[TEC] Menu editing: Understanding crop

[Flopper]

All I am attempting to do here is understand what the crop numbers mean.

Here's a section from menu_1024_768.ini:

[G31 I20]
Name=Zoom in
Type=1032;Button
ItemID=0x311A0001
ParentID=0x311A0000
Pos=1,-1,40,40
Materials=4
Display=0;No stretch
Mat 0=data/menu/gui/maptools.tga
Crop 0=0,0,0,0
Mat 1=data/menu/gui/maptools.tga
Crop 1=0,0,0,0
Mat 2=data/menu/gui/maptools.tga
Crop 2=0,0.160156,0,0
Mat 3=data/menu/gui/maptools.tga
Crop 3=0,0.160156,0,0
MatFlags=0x1
TexFmt=0x9
Font=1
TextFlags=0x0
StatesColors=0xB0B0B0FF, 0xFF, 0xFFFFFFFF, 0xFFFFFFFF
;ToolTipText=2242

Here is a blowup of a test version of maptools.tga:


I see we are working with the nav map tools, which all come from the same image.

Okay, here are the 4 crops:
Crop 0=0,0,0,0
Crop 1=0,0,0,0
Crop 2=0,0.160156,0,0
Crop 3=0,0.160156,0,0

I'm guessing this is some kind of coordinate system, but I can't put it together. I see that we are working with the "zoom in", which is in the upper left. The 0,0,0,0 may mean start at the upper left corner of the whole image, perhaps. The 0.160156 may mean about 16% (1/6) of the way down the image, which makes sense.

But if that is true, where is the horizontal X component of these coordinates? Also, sometimes there is only one crop, crop 0. All this is driving me batty.

Any help is greatly appreciated.