I was sick and bored today, and with no access to the computer, I tried messing with search and replace. I wanted to check if what I figured out is right... so here goes

Code:
94000130 FCFF0000
this is, of course, the activator. this one checks L+R

Code:
D3000000 021E3122
this is one space before the space to start from, right? in 1.0 the first space in the top left corner is 021E3124, so you start at 021E3122. And to make this code work with different game version, you just need to change the second half to fit with the version of the game?

Code:
C0000000 00000FFF
this is how many times to increment and check the offset again? in this case 4095, plus the first run through, making 4096, the entire 64 x 64 map. Right?

Code:
DC000000 00000002
Adds 2 to the offset

Code:
F2000000 00000002
copies the item for checking what you put in to search for

Code:
92000000 0000XXXX
of course this is just what it's searching for... and it can be replaced with
Code:
82000000 0000XXXX
72000000 0000ZZZZ
to replace a range, where XXXX is one less than the first hex in the range and ZZZZ is one more than the last? like for all weeds you'd do XXXX=0020 and ZZZZ=0025.

if you wanted to replace every spot in a loop, would just completely skipping this line work? it seemed to when I tried, but I don't know if that's a bad thing or not...

Code:
10000000 0000YYYY
this is just what's being placed in the spot being replaced

Code:
D2000000 00000000
the "terminator" (not the movie one though)


So if someone who knows more about this than me could tell me, am I right about this? And also tell me what exactly the 0xDC line does?

I think at least for 1.0 this seems right (I don't know why it wouldn't be right for another version except for the 0xD3 line possibly)

I made a code that worked fine to entirely remove everything in the first acre and it came out like this:
Code:
94000130 FCFF0000
D3000000 021E3122
C0000000 000000FF
DC000000 00000002
10000000 0000FFF1
D2000000 00000000
and I did a replace all weeds with blue roses that seemed to work, too. It came out like this:
Code:
94000130 FCFF0000
D3000000 021E3122
C0000000 00000FFF
DC000000 00000002
F2000000 00000002
82000000 00000020
72000000 00000025
10000000 00000019
D2000000 00000000