Sid Meier's Gettysburg & Antietam - Ground Texture
I did a test with Gtex3 on SMG, putting a number on each square, different colours for each row, to see where they are used.
In the 1st row:
The 1st square is used for grass when "j" is pressed to remove terrain and when the preference for "show grid" is selected.
The 2nd & 3rd squares are used for grass.
The 4th square is wheat field, the 5th corn field.
In the 2nd row:
The 1st square is for forest (including orchard).
The 2nd is for outside corners of forest or fields.
The 3rd is for edges of forest or fields.
The 4th is for inside corners of forest or fields.
The 5th & 6th squares do not appear to be used.
In the 3rd row:
The 1st square is for town.
The 2nd is for outside corners of town.
The 3rd is for edges of town.
The 4th is for inside corners of town.
The colour of these is changed on the sunny and shadow sides of hills. This appears to be one of the occasions they have used the system of starting with a colour near the middle of a shade in the palette and moved out left and right of this to brighten or darken. If you change a colour to one that is to close to the end of a range, it might be moved into a different shade range in the palette giving unexpected results. By changing all the dots on the grass squares to palette index 104 - light pink, I had pink dots on one side of the hills then a row with indigo (palette 102) then yellow on the other side of the hills (palette 101 and less).
The 5th square supplies the palette index to be used as the centre of the range to be used when the "line of sight" icon is clicked. This is usually index-9 Mid Grey RGB=135/135/135. This gives mid grey along the crests, with lighter greys on one side and darker greys on the other side of hills. e.g.:
Changing the line of sight colour to background colour (index 0) gave this:
Editing the palette to give a unique colour to index 246 (in the middle of the Windows colours) gives:
An example of the results of an edited Gtex3.pcx file, from the SMG Fredericksburg battle pack:
SMA has more rows for more uses in its Gtex3 including for impassable water.
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