The interform procedural texture generates a texture from two color index maps and a palette. The effect varies, but is usually used for bubbling or flowing effects. It is highly recommended that you play with the interform procedure explorer in Kai's Power Tools before trying to make interform textures of your own.
ATD1 type = interform width = integer height = integer palette = filename mother = filename mother_move = string (optional) mother_vx = float (optional, for scrolling) mother_vy = float (optional, for scrolling) mother_speed = float (optional, for wander) mother_rate = float (optional, for wander) mother_strength = float (optional, for wander) father = filename father_move = string (optional) ... (other options same as for mother image)
|none||No movement whatsoever. This is the default value.|
|scroll||Scroll the texture continuously with speeds specified by mother_vx and mother_vy. These values are in texture units per second. For example, if you have −1.0 for mother_vx and 0.5 for mother_vy then after one second, the mother will have scrolled its entire width to the left and half its height upwards.|
|wander||Scroll the texture in a random direction but change the direction of travel over time. The scrolling speed is controlled by mother_speed, the amount of change in direction is controlled by mother_rate, and the strength of the steering force is controlled by mother_strength. Note that these are all optional values and do not need to be specified.|
The interform procedural texture takes two color maps, the mother and father, averages the values of corresponding pixels and uses that value as a lookup into a palette. By constantly moving the color maps around, very interesting effects can be created. Keep in mind that when you are creating the color maps, you are not creating two greyscale images that are going to be blended together in any normal way.
It is recommended for the best interform effects that the mother and father textures are "smooth" textures where the index value does not vary too quickly between successive pixels. Interform textures sometimes have a tendency to look blocky and pixellated, otherwise.
No examples are presented here because it is rather difficult to capture the interform effect without many frames in an animated GIF and I have a lot of tasks on my list to do. Please take a look around map joeyproc for a variety of example interform textures.