Many new users of CA are familiar with the fact that Chess Tiger is the built-in chess engine used for many analysis tasks. But CA also has the ability to communicate with many other chess engines as well. In fact, CA is one of the few windows chess applications that has maintained support for many of the old "classic" engines that still run under DOS.
Rebel is one of the engines that CA supports through its "external" analysis facility. And since Ed Schroeder has recently released a free beta version of Rebel 12, I thought it would be appropriate to go over the procedure for getting CA to work with Rebel.
Getting Rebel and CA configured
The first step in the process is to go download the free beta version of Rebel 12. After you've unzipped the install archive, execute the file called "install". You will be prompted for a directory on your hard drive, with the default being c:\rebel12. Install Rebel wherever you want, but remember the location you used.
Then you want to start CA, and select the "Engines setup" entry under "Tools". Then click on the "Add" button near the bottom of the engines setup dialog box. You'll then be presented with a window that looks something like the screen shot to the right. What you will want to do is fill in the entries in the box with (1) the name of the engine (Rebel 12), (2) the engine type (Rebel 10), and (3) the appropriate location and executable name for rebel 12 (c:\REBEL12\REBEL.exe in this instance).Ok, now you're all set to go.
External engines are supported only through some of the older analysis functions in CA. So that means that you cannot use Rebel for things like interactive analysis or analysis by time or level. However, there is nothing stopping you from getting analysis on a specific position.
To invoke the rebel engine, go up to the engine button bar, and click on the button shown in the screenshot to the right. Then select "Standard" from the pull-down menu. You will then be presented with a dialog box with a pull-down menu for the various installed chess engines near the bottom of the dialog. Select Rebel 12 from the list.
Rebel will then start up in a DOS window. When it starts, go to the "Levels" menu, and select "Analysis". The Rebel engine should then start analyzing the position that was on the board in CA. When you feel it is proper, enter the first few moves of the variation that rebel presents to you. Then click on the small "x" in the upper left hand corner of the screen. Rebel will close, and you will be taken back to CA. There will be a dialog box on screen where you can determine whether to insert the analysis into the current game.
Another way to set things up
This can be done by repeating the setup procedure that I outlined earlier, with a slight change. Instead of choosing Rebel 10 as the engine type, you want to select "Generic EPD" instead. If you want, give it a name of Rebel 12 EPD, and use EPD as the subdirectory to store the positions in. Using the generic EPD setup option also allows you analyze collections of positions that you mark in CA. These will be written to an EPD file, which will be written in Rebel's EPD directory.
Ok, here's the analysis procedure in a nutshell. First, mark a few positions in a game for analysis purposes (use the F12 key). Then click on the button called "Analyze marked positions" in the engine toolbar (it has a big question mark on it, but is to the right of the button used for analysis of single positions). Then, in the resulting dialog box, select the Rebel 12 EPD engine.
Once Rebel 12 starts, you will need to select "Analyze EPD file" from the "Extras" menu. Then, navigate to the EPD subdirectory in the Rebel 12 folder. Then select the file called CA000.EPD. You will then be asked for an analysis time - put in the time you want the engine to take on each position.
The analysis will start. When it is completed, you will have to close Rebel using the "x" in the upper left hand corner of the screen. You will then be taken back to CA, and you can select which variations to insert. While I will agree that this procedure is not totally automatic, CA is the only program that even has this kind of support for older engines.
The new Rebel 12 engine can be used within CA, using its support for legacy chess engines. I outlined two methods for using the Rebel engine under CA. The latter procedure, in which Rebel is configured as an EPD processor, is also useful for many other chess engines as well.