rpix86 progress

via http://rpix86.patrickaalto.com/rblog.html

As I mentioned at the end of my previous blog post, I am working on a new project and thus do not have much time to work on rpix86 (or zerox86). However, just before I released the previous version of rpix86, I was asked on the rpix86 forum thread whether I had any plans to make rpix86 run on a terminal window. At that time I did not have such plans, but I immediately thought that this might be something interesting that I would like to try. Thus, while mostly working on my new project, I have also made some experiments with running rpix86 using the Curses library for screen output.

My text mode screen handling has always used a "dirty buffer" approach. That is, I have a hidden buffer of the same size as the text screen (normally 80x25), and at around 60 times a second I check which characters have changed, and then only draw the fonts of those changed characters on the actual graphics screen. I thought that this approach would work fine also with the Curses library, as I would only need to draw (send via the terminal line) the changed characters. Indeed, this seemed to work fine, and I was able to get some screen output pretty easily.

After I got the basic DOS prompt screen showing, instead of working on keyboard input, I decided to add support for launching a certain exe directly. I wanted to test what happens with all those block drawing characters used by Norton Sysinfo, for example. Studying the Curses programming guides, I saw that you can use an Alternate Character Set to draw some simple block graphics characters. Thus I worked on that a little bit as well, until I got the lines looking reasonably nice on the Sysinfo screen. I also added color support, so that the end result is not far off the original. Here below is a screen copy of me running rpix86 on my Raspberry Pi using the putty terminal program from my Windows PC. Ignore the two cursor images, I don't yet handle hiding the cursor nor disabling the text mode mouse cursor properly.


Next step would be to add keyboard input, and also some warning message to be shown whenever the DOS screen goes to graphics mode, as that can not be used when in a terminal window. It will take me some time before I can release the next version, though, as most of my time goes to the new project I am working on. But, it is quite possible that the next version of rpix86 allows you to actually run it on a terminal window. :-)