Car graphics

Cars in VDrift are composed of multiple components. Their graphical representation consists of geometry(mesh), textures and a draw flag which denotes whether the object is to be handled as opaque, transparent or emissive. The setup is done in car parameters files <CARNAME>.car.

Geometry(meshes) can share textures. The number of meshes and textures should be kept low for performance reasons.

Example of a graphical component setup:

[some_car_part]
texture = diffuse.png, misc1.png, misc2.png  # (required) the first texture(diffuse.png) is required, additional textures(misc1.png, misc2.png)are optional
mesh = model.joe                             # (required) geometry (mesh)
position = 0.736, 1.14, -0.47                # (optional) relative mesh position
rotation = 0, 0, 30                          # (optional) relative mesh orientation 
scale = -1, 1, 1                             # (optional) mesh scale factor
color = 0.8, 0.1, 0.1                        # (optional) base diffuse color; blended with diffuse texture using alpha channel as mask
draw = transparent                           # (optional) draw flag: opaque, transparent, emissive; opaque is default

Geometry

Car geometry is stored in VDrift native JOE format. Import/export scripts for Blender are available here: https://github.com/VDrift/blender-scripts

Shared Geometry

When loading a mesh VDrift first checks cars/<CARNAME> directory and then falls back to the carparts (and trackparts) directory. The assets in this directory are shared, can be used by all cars.

Generated Geometry

Car [wheel.<id>.brake] and [wheel.<id>.tire] (id = [fl, fr, rl, rr]) components will be auto-generated by the game when no mesh is provided. Their dimensions are derived from the provided brake and tire data.

The mesh of the [wheel.<id>] component contains only the wheel disc at unit size (0.5 m radius). The rim is auto-generated by the game from tire dimensions. The disk mesh is scaled to fit it.

To be able to use a custom wheel mesh (which already has a rim) the wheel component the optional property genrim has to be set to false.

[wheel.fl]
texture = my_wheel_texture.png
mesh = my_wheel_with_rim.joe
genrim = false

Textures

VDrift supports multi-texturing for more realistic geometry surface graphics. Texture are RGBA images in PNG format. As of April 2013 DDS(DXT1-3) is also supported.

• 1. Texture (required): Diffuse color (diffuse albedo or diffuse reflectance) in the RGB channels and Color Blending mask in the A channel.
• 2. Texture (optional): Specular reflection (fresnel reflection coeff at 0 deg) in the RGB channels and Glossiness (surface roughness) in the A channel.
• 3. Texture (optional): Normal map (tangent space normals) in the RGB channels.

Shared Textures

Analogous to geometry loading, when loading a texture VDrift first checks cars/<CARNAME> directory and then falls back to the carparts (and trackparts) directory.

Car Skins

The diffuse texture of the car [body] component can be swapped by the player against textures placed in <CARNAME>/skins directory.