In some respects, it is easier to make new terrain for MiG Alley than some other games for a few reasons:
(1) The roads and railroads are painted over the top of the terrain textures by the game, so one does not have to worry about making them match up.
(2) Unlike many other games, such as EAW or CFS, MiG Alley does not make its terrain tiles match up with each other. Instead MA takes large irregular patches of a given texture and paints it over the landscape. This means that one only has to worry about each terrain texture matching up with itself, although this does mean that each texture has to be sufficiently generic not to clash too much with other textures placed adjacent to it.
(3) Owing to (2), one does not have to worry about the shape of rivers, lakes and coastlines. The game knows which parts of the landscape (or seascape) are supposed to be water and covers these areas with water textures.
In other respects, it is considerably more difficult to make terrain for MiG Alley. The problems are caused by the palette for the texture images. Unlike many other games, these are not stored in the same file as the image (as in BMP or PCX files). In order to make or edit a texture file for MA, it is necessary to convert the files back and forth between MA's native format (*.x8) and more common formats using the program tt2.exe and an MA palette file (Gpal.pal or Daypal.pal).
There are further complications with the terrain files. To begin with, in order to read these files with tt2.exe, one needs to use the switch for superclustered files (whatever they are):
tt2 -es -r img10000.x8 -r gpal.pal -w img10000.bmp
An added complication is that the terrain files seem to use their own palette, which is not available to us. If you try converting an image file using the above command, you will get a bitmap with wildly incorrect colors.
The key to making new terrain is the img10000.x8 file. This file seems to store the palette that all the other terrain files will use. In making this file, one should use the following command:
tt2 -es -r palclust.x8 -r yourfile.bmp -ep img10000.x8
The -ep switch is used to create an .x8 file that contains palette information.
Having done that, you can go ahead and create replacements for the other terrain files (img10001.x8 thru img10031.x8). It doesn't look like you need to store palette information in these files so you can create them in the usual way:
tt2 -r yourfile.bmp -r gpal.pal -w img10001.x8
I've actually been using the daypal.pal palette as it contains a few more colors. I don't know how useful it is to us, but it is possible to create your own MA palette files and remap images with them using tt2.
The following are some 'special' files:
Img10000.x8 is for the forests. As we don't have the palette for the old terrain files, it has to be replaced with a new texture. I used the forest texture from Flying Corps, as the FC bitmaps convert easily to the MA palette.
Img10013.x8, img10014.x8 and img10017.x8 are water files. My guess is that these are for sea, lakes and rivers, but I haven't really looked into it.
Img10022.x8 is the runway texture (there may be more, but I don't know about them) and img10028.x8 is the surrounding area of the base.
Img10029.x8, img10030.x8 and img10031.x8 are city textures. Img10010.x8 is for a village.
If you are planning on making your own terrain, it is highly advisable to use a custom palette. The palette information for terrain tiles comes from the palclust.x8 file. This can be changed be clustering a new palette to this file.
The first step is to make your new palette. You can go with the palette stored in the BMP you will be using, or you can edit it in a program like Paint Shop Pro. This palette is extracted for use in MiG Alley with the following command:
tt2 -r yourfile.bmp -epx newpal.pal
The next step is to cluster this new palette into the palclust.x8 file:
tt2 -es -r palclust.x8 -e newpal.pal -w newclust.x8
You can now create new terrain tiles with your custom palette in the following way:
tt2 -es -r newclust.x8 -r yourfile.bmp -ep img10000.x8
Download a small sample of modified terrain here. This contains a new img10000.x8, img10001.x8 and a batch file to copy img10001.x8 over all the other terrain files. N.B. This is NOT a finished terrain mod. It is just a sample meant to encourage terrain development in the MA community.
Download the bitmaps from the above sample here. This also includes the Flying Corps palette.
Questions or comments should be directed to jypes@yahoo.com