Exporting and importing normal maps and lit sprites

You can export normal maps from the toolbar or the menu. SpriteIlluminator lets you choose export settings during the first export — if you want to change the settings later use Export normals as … in the Files menu.

Exporting normal maps

SpriteIlluminator: Export normal maps

The normal maps are placed in the same directory as the sprites with a suffix (_n). You can select a different output directory or suffix in the dialog.

Transparent background

Use this if you want to copy the transparency from the original sprite to the normal map. This has no practical use and makes the output files usually a bit bigger but looks nice :)

The color information in the pixels is the same as in the case with solid background — even in the transparent pixels.

Normal mapped sprites with solid background.
Normal mapped sprites with transparent background
With solid background
With transparent background.

Inverted axes

Some game engines require the y-axis in the normal maps to be inverted. You can do that by setting Invert y-axis in the output dialog.

Normal mapped sprites with transparent background
Normal mapped sprites with transparent background: Y-axis inverted
Default axis
Inverted axes

Z-Axis (Encoding)

In versions prior to SpriteIlluminator 2.1.0, the full 8-bit range (0–255) was used to encode the Z-axis of the normal map. This allowed for high precision when mapping values from 0.0 to 1.0, but required custom shaders to interpret the data correctly. (Z-Axis: 8-bit, requires shader support)

Starting with SpriteIlluminator 2.1.0, the Z-axis is by default encoded using only the upper half of the byte range (128–255). This matches the convention used for the X and Y axes and ensures better compatibility with standard shaders. (Z-Axis: 7-bit, best compatibility)

For backward compatibility, existing projects created with older versions will continue to use the 8-bit mode. New projects default to the 7-bit encoding.

You can switch between encoding modes via the Export normals as... dialog.

Exporting lit sprites

Use the menu or toolbar to export lit sprites as a preview. The export uses your current light settings. Here are some examples what you can export:

Sprite light effects with normal maps: Yellow light
Sprite light effects with normal maps: White light
Sprite light effects with normal maps: Blue light
Yellow light from above
White light
Blue ambient light,
red light from below

Exporting gif animations

You can also export animated GIFs using:

Importing normal maps

Use the menu Edit / Import normal map… after selecting a sprite to import an existing normal map.

Normal maps with the standard y-axis are supported. The normal map must have the same size as the sprite.