FF7/TEX format
TEX Texture Data Format for PC by Mirex (Edits by Aali)
FF7 PC texture consists of header, an optional palette and bitmap data. Usually data are stored like palletized picture, with bitmap pixels referencing to palette. Color 0 (in palette its usually black) is usually used as transparent color.
Pixel values of 0 may or may not be transparent, depending on the color key status, more on that later. This also applies to non-paletted formats.
When bit depth is 16 then data are stored as packed RGB in style RGB555, which means 5 bits per color in one 2 byte entry. I'm not sure if it is used in FF7 at all, its probably used in FF8.
The tex format is actually very flexible and can take almost any non-paletted format as long as you describe it properly in the header.
| Offset | Size | Description |
|---|---|---|
| Header | ||
| 0x00 | 4 bytes (long) | Version, must be 1, or FF7 won't load the file |
| 0x04 | 4 bytes (long) | Unknown |
| 0x08 | 4 bytes (long) | Color key flag |
| 0x0C | 4 bytes (long) | Unknown |
| 0x10 | 4 bytes (long) | Unknown |
| 0x14 | 4 bytes (long) | Minimum bits per color (D3D driver uses these to determine which texture format to convert to on load) |
| 0x18 | 4 bytes (long) | Maximum bits per color |
| 0x1C | 4 bytes (long) | Minimum alpha bits |
| 0x20 | 4 bytes (long) | Maximum alpha bits |
| 0x24 | 4 bytes (long) | Minimum bits per pixel |
| 0x28 | 4 bytes (long) | Maximum bits per pixel |
| 0x2C | 4 bytes (long) | Unknown |
| 0x30 | 4 bytes (long) | Number of palettes |
| 0x34 | 4 bytes (long) | Number of colors per palette |
| 0x38 | 4 bytes (long) | Bit depth |
| 0x3C | 4 bytes (long) | Image Width |
| 0x40 | 4 bytes (long) | Image Height |
| 0x44 | 4 bytes (long) | Pitch or bytes per row, usually ignored and assumed to be bytes per pixel * width |
| 0x48 | 4 bytes (long) | Unknown |
| 0x4C | 4 bytes (long) | Palette flag (this indicates the presence of a palette) |
| 0x50 | 4 bytes (long) | Bits per index, always 0 for non-paletted images |
| 0x54 | 4 bytes (long) | Indexed-to-8bit flag, never used in FF7 |
| 0x58 | 4 bytes (long) | Palette size, always palettes * colors per palette |
| 0x5C | 4 bytes (long) | Number of colors per palette (again, may be 0 sometimes, the other value will be used anyway) |
| 0x60 | 4 bytes (long) | Runtime data, ignored on load |
| 0x64 | 4 bytes (long) | Bits per pixel |
| 0x68 | 4 bytes (long) | Bytes per pixel, always use this to determine how much data to read, if this is 1 you read 1 byte per pixel, regardless of bit depth |
| Pixel format (all 0 for paletted images) | ||
| 0x6C | 4 bytes (long) | Number of red bits |
| 0x70 | 4 bytes (long) | Number of green bits |
| 0x74 | 4 bytes (long) | Number of blue bits |
| 0x78 | 4 bytes (long) | Number of alpha bits |
| 0x7C | 4 bytes (long) | Red bitmask |
| 0x80 | 4 bytes (long) | Green bitmask |
| 0x84 | 4 bytes (long) | Blue bitmask |
| 0x88 | 4 bytes (long) | Alpha bitmask |
| 0x8C | 4 bytes (long) | Red shift |
| 0x90 | 4 bytes (long) | Green shift |
| 0x94 | 4 bytes (long) | Blue shift |
| 0x98 | 4 bytes (long) | Alpha shift |
| 0x9C | 4 bytes (long) | Always 8 - Number of red bits (Not sure what the point of these fields is, they're always ignored anyway) |
| 0xA0 | 4 bytes (long) | 8 - Number of green bits |
| 0xA4 | 4 bytes (long) | 8 - Number of blue bits |
| 0xA8 | 4 bytes (long) | 8 - Number of alpha bits |
| 0xAC | 4 bytes (long) | Red max |
| 0xB0 | 4 bytes (long) | Green max |
| 0xB4 | 4 bytes (long) | Blue max |
| 0xB8 | 4 bytes (long) | Alpha max |
| End of pixel format | ||
| 0xBC | 4 bytes (long) | Color key array flag (this indicates the presence of a color key array) |
| 0xC0 | 4 bytes (long) | Runtime data |
| 0xC4 | 4 bytes (long) | Reference alpha (more on this later) |
| 0xC8 | 4 bytes (long) | Unknown |
| 0xCC | 4 bytes (long) | Unknown |
| 0xD0 | 4 bytes (long) | Palette index (runtime data) |
| 0xD4 | 4 bytes (long) | Runtime data |
| 0xD8 | 4 bytes (long) | Runtime data |
| 0xDC | 4 bytes (long) | Unknown |
| 0xE0 | 4 bytes (long) | Unknown |
| 0xE4 | 4 bytes (long) | Unknown |
| 0xE8 | 4 bytes (long) | Unknown |
| Palette data (ignore this section if palette flag is 0) | ||
| 0xEC | Palette size * 4 | The raw palette data, always in 32-bit BGRA format |
| Pixel data | ||
| Varies | Read width * height * "bytes per pixel" bytes of data. If there's a palette, every pixel is an index into that palette, otherwise use the pixel format specification. | |
| Color key array | ||
| Varies |
Number of palettes * 1 bytes. |
|
Color keying: If the color key flag is zero, no color keying is performed and the color key array is ignored. Otherwise, the current palette index is used to retrieve a single byte from the color key array, this is the new color key flag, zero means don't do color keying. If there is no color key array (and the color key flag is not zero), you should always color key.
Reference alpha: Only applies to paletted images, if the alpha value sampled from the palette is 0xFE, this value should be replaced with the reference alpha.
