Re: [stella] Big Dig (My Other 2600 game)

Subject: Re: [stella] Big Dig (My Other 2600 game)
From: Christopher Tumber <christophertumber@xxxxxxxxxx>
Date: Mon, 21 Oct 2002 09:18:09 -0400
>I really like what I see so far in "Big Dig."  I have often thought Mr. 
>Driller was a game ripe for a 2600 conversion - simple concept, no horizontal 

I really, really love that game! It has the balance between arcade and puzzler just right. And I always like games that are an effective synthesis of previous games (Tetris and Boulder Dash)

>I am curious as to how you're storing the information on what blocks are in 
>each row.  Did you compress each row down to a couple of bytes or are you 
>using one byte per block?

1 byte per block. The calcs required to "associate neighbouring blocks", "remove blocks", "check if blocks need to fall" and "make blocks fall" are CPU intensive (and tricky) enough without having to bitmask out the data. It's a series of "travelling salesman" problems with no recursion and it munches CPU cycles like crazy...

>I did notice a couple of strange behaviors, which you may or may not already 
>be aware of.  If some blocks are hanging from the top row, connected due to 
>being the same color, and that top row scrolls off the screen, the hanging 
>blocks fall instead of still being considered connected.  In other words, you 
>may need to keep a memory of what has passed by.

Yeah, I used to have a virtual playfield that extended up a couple rows, but I needed the RAM. However, I'm much more accustomed to consolidating bitflags and sharing variables thanks to Space Instigators so that might come back.

>While you are falling, if you hold the joystick left or right and there is a 
>block next to you, you can halt your fall.  :)

Hrm, you're prolly not supposed to be able to move while falling. Not sure if that's a bug or a feature, it's been a while since I've been in the code...

>I don't know if it's because you have no obstacles at this point, but I found 
>that I could stay in the same column and dig straight down with no danger of 
>getting clobbered.  I drilled down the column just to the right of where you 
>start for several minutes with no problems.  Perhaps as you add more elements 
>it will be a little more dangerous.

Yeh, it's the same with Mr. Driller. There's usually no big problem drilling straight down - except for the "brown" (roadblock) blocks and having to detour to pick-up air...

>All in all, it looks to be a fun one!  I look forward to seeing more.



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