Alchemy

This is a brief description of the ALCHEMY hack.

As always, the general intention is to enhance the enjoyability and playability of CF. In this code, I have created a system whereby players may assemble various ingredients to make artifacts.

The amount of work I put into this was substantial; other than new code – I created new archetypes, revised archetypes, altered the treasures file and created 2 new object types and a flag.

It therefore may be enjoyable to install this patch (incl code) and not define ALCHEMY in define.h. In particular, this patch does the following things:

• more varieties of potions are available in shops.
• new gems and types of food.
• monsters will now leave behind body parts when you kill them.
• if ALCHEMY is defined players may make potions/artifacts.

I have included instructions for installation, an install script and a brief document for using the code (pretty simple).

Finally, as always, feedback is appreciated.

b.t. thoma.nosp@m.s@as.nosp@m.tro.p.nosp@m.su.e.nosp@m.du

Player Instructions

Using the alchemy code (to make artifacts) is easy. You need the following things: 1) be able to use the alchemy skill, 2) have access to a cauldron, and 3) have the right ingredients.

To create an artifact, put ingredients in the cauldron, then use 'alchemy' skill. You might make something :) Backfire effects are possible. Books found in shops (and elsewhere) will give you formulae for making stuff. Of course, you can always 'experiment' on your own, but this may be dangerous.

Implementation Details

The bulk fo the alchemy code resides in 2 files - recipe.c and alchemy.c. The basic features of the code are:

• allow players to make artifacts from formulae. As players gain xp and levels, their ability to create stuff improves
• fast lookup of formulae. Lookup is randomized so that the list is attempted for a match based on # levels the player has. Obviously, higher level players get more attempts to match the list–and thereby have a grater chance of successfully completing a formula.
• There are ~80 formulae in this version. You can dump the formulalists using the crossfire -m7 option.

Basically, a simple linked list, ordered by the number of different archs in a formulae, is used to lookup 'recipe' matches. An indexed value for each formulae allows a quick comparison for a match with the cauldron contents. When a player casts alchemy on a cauldron, we first determine # archs inside the cauldron, pick the correct formulalist, randomly match against that list to see if we got a match. If matched, we remove the ingredients, and insert the artifact into the cauldron. Exp is awarded to the players alchemy skill (if they have it).