[ClockWatcher]

I've compiled map_C's for my slot map using 8bit Grayscale, and it works fine.

Yes, all examples I have seen of map_C.tga are 8 bit grayscale.

See for instance Balaton, map_C.tga is 1024x5824 pixels, image size is 5824 K Bytes, i.e. i byte (8 bits) per pixel.

I think there is difference in the coastline (shallow or steep) according to the shading between black (sea) and white (ground) but I am not sure of that.

Maraz

Maraz, you are right.

The way I do my map_c is to use my SRTM map, map_c, at 1 pixel per 200m, set all water features to RGB = 0 (black) and land to RGB = 255 (white). I convert this to a .tga file, greyscale 8 bit. Map_c needs to be 1 pixel = 50m scale, i.e. 4 x as large as the texture (map_T) and height maps (map_h). When I scale it up it automatically gets some dither applied by Gimp, giving a softer edge to the water features, as the shade of grey becomes lighter, the water appears “shallower”. The darker the the shade of grey, the “deeper” the water appears. To give a better edge I usually apply a gentle application of the “Blur” tool to the image.

I then convert this map_c to the sliced version and the table file required by IL2.

For rivers I use a brush tool with a 1 pixel black area and a 1 pixel grey surround, get some nice effects with this. To make the river/stream larger I just change the size of the brush or go over the line again. The only pity is that all rivers are a minimum of 50 m wide! You can even draw rivers on a gentle slope, but on steep ones the terrain “bleeds” through the river as it is semi-transparent.