RCT/RCT2 Screenshots for Dummies

(Please note that this is a RECOMMENDATION! Using Paint (or similar) to save as PNG is just as fine.)

So you want to post a screenshot of that really neat roller coaster you made in RCT? Follow these steps to make your life easier (at least marginally).

1. Take the screenshot you want in game. Don't use your "print screen" key or some other application (this will become apparent why later).

2. Download a program called OptiPNG (http://optipng.sourceforge.net/). You'll probably want the one "The Windows (32-bit) build" one (stable, not developmental). Extract optipng.exe somewhere you'll remember where it is (your desktop, for example).

3. Open Notepad (or your plain text editor of choice), and paste the following three lines into it:
@echo off
optipng -o7 -zm1-9 -strip all -i 0 "%~1"
pause

3.5. If you're using Notepad, go to File > Save As. Go the the same folder where you extracted optipng.exe and select "Save as type: All Files (*.*)", then enter something like "optipng.bat" (it can be whatever AS LONG AS the file extension is ".bat").

4. Find the screenshot you saved previously. Now comes the fun part (and where putting OptiPNG on your desktop helps): drag the image you want to post ONTO the .bat file you just saved from Notepad. OptiPNG will now optimize your screenshot and save it back to the directory where your screenshot was under the same name. For example, if I dragged "SCR66.bmp" onto the batch file, OptiPNG will have saved it as "SCR66.png". Please note that this may take a minute or two, depending on how fast your processor is and how large the screenshot dimensions are.

5. Upload your newly taken screenshot and enjoy!

Repeat steps 1, 4 and 5 every time you want to post a screenshot.
Have Fun!



FAQ
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Q: What does that batch code do?
A: It basically tells OptiPNG to take the input image (in this case, because we're drag-and-dropping it, "%~1") and optimize it using the "-o7 -zm1-9 -strip all -i 0" options (which will produce the smallest possible size image).

Q: Why do I have to take the screenshot in game? Wouldn't a "print screen" screenshot work?
A: Yes, but there's a problem. RollerCoaster Tycoon (and some other games, including other games made by Chris Sawyer) uses a 256 color palette for it's graphics. The reason we exclusively use PNG or GIF images is because JPEG images were designed to assume the image has a 16.7 million color space. PNG and/or GIF, on the other hand, can have limited color spaces (or, in the case of GIF, a maximum of 256 colors). This proves to be useful for our purposes because OptiPNG will automatically reduce the color space without ruining the image itself. This in turn produces a smaller image size because less data is being stored in the file itself. The reason you DON'T want to use a "print screen" screenshot is that your image would end up having more than 256 colors, thereby completely destroying any file size savings you would get by using PNG/GIF format.

tl;dr there are too many colors and that ruins the file size savings you get from using PNG

Q: Where do I find my screenshots?
A: Wherever you installed the game. If you go to the game's directory and you don't see any images, check %LocalAppData%\VirtualStore (click Compatibility files). Windows Vista and later has a really stupid file system virtualization feature built into UAC that causes anything being saved by a program being run by a user without proper privileges to be saved in the user's profile.

Q: How do I add custom music?
A: Out of scope, see http://pastebin.com/QwHJ4zDL