14 replies to this topic

[Foebane]

I always loved how dynamic the graphics in that game looked, and I figured out later it was due to repeated cycling through eight pre-defined character sets that defined the "frames" of the animation, probably by changing a POKE location to point to different parts of memory, ie. the start of each character set.

I once made a game that used the same technique and relied on collision with sprites for the action, wherein you have to collect treasure and avoid being hit by traps, and it worked brilliantly.

But that was years ago, and I forgot how I did it in BASIC...

I was just wondering what the technique was called.

[ZylonBane]

What do you call it when you use character sets to animate something?

I'm going to go out on a limb here and say it's called "character set animation".

Yeah I know, crazy, right?

[cbmeeks]

Character Set Animation is what it's called but you could also call it software sprites.

[Foebane]

OK, thanks. I'll accept that, probably as it's so obvious!

Did the Commodore 64 have the same ability? I've played Boulderdash on that as well, and apart from less choice in colours, seems identical to the A8.

Mind you, I've also played the ZX Spectrum version, which was unbelievably static and sluggish.

[ZylonBane]

cbmeeks, on Wed Dec 21, 2005 2:33 PM, said:

Character Set Animation is what it's called but you could also call it software sprites.

You could but you'd be wrong. "Software sprites" is using playfield graphics for your movable objects instead of hardware sprites. A single redefined character does not qualify as a sprite.

Edited by ZylonBane, Wed Dec 21, 2005 2:52 PM.

[Heaven/TQA]

ok. my 2 cents...

boulder dash is no high tech game as it simply uses some fonts which are used to generate the animation of the nasty's and the diamonds... i am not sure if the player is even a player/missle but i guess. i haven't looked into the source code yet...

so the font animation or character set animation is not a software sprite engine like we all know but the enemies like the butterlfies or the slime are software sprites... if you define a sprite as movable object... ok...you can not move it pixelwise and they are not background independent but i would call them sprites...

so don't mix the character set animation with the "sprites"...

[Heaven/TQA]

the c64 is nearly the same except some minor things (wasn't the scrolling not as good as the atari one?)

[Foebane]

Heaven, I'm not sure about the scrolling between versions.

But I am adamant that Rockford is NOT a player sprite on the A8. In fact, I think Boulderdash is one of those rare A8 games that uses no sprites at all.

[ZylonBane]

Heaven/TQA, on Wed Dec 21, 2005 5:21 PM, said:

so the font animation or character set animation is not a software sprite engine like we all know but the enemies like the butterlfies or the slime are software sprites... if you define a sprite as movable object... ok...you can not move it pixelwise and they are not background independent but i would call them sprites...

It's possible to build software sprites in character mode (see Super Pac-Man), but just moving a character (or set of characters) around doesn't make it a sprite. Otherwise that would make the cursor a sprite, which it clearly is not.

If you extend the meaning of "sprite" to anything that can move, you've made the term so broad that it's useless.

Edited by ZylonBane, Wed Dec 21, 2005 5:30 PM.

[Heaven/TQA]

zylon.... worth to think about...

[Heaven/TQA]

http://en.wikipedia....puter_graphics)

[Rybags]

Boulderdash doesn't really need sprites. All animation is done on character boundaries. It does use scrolling though, which easily explains why the C64 version is so much slower.

Apart from that, the only other trick is the scrolling colours in the diamonds, which is easily achieved by either flicking character sets (which both the 800 and C64 do equally well), or just changing the actual character data for the objects which are animated.

[TMR]

Rybags, on Thu Dec 22, 2005 3:42 PM, said:

Boulderdash doesn't really need sprites.  All animation is done on character boundaries.  It does use scrolling though, which easily explains why the C64 version is so much slower.

No it doesn't.

[Allas]

Both versions are really cool. Besides, Boulderdash is a 8-bit great game. Now, First Star launch boulderdash for mobiles phone and got the game number one. Very adictive.

[Foebane]

Rybags, on Thu Dec 22, 2005 4:42 PM, said:

Apart from that, the only other trick is the scrolling colours in the diamonds, which is easily achieved by either flicking character sets (which both the 800 and C64 do equally well), or just changing the actual character data for the objects which are animated.

No, I think there are complete character sets for each frame of animation. Only the walls, spaces, soil and boulders are not animated (why should they be?). But everything else - slime, warps, butterflies, diamonds and even Rockford himself are animated.

On the other hand, considering only half the graphics are animated, you are probably right. But I think Peter Liepa would've used the easier method of full-screen animation as I did in my own game.

Edited by Foebane, Thu Dec 22, 2005 4:44 PM.