Texture Creation
description
A guide to what Normal Map is and how to apply it to your textures.
keywords
normal, normals, map, maps, texture, textures.
Ok, time to show you how to make normal maps.
What the hell is a normal map?
A normal map is a RGB map that indicates to the engine the normals of each pixel. Red, Green and Blue indicates the X, Y and Z values to the engine. This give your model more details without adding polygons and using low resources. Note that in Half-Life 2, DX7 has no normal mapping at all, DX8 only on world, and DX9 on both world and models.
How do I make normal maps?
There's 2 ways to make normal maps. The first one uses a higher poly model and a plug-in in your 3D application. The second, which I prefer, only requires Photoshop. I'm going to show you the second way to make normal maps, since using a 3D application sometimes differs from a program to another.
First step is to download the NVIDIA Normal Map plug-in here. Install it and open Photoshop. Then load your texture you want a normal map for. Create a new layer over it.
To use the plug-in, you need to create a greyscale map of the height of your texture. More its white, higher it is. Darker will make a lower bump. Here's an example map. Look at the render below it, you'll see the dark parts made down bumps and the white parts made higher bumps.
GRAYSCALE MAP
GRAYSCALE MAP + NVIDIA NORMAL MAP PLUGIN
RENDER
The most common technique used on complex texture is to put the texture itself in greyscale using Desaturate function in Photoshop. But I don't recommend this technique since the colour of a texture does not always represents it's bump properties.
Hope this helps a bit.
Farles
