Color decides what color something is, Roughness decides how it catches the light.

One image left. Add an Image Texture with Shift + A, then "Texture" then "Image Texture," and load wood_table_worn_nor_gl_1k. Set its Color Space to Non-Color, same as the roughness map.

This one doesn't connect directly, though. It goes through one node on the way.

Add it with Shift + A, then "Displacement" then "Normal Map," and connect things in this order.

Light and shadow appear in the grooves and the grain of the wood.

This image needs the extra node because the Normal Map node is what reads those RGB numbers back as direction. Skip it and Blender takes them as color instead. No error is raised, and nothing happens.

If the change is hard to make out, raise "Strength" on the Normal Map node — the screenshots in this article use 3.0.

Bear in mind that this only looks like relief. The geometry hasn't changed: view the board from the side and it's still flat.

Two images is all we added, and it's no longer the photo on a board we started with.

The Base Color image never changed from beginning to end. What changed is how that surface reflects light. Whether something reads as wood comes down less to the image itself than to the way light comes off it.

With three images in play, it's easy to lose track of what connects where — wiring the roughness image into Base Color, for instance.

When that happens, go back to Base Color on its own. Remove the roughness and normal links and you're back at the state from Building the table and applying one image. Reconnect them one at a time from there and you'll find where it went wrong.

The grain is applied, but nothing has been done about its scale yet. As it stands, a single plank reads wider than it would on a real table. Let's adjust it.

Picture a sheet of transparent graph paper laid over the surface, marked from 0 to 1. UVs are the information that decides which part of the image sits where on that sheet. A plane comes with UVs already, which is why the grain lined up neatly without you setting anything.

Move the UVs and the image looks different. What you're changing isn't the image itself — it's how the image is applied.

Add both with Shift + A: "Input" then "Texture Coordinate," and "Utilities" then "Vector" then "Mapping."

Connect them in this order.

Set X and Y under "Scale" on the Mapping node to 4.0.

The pattern gets smaller and repeats more often. You raised the number, and the image shrank.

That's because what you're scaling is the UVs, not the image. Stretch the UVs to four times their size and the image sitting on them becomes proportionally smaller, repeating across the board.

If you're not sure what number to use, judge it by how fine the grain looks.

Too low and the grain stretches out, making the board read as larger than it is. Too high and the grain gets so fine it starts to look more like fabric than wood. Compare it against the cup sitting on the table and stop where the grain looks about right.

Mapping adjusts more than size. Changing "Location" shifts the pattern, and setting Z under "Rotation" to 90 turns the direction of the grain.

We've been adjusting the pattern by moving UVs around. What we haven't done once, though, is UV unwrapping — the staple of texture tutorials. UV unwrapping is the work of building those UVs yourself.

For putting a pattern across a surface — wood, stone, and the like — not knowing how to unwrap won't hold you back. UV unwrapping becomes necessary when you need to decide which part of an image lands on which part of an object.

A label on a can, a print on a T-shirt, a character's face. When the artwork has a position it has to be in, that's when you unwrap.

Cylinders and spheres are the only ones marked "Mostly works," because parts of them take the image cleanly and parts of them don't. Here's the same wood grain from this article applied to a sphere.

The sides come out fine. The only trouble is at the poles, where the pattern collapses inward in a spiral. It isn't that you can't texture a sphere — it's that it breaks down at two specific points.

Even a plane will stretch its pattern if you change its proportions much.

When this happens, "Object has non-uniform scale" appears at the bottom left of the screen, telling you the object hasn't been scaled by the same factor on every axis.

Clearing that message won't fix the pattern, though.

Run Ctrl + A then "All Transforms" and the scale values return to 1 and the message disappears, but the pattern stays stretched.

That's because applying scale doesn't touch the shape of the UVs. They're already stretched, so short of rebuilding them, the grain stays that way.

The next article walks through how to rebuild them.

Note that more than one thing makes a pattern stretch: no UVs, distorted UVs, a different set of UVs in use, or an object whose size was never applied.

So when a pattern stretches, work through the causes in order before reaching for unwrapping.

If you applied an image and nothing shows, or everything came out black, work down these five checks.

If it looks right in Material Preview but goes black in a render, there isn't enough light. Check the environment image you loaded in the previous article.

In this article we layered three images to build a wooden surface.

If that felt like a lot to take in, these five points are enough to work with.

Next comes UV unwrapping, which is how you get "this artwork, right here" — the label on a can, the face on a character, anything where position matters. It's also where the stretched pattern we couldn't fix in this article gets sorted out.