How To Create Texture Maps In Gimp

You just modeled the perfect scene and the only thing left is texturing and lighting. You get some great textures from cgtextures.com and apply it only to find your image still doesn’t quite have that pop. The reason for this is, that an image texture is merely a flat projection on your model. It is the same as putting a picture on a wall the photo is only a flat projection. The texture needs some depth and definition. To give the texture what it needs is simple a matter of adding a few things to give it more realism.

Your texture needs a normal map, a specular map, and some displacement to give it the detail it needs to mirror realism. If you have gimp you have the power to generate these maps within that one little program. Gimp can generate normal maps ,bump maps, displacement maps, and even specular maps. You can do it pretty fast with some short and simple steps.

I use a normal map and spec map with my textures. I use the spec map for displacement so I only need to generate the two maps.     

Creating the Normal map In Gimp:

1. Open up your texture in Gimp

2. Select color scroll down to desaturate

1. Select filters scroll to normal map in the normal map tab just click ok.

Click file export, select your texture folder and click export and your normal map is ready to use.

Creating the Specular map In Gimp:

1. Open up your texture in Gimp

2. Select color scroll down to desaturate

3. Select colors scroll to levels

4. adjust the input levels towards the middle

Click file export, select your texture folder and click export and your spec map is ready to use.

 

Fyi

You may want to put your textures in a folder for example brick texture and place your textures in with names such as brick.jpg, brick_normal.jpg and Brick_spec.jpg. This way all your texture maps are in one place.

Bonus Time

Here we have a basic plane with a diffused texture

Now we add a mix shader and a glossy shader

Now we have this

Now if we add the spec map and a color mix node we will put the texture in the top , set the bottom to black and change the blend mode to multiply then  put that in the factor input of the mix shader.

Now we this

Now let select the specular texture and the color mix node duplicate it and place it in the displacement socket

you have this

Then we add our normal map as an image texture connect it to a normal map node the connect it to the normal input of the glossy and diffused shader

Which gives us  this result

On the left just a plain image texture on the right our better texture. Which do you prefer?

Additional Resources

The Secrets of Realistic Texturing

 

Introduction to Texturing with Cycles in Blender