Materials and the Material Editor
Click the Edit Material button in the Control Panel to enter the Material Editor.
The top part of the Material Editor controls the Material you're currently editing. The < and > buttons can be used to cycle through the list of Materials. The top right control will show the name of the Material you're currently editing. When you start TKD3, only the 'Default' Material (index: 0) is available. The 'Default' Material cannot be edited, apart from global terrain 'bumpiness' settings.
To create a new Material, click the New button. A Material called '< No 3D view >' will be appended to the list of Materials. Click the L (Load) control (or enter directly its name) to load an A3e material from the "materiali/" directory (please refer to the A3e documentation for more information about A3e materials).
Note: do not use spaces in Material names!
Once a new Material has been created and its visual information has been loaded, you should edit it, in order to add the required dynamics information and/or modify its visual appearance. The Material Editor window is logically subdivided into two parts to accomplish this task: controls used to modify the Material dynamics characteristics are placed in the left half, the other controls may be used to change the Material visual appearance.
Material Dynamics Info
There are many controls to modify the Material dynamics characteristics:
- Hard/Soft toggle button: controls whether this material is an 'hard' one, such as tarmac or concrete, or is made of somewhat loose particles, such as gravel or grass.
- Outrun toggle button: controls whether cars should usually run on or avoid track parts made of this Material; this setting is very important because it controls the way AI cars discover their best line (they wont't run on track parts marked as Outrun). From within the Material Editor you assign the Outrun property to a whole Material, but in the Segments/Stripes Editor you may override this setting on a per-Segment, per-Stripe basis.
- Grip: the normalized grip (friction coefficient multiplier) of the Material, both for Dry and Wet conditions. Please note that these are normalized values, not actual friction coefficients. VGP3 uses quite a complex model for collisions and friction forces, the actual grip, especially for tyres, is computed using many parameters that come from the tyre itself. This normalized grip value is only a constant used to multiply the final results; as an example, if for, say, a tarmac Material, you insert a value of 0.9 in the Dry Grip control and 1.1 in the Wet one, the actual friction coefficient of this Material will be calculated in real-time by VGP3, but being the same tyre type, compound, speed, temperature and so on this tarmac will give 10% less grip than a "standard" tarmac does in dry conditions and about a 10% more grip (again, than a "standard" one) when it's raining.
- Kinet: currently unused (tyre data override this setting)
- DeepG: the real (not normalized) "deep" grip of the Material. This value is meaningful only for soft Materials and represents the final maximum friction coefficient that comes from the Material shear strenght. When grooved tyres excavate a soft ground and "sink" into it, their maximum friction coefficient is limited only by the internal Material friction, cohesive factor and shear strenght; such maximum friction coefficient can be entered from this control. Pay attention to the fact that the extent to which a tyre can reach this final friction coefficient depends upon many tyre data, especially on the tyre groove factor - slick tyres, for instance, won't usually add any additional "deep" grip (Note: this control is currently unused, as of this writing any soft Material gets a standard "deep" grip of 1.0)
- Level: tyre "sinking" level. This value controls how much tyres tend to sink into a soft ground. It roughly represents the sinking depth (in meters), but of course it's again a normalized value because the real depth depends upon many static and dynamic tyre data, including weight and contact patch area. This setting mainly affects the rolling resistance of tyres: the more a tyre "sinks" into the ground, the more difficult it is to move/roll it
- Friab: the Material friability, ie how much Material particles tend to be "loose" and move. This value mainly affects the additional slip angle of tyres you may experience when driving on loose terrains, such as gravel or sand. The higher the value, the more the particles are allowed to move in respect of each other; tyres will then tend to slip and move sideways even if they are virtually in full adhesion with ground because they are the very ground particles themselves that are "moving" under the wheels
- Cohes: the viscous Material combined effects of cohesion and density, ie how much difficult it is to "push" a soft Material around. This value works in combination with the Level setting and affects the rolling resistance and the "hydroplaning"-like behaviour; as an example, a tyre running at high speed on an high density sand Material will tend to "float" and "hydroplane" on it
- B HF/P HF: the Material bumpiness. The B control represents the amount (in meters) of surface bumpiness, the P control is the period of the Perlin noise function used to generate bumps (higher values give more slowly varying surfaces). These controls are called HF (high frequencies) because they should be used to generate the high-frequency bumps usually found in noisy surfaces such as gravel, sand or grass
- B LF/P LF: the global, low frequency bumpiness, applied to everything. Those controls work as the HF ones, with the difference that noise generated is applied at once to every Material (ie, to the whole track)
- Max H2O Factor: how much this Material is allowed to "get wet". Default is 1.0, but you may insert lower values to simulate Materials that tend to remain dry even in wet conditions
Material Visual Info
From the Material Editor window you can modify some visual characteristics of Materials. Pay attention to the fact, however, that you have limited control over the 3d appearance of Materials from within TKD3, and that if you want to deeply change such characteristics you'd better modify directly the .a3em files in the "materiali/" directory:
- Tex controls: show the name of the textures used by this Material. You can replace textures by loading different ones using the L control to the right (as of this writing, only uncompressed 24bit or 32bit .bmp files). Pay attention to the fact that if you change a Material texture you cannot use any more the old Material name and TKD3 will automatically suggest you a new one (otherwise the old Material would be overwritten)
- Tile toggle button: forces a non-tiled textured Material to be tiled in the XZ plane (ignored for tiled textures)
- UVmp: control the scaling ratio of tiled textures, the lower the number, the bigger the texture. Don't use this control for Materials used as Terrain, the Terrain Editor gives you better control over texture scaling/rotation