The Normal Map is used to bring a lot more detail onto the mesh. A 3D model has already normals (imagine them like spikes on the surface) on every vertex. They stick out and define the shading of the mesh depending on the angle to a light source. If the normal faces the light source at an angle of 0° the surface there has the most light. If the angle is 180° the normal points away and the light source hasn't any effect on that vertex.
Normals can point in any direction, defined by X,Y,Z. In the Normal Map we can use the RGB channels for these values where every pixel of the map becomes a normal. With a 1024x1024px texture that makes over 1 Million additional normals we can influence the direction! See below what makes a The Sims 3 Normal Map special.
The Normal Map needs to be saved as DDS → DXT5. In the TSR Workshop the Normal Map can be found here:
- Mesh → DDS (first entry)
Standard Normal Map
- X → Red Channel (R)
- Y → Green Channel (G)
- Z → Blue Channel (B) (not used in example, see below why)
The Sims 3 Normal Map
- X → Alpha Channel (A)
- Y → Red, Green, Blue Channel (RGB)
Z is not used in TS3 Normal Maps.
How to create a The Sims 3 Normal Map
This mini-tutorial focuses on Photoshop but is probably mostly the same in GIMP too. See Plug-ins if a Normal Map plug-in is available for your image editing program.
Making the Height Map
This map can be often made from the Multiplier texture as this brings already a lot of height information with it. You can of course paint heights (mid-grey to white) and depths (mid-grey to black) yourself onto the map.
This example needs some more contrast to have a visible effect on the normal map.
Generating the Normal Map
Now the Normal Map filter is applied (don't change default settings):
- Filters → NVIDIA Tools → Normal Map Filter...
Arranging the Channels
The Red Channel (X) needs to be copied into the Alpha Channel.
If you don't have an Alpha Channel yet, create one by clicking on the little page icon.
The Green Channel (Y) goes into the Red and Blue Channel.
Unsure how to do this?
See Working with Channels for more info on this.
Final The Sims 3 Normal Map
The final The Sims 3 Normal Map looks like the example on the right. Save Normal Maps always as DDS → DXT5.
Normal Map Plug-ins
You probably have this already when you downloaded the DDS plug-in (Current Version). NormalMapFilter.8bf belongs to the folder: C:\Program Files\Adobe\Adobe Photoshop CSX\plug-ins\filter
Download the Windows 32-bit binaries. To install, extract the normalmap.exe file to your GIMP plugins directory usually located at:
Then extract the 3 dll files to your GIMP bin directory. This directory is usually located at: