Keen 1-3: Add more graphics

ModKeen mods Tiles and Sprites in all episodes of Commander Keen.
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levellord
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Keen 1-3: Add more graphics

Post by levellord »

The EGAHEAD format is well known to the Keen community; it is a few variables followed by a list of all the graphics in the EGASPRIT and EGALATCH files and their offsets.

(I notice that Modkeen and lmodkeen leave the names blank when they create the EGAHEAD file, which makes things difficult.)

Now it's easy enough for Modkeen to add new bitmaps and sprites simply by modifying the k.lst file to include more. However, the game will not be able to use these as the offsets are not added to the EGAHEAD file. (Modkeen can also add extra tiles by enlarging the tiles bitmap, though usually the game can't access these either. (An exception is Keen 3, which has space for a larger tileinfo file, sadly, if you use the extra tiles patch, you cannot use lmodkeen to compress the graphics, as it's anal about tileset bitmap sizes. Booo!)

However, if you manually add the offsets of the new graphics to the EGAHEAD file (Time consuming indeed, but worth it for progress!) you can quite simply add (Or remove) as many new bitmaps and sprites as you want. (Until the game's memory is used up, which happens with too big graphics anyway.)

Therefore, in theory, if modkeen can be made to add these offsets automatically (Perhaps based on the number of bitmaps, or a .lst file.) then it should be simple enough to expand our sprite and bitmap space (Though mainly it'd be sprites that get added I should think.)

I've found that by removing unused bitmaps I can add around 20 new reasonable sized sprites to the sprite set, which allows for some interesting possibilities.
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Post by Stealthy71088 »

And each of these sprites can be patched to individually do different things? Do they follow certain base models (yorp, garg, vortikid, foob) or are you setting up the sprites from scratch?
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Post by levellord »

Forgive me.

What I meant was that it is possible to add new sprite *frames* and bitmaps (As used say by the title screen and the About Id screen.)

Sprites themselves use sprite frames, but we're usually limited to using only a few frames, say 4 to walk, 2 to jump, etc. It is not at present possible to add whole new sprites as these would need their own entries in the 'spawn sprite' space, and this is fixed in Keen. However, it is possible to heavily edit behaviors so that a sprite becomes a whole new sprite when shot say or uses a lot more animations than it used to. (The chain in Keen 1 can be made into a Yorp clone for example, and that will need a whole new set of sprites.)

So what I am talking about is the possibility of giving our existing sprites a whole lot more animations than they currently have.
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