BLMAP (File Format)

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The BLMAP (Binary Light MAP) filetype controls lighting mapping. It is always seen in the posteffect folder inside an U8. This file is not required for a track to load, as there is a default.blmap file inside Common.szs. BLMAP files control how the BLIGHT lighting reflects off a linked texture, determining how shiny a surface is. It does so by creating a spherical displacement map and a gradient. The type of gradient determines the drop-off from the fully illuminated side of the sphere to the ambient color. The generated 32x32 grayscale sphere-shaped texture then replaces the original.

File Format

File Header

The following table describes the LIGHT header.

Offset Type Description
0x00 String File magic. Always LMAP in ASCII.
0x04 UInt32 File size. Always 0x298 in MKW.
0x08 UInt8 Version. Always 00 in MKW.
0x0C UInt32 Unknown. Always 00 00 00 00.
0x10 Uint16 Number of LTEXs. Always 0x02 in MKW.
0x12 Byte[14] Padding.

Light Texture data (LTEX)

The first object starts at 0x20. These addresses are relative to the start of the object. The object contains a list whereby each entry acts as a shader stage where the linked light is applied. Each entry sets its own gradient type. Each entry therefore applies permanent simulated lighting to the object with the given texture.

Offset Type Description
0x00 String Section magic. Always LTEX in ASCII.
0x04 UInt32 Section size. Always 0x13C.
0x08 Uint8 Version. Always 00 in MKW.
0x09 Byte[3] Padding
0x0C Uint32 Unknown.
0x10 Uint16 Number of subobjects (N). Always 0x20.
0x14 Char[32] Name of the texture this entry must be linked to. Linked textures must start with lm_.
0x34 Uint8 Type: 0 = Spherical gradient (illuminated from 4 sides), 1 = Flat gradient (just a regular gradient texture), 2 = spherical gradient (illuminated from 1 side)
0x35 Byte[3] Padding
0x38 Uint32 A bitfield describing which entries are activated (Nth bit set = Nth entry activated). Always 0x100 (only 8th entry) in Nintendo tracks.
0x3C Sub[N] A list of entries with the following structure:
Offset Type Description
0x00 Float Intensity of the lighting of this stage (must be between 0.0 and 1.0)
0x04 Uint8 Gradient to use for this entry (see table below)
0x05 Uint8[3] Unknown.


Each LTEX entry links to a 64x4 grayscale black to white gradient texture. The table below lists the different kind of gradients.

id Type Description
0x00 x Linear gradient between x=32 and x=64
0x01 x Linear gradient between x=0 and x=64
0x02 x Linear gradient between x=16 and x=64
0x03 x2 Quadratic gradient between x=32 and x=64
0x04 x4 Quartic gradient between x=32 and x=64
0x05 x6 Sextic gradient between x=32 and x=64
0x06 x8 Octic gradient between x=32 and x=64
0x07 x Linear gradient between x=4 and x=45
0x08 -x2 Negative quadratic gradient between x=10 and x=42
0x09 -x2 Negative quadratic gradient between x=13 and x=45


The following tools can handle BLMAP files: