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 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! ______________________________________________________________________ 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