1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
GRFCodec - A tutorial
by [1]Josef Drexler.
This tutorial is a list of the steps you need to take to edit a GRF
file, and if you like, send your modifications to others.
Since all GRFCodec programs are command line utilities (no graphical
interface available), you have to make yourself familiar with the DOS
or Windows command prompt. However, that's beyond the scope of this
tutorial.
These are the basic steps to modifiy a GRF file:
1. Decode the GRF file
2. Edit the PCX file
3. Encode the GRF file
Optional steps to distribute your changes:
4. Make a GRD or self-extracting file
1. Decode the GRF file
After installing the GRFCodec programs into your TTD folder, simply
run GRFCodec. At the command prompt, type
grfcodec -d trg1.grf
This will decode trg1.grf, and put an editable PCX file in the SPRITES
folder.
Note that the image will be quite huge, and if you instead want to
split it into smaller files, use
grfcodec -d trg1.grf -w 800 -h 600
1a. Choosing a palette
Skip this step unless you find that the colours are wrong. In that
case, you need an extra option on the GRFCodec command line: the -p
option. It tells GRFCodec to choose a different palette.
After the -p option, you specify a number indicating which palette you
want. You have the following choice:
Number Meaning
1 DOS TTD
2 Windows TTD
3 DOS TTD, Candyland
4 Windows TTD, Candyland
5 TT Original
6 TT Original, Mars landscape
So, for example, use "-p 2" when you're decoding a file from the
Windows version of TTD, like so:
grfcodec -d trg1r.grf -p 2
2. Edit the PCX file
For this, you open your favourite graphics editor, like Paintshop Pro,
Adobe Photoshop, or any other graphics editor that can deal with PCX
files. (Just about all of them can.)
You should then load trg1.pcx in the SPRITES folder. Or, if you used
the second command above to split it into smaller files, open
trg10000.pcx, which is the first part. The following parts simply have
higher numbers.
If at this point you find that the colours are wrong, you need to
decode the GRF again, using a different colour palette. In that case
please follow the instructions in step 1a).
If however everything looks fine, you can then start changing the
sprites. Note that it is fairly difficult to actually change their
size, but changing the look is easy enough.
Once you've changed all you need, save the PCX file again.
3. Encode the GRF file
This step is the reverse of step 1), it takes the PCX file(s) and
makes a GRF file out of them. At the command prompt enter
grfcodec -e trg1.grf
This will take a bit longer than decoding, but shouldn't take too
long. Once it's done, you can start TTD and see the fruits of your
labour!
4. Make a GRD or self-extracting file
So now that you have successfully changed a GRF file, you'll of course
want to give your awesome modifications to other people. You can
simply send them the new trg1.grf file, but that has a few
disadvantages. First, the GRF files are fairly large, so downloading
them is going to take a fairly long time. Also, this means that your
friend will lose all changes he made to his own trg1.grf file.
If only there was a way to send only the changed sprites...
...and luckily, there is! It's called GRFDiff, and you use it like
this:
grfdiff trg1.bak trg1.grf
Here, trg1.bak is a backup copy of the original GRF file. GRFCodec
should have made it during step 3. Once it exists, GRFCodec won't
touch it again, so it'll always remain the original copy.
Now what this command does, is take all the sprites that are new and
put them in a file called trg1.grd. This file should be fairly small,
so that you can easily send it to your friend. What your friend then
has to do is run GRFMerge like this:
grfmerge trg1.grd
That will integrate your changes into his trg1.grf, and everyone will
be happy.
Unless he doesn't have GRFMerge...
...in that case, you can instead tell GRFDiff to make a
self-extracting file. That means it turns the GRD file into a program,
which you can run instead of GRFMerge. To do that, run
grfdiff -x trg1.bak trg1.grf -o yourmod.exe
That will make yourmod.exe, or any other name you give it. Be
creative, and make the name relevant to what you actually changed.
Then simply send out yourmod.exe, and tell people to copy it to their
TTD folders and run it. Tadaa! They've got your modified sprites.
If you want to make your .exe file compatible with both the DOS and
the Windows version of the game, you of course need to edit both
trg1.grf and trg1r.grf. Then you combine the changes from both files
into one executable like this:
grfdiff -x -o yourmod.exe trg1.bak trg1.grf + trg1r.bak trg1r.grf
When run, yourmod.exe will patch either both of the files if they are
installed, or otherwise it will just skip those that it can't find.
That way, it'll work no matter whether the DOS or the Windows version
is installed, or even if both are present.
Easy, wasn't it?
______________________________________________________________________
Copyright © 1999-2003 by Josef Drexler.
Last changed on May 17 2003 15:45 EDT by [2]Josef Drexler
References
1. http://www.ttdpatch.net/email.php?GRFCodec%2CTutorial
2. http://www.ttdpatch.net/email.php?TTDPatch%2CGRFCodec
|
