Wednesday, 8 April 2009

Another Last Amazon front end

Tuesday 7th April 2009 + Wednesday 8th April 2009

Bah, TV sucks. Well that doesn't surprise me. I had nothing else too exciting to do, so I decided to work on a new front end for Last Amazon 2. This time it was a bit of a challenge, but I knew that it should be possible. I prepared a work disk .D64 and transferred all the C64 files into the cross-assembly directory for use with ACME, the same way as I did with The Last Amazon.

Kenz had shown me the mock up screen shot of what he would like me to do for the front end. Oh no ... raster splits :( Seriously, I hate doing raster bars, due to having to get those blasted things timed correctly inside $D012 splits. Ah well, it has to be done, and I shall do that.

I loaded up the Relaunch64 tool and then I created a main source file which will link all the c64 program files (including the game) and got started on the programming side of things. I started off with the IRQ interrupt player routine to see if it will run. The good news was that the player routine did play the music after assembled and crunched with PuCrunch. Now it was time for the serious part of the programming. Getting the bitmap logo and all chars displaying. To do this, I changed the background colour ($D021) so that all small text was white and all large text was yellow. So I built 10 raster splits in total. Everything displayed successfully.

Now it was time to add those raster bars into the text. Well, this I must stress was one of the worse parts of the front end programming. So I built a colour table and a raster timing table for each raster split. It took a lot of time to time out the raster splits so that the text chars looked much more tidier. As soon as I was happy with the result, I worked on the scroll text routine (Which uses raster splits as well) and then added a routine for which the player can press fire in either joystick port to play a 1 or 2 player game. Those worked okay, but sadly timing had altered again. So I moved the raster timing table and also moved the scroll text to a higher location and got everything working. Looks perfect now. Hope Alf and Kenz likes this one.

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