7800basic Newbie problem

[pacgreg]

I was trying to learn this 7800basic stuff after pretty much dropping bB at first sight of it, but now I put it down for a long time because I just can't get the second sprite to line up properly, or even display the right sprite. If someone could help me fix one of these problems I'll probably feel motivated again to build the rest of the game.

Thanks!

Greg

Metal Gear.zip

[RevEng]

Here's the fixed .bas file.

 

temp1 doesn't work as a position for plotsprite, as it gets overwritten by the function before that parameter is used.

 

metalgear.bas

[+Random Terrain]

There are a ton of variables with 7800basic, so it's weird that people want to start out using temp variables. It's kind of like splashing around in a tiny mud puddle next to the ocean. Dive in and enjoy the ocean of variables.

[RevEng]

To be fair to Greg, I used temp variables in a couple of the samples where it was safe, mainly because I was lazy to dim another variable. But yes, on the 7800 you want to think about memory usage in terms of clumps RAM, rather than worrying about individual bytes.

 

I'll modify those samples to use dim'ed variables instead. Your site and the guide mentions the usage of temp variables and the pitfalls, but its better to start people off with safer habits.

[pacgreg]

RevEng was right about the samples throwing me off with temp, but now I understand that much. The next problem I encountered is trying to make a background function. I need some help seeing how plotting the map works and after that I can make games as everything after that is almost identical to bB coding. Can someone take a look and help me get this working?

Thanks again

Metalgear.zip

[RevEng]

Here's a version with working plotmap. I had to add some parameters to the command - I've commented what was added.

 

If you're going to be designing a bunch of screens, you might look at the tiled map creation functionality. Basically you can use the tiled graphic editor to design screens, and import them into 7800basic and use them instead of "alphadata" for the screens. Atarius Maximus posted a tutorial on it, which you can find here.

metalgear.bas