Making height maps in Blender
This tutorials shows how to make a height map (a picture with darker colours for low parts of the mesh and brighter colours for high parts of them mesh) from an existing mesh in Blender. After making the height map, you can apply it to your texture to give it sense of volume and/or use it to create the normal map.
Making height maps in Blender
The steps to follow are:
- Make the mesh UV map
- Set the Shading settings
- Set the Baking settings
- Bake the height map
Make the mesh UV map
First of all your mesh needs to have a UV map for this technique to work. If you need to make it, you can follow the guidelines given in these tutorials:
Split the main window in two and select the UV/Image Editor in the right window.
Set the Shading settings
Go to the Shading panel (select the corresponding icon or press the F5 key) and then go to the World buttons subpanel as shown in picture Shading settings.
In the World tab, change the default ambient colour (black), to a light yellow:
- Set the red ambient light (AmbR slider) to 0.9
- Set the green ambient light (AmbG) to 0.9
- Set the blue ambient light (AmbB) to 0.8
In the Ambient occlusion tab (Amb Occ):
- Press the Ambient Oclussion button. This will display other options
- Select the method from the drop-down box: Raytrace or Approximate.
- Select the sample generator option from the second drop-down box. The options available will depend on the method you've selected first. I use Raytrace and Constant QMC, but you can try the other methods/sample options available and see which one works best for you.
- Set the number of Samples: the higher this number the less noisy the height map will be, but also the more time it will take it to Blender to generate it. I find that a number of Samples of 12 is good enough, but again, you can use any other value.
- Press the Both button to darken and lighten the image at the same time: doing this the height map will have more contrast between dark and light areas.
Set the Baking settings
Now go to the Scene panel (select the corresponding icon or press the F10 key) and then go to the Render buttons subpanel as shown in picture Baking settings.
In the Bake tab:
- Press the Ambient Occlusion button: this will indicate Blender that you want to generate a height map.
Bake the height map
Now, still in the Bake tab, press the big Bake button. You'll see that Blender starts drawing a new picture in the UV/Image Editor window as shown in picture Height map. Wait until Blender finishes painting it (the time required will depend on the number of samples you've selected: the higher the number of samples the slower the process will be).
Save the height map by selecting, in the UV/Image Editor window, the Image -> Save as option from this window menu.
Once you've saved it, you can open it in GIMP or any other image editor and use it to improve your mesh texture or create its normal map.