Vehicle Graphics File Format

Overview

Contains all the images for vehicles. There are a lot of images in each file to allow the vehicles to roll and pitch as they move up and down hills. In my opinion the effect is not really noticed and good easily be dropped by the game.

Vehicle graphic files are only found by extracting the images from the tanks.zfx file. See the zfx tool and the ZFX file format for more details on these files.

File Contents

There are always 17 images in each vehicle file. Each of the images shows the vehicle/turret at a different pitch and roll.

image description
    0 flat and level
    1 unknown
    2 unknown
    3 unknown
    4 unknown
    5 unknown
    6 unknown
    7 unknown
    8 unknown
    9 unknown
   10 unknown
   11 unknown
   12 unknown
   13 unknown
   14 unknown
   15 unknown
   16 unknown
   17 unknown

My guesses as to what the images relate to are:

One image for level ground (probally image 0)
Two images for each tilt/roll, one for a minor tilt, another for a major tilt
Eight possible directions for tilt/roll (N,S,W,E,NW,NE,SW,SE)

Now can somebody look at all the images and figure out which ones are for what graphic.

If you want to add a new vehicle graphic for now all I would do is just copy the flat and level graphic to the other 16 slots. You really can't notice the tilt and roll that much.

File Extensions

Extensions are in the form: .(n|z)(n|s)(t|h)

First letter indicates normal (n) or zoom (z) image
Second letter indicates UNKNOWN
(in the rT34e vehicle the n was dark green and s was light green, maybe summer/winter?)
Third letter indicates turret (t) or hull (t) image

File Types

The first byte in the file is the file type.

Indicates what type of images the file holds.
Is very closely related to file extension (see above section)

This table indicates what the file type should be for the extension of the file (or vice versa, what the extension should be for a given file type).

.ext type description
.nnh    0 normal N hull
.nnt    1 normal N turret
.nsh    2 normal S hull
.nst    3 normal S turret
.znh    4 zoomed N hull
.znt    5 zoomed N turret
.zsh    6 zoomed S hull
.zst    7 zoomed S turret

Header Format (484 bytes)

 offset    size type       name          description
      0       4 int        filetype      each extension has a unique type, see above
      4       4 int        imageDataSize length in bytes of all image data (filesize-484)
      8     272 int[17][4] pointTable    each image has 2 pointss (x,y) for lining up turret and shadow
    280     136 int[17][2] sizeTable     w,h in pixels for each image
    396      68 int[17]    offsetTable   offset from start of image data (image data always starts at offset 484)
} NntHeader;

Image data is stored as 16 bit pixels (0rrrrggggbbbb). See Pixel Format below for some simple C code that you can use to pack/unpack these pixels.

The hotpoint is used to align the turret, hull and shadow. Here is what happens when you don't do this correctly.

Example of misplaced hotpoint.

Pixel Format

// PIXEL FORMAT
//
// Artwork is stored as 16 bit graphics.  Each component of the pixel is
// made up of red, green and blue.  Components have a value between 0 and 31
//
//
typedef unsigned short  CC3PIXEL;

// builds a CC3PIXEL from r,g,b where r,g,b are in the range 0..255
#define CC3PIXEL_RGB255(r255,g255,b255)     (CC3PIXEL)(((r255 >> 3) << 10) | ((g255 >> 3) << 5) | ((b255 >> 3)))

// breaks the CC3PIXEL into red,green,blue componentes (values will be 0..31)
#define CC3PIXEL_R(cc3pixel)    ((cc3pixel>>10)&0x1f)
#define CC3PIXEL_G(cc3pixel)    ((cc3pixel>>5 )&0x1f)
#define CC3PIXEL_B(cc3pixel)    ((cc3pixel    )&0x1f)

// same as CC3PIXEL_xxx but scales the values correctly into the range of 0..255
#define CC3PIXEL_R255(cc3pixel) ((CC3PIXEL_R(cc3pixel) << 3) | (CC3PIXEL_R(cc3pixel) >> 2))
#define CC3PIXEL_G255(cc3pixel) ((CC3PIXEL_G(cc3pixel) << 3) | (CC3PIXEL_G(cc3pixel) >> 2))
#define CC3PIXEL_B255(cc3pixel) ((CC3PIXEL_B(cc3pixel) << 3) | (CC3PIXEL_B(cc3pixel) >> 2))