Uploaded June 2026 | Updated September 2026, 2 weeks ago
My previous port of the TI99/4a game Beyond Parsec was pretty much complete expect for a game breaking bug - the asteroids would speed up on occasion when shot or sometimes will skip half the screen.
I think this was a result of nested gosub commands. I had seen similar issues with my Room Raiders game. I essentially flickered everything to give me more sprites but I noticed if I added something to one frame but not the other some funky stuff will happen. For instance, in Room Raiders, I added a gosub on one frame but not the other and it would make things spawn weirdly but if I put that same gosub (despite it not being called on the other frame) in that section of code things would behave as intended. I personally think this was an issue when compiling as I could not identify the issue and noticed it in a couple programs.
With the introduction of PXE and my "gravity" code for the shopping carts in Bag Boy, I decided to test it with Beyond Parsec. For one, with PXE I do not have to flicker the asteroids. While in the DPC+ version I used the stack to essentially load and save the coordinates of the asteroids, with PXE I do not have to do that. This gets rid of having separate banks for the flickered asteroids.
I also can display more asteroids as in the DPC+ version I reduced the amount of asteroids by two so that I can try and create a planet with the playfields. I also simplified the code for the momentum. The original code I used for Beyond Parsec was based on my code for Forest Moon Attack. When making Bag Boy I simplified the code so that shooting an asteroid in this new version only uses a fraction of what I used prior.
I do need to work on the collision detection of the asteroids in this POC but if this works out as I think it would I can quickly get back to where I was. Plus with the playfield offsets I can make more dynamic playfields, more sprites I can use to implement the powerups better, and maybe use implement some of the other ideas I originally had but scaled back to build upon the port.
My previous port of the TI99/4a game Beyond Parsec was pretty much complete expect for a game breaking bug - the asteroids would speed up on occasion when shot or sometimes will skip half the screen.
I think this was a result of nested gosub commands. I had seen similar issues with my Room Raiders game. I essentially flickered everything to give me more sprites but I noticed if I added something to one frame but not the other some funky stuff will happen. For instance, in Room Raiders, I added a gosub on one frame but not the other and it would make things spawn weirdly but if I put that same gosub (despite it not being called on the other frame) in that section of code things would behave as intended. I personally think this was an issue when compiling as I could not identify the issue and noticed it in a couple programs.
With the introduction of PXE and my "gravity" code for the shopping carts in Bag Boy, I decided to test it with Beyond Parsec. For one, with PXE I do not have to flicker the asteroids. While in the DPC+ version I used the stack to essentially load and save the coordinates of the asteroids, with PXE I do not have to do that. This gets rid of having separate banks for the flickered asteroids.
I also can display more asteroids as in the DPC+ version I reduced the amount of asteroids by two so that I can try and create a planet with the playfields. I also simplified the code for the momentum. The original code I used for Beyond Parsec was based on my code for Forest Moon Attack. When making Bag Boy I simplified the code so that shooting an asteroid in this new version only uses a fraction of what I used prior.
I do need to work on the collision detection of the asteroids in this POC but if this works out as I think it would I can quickly get back to where I was. Plus with the playfield offsets I can make more dynamic playfields, more sprites I can use to implement the powerups better, and maybe use implement some of the other ideas I originally had but scaled back to build upon the port.
