Tutorial #1
Poison: part 1 (get infected)

Today we are going to look at a simple Poison implementation. How it came about, and what we have done with it. Basically we are going to work in the following source files:
CGame:
cg_info.c
cg_local.h
cg_players.c
cg_weapons.c
Game:
ai_cmd.c
ai_dmq3.c
bg_misc.c
bg_public.h
g_active.c
g_combat.c
g_items.c
inv.h

OK..some explanations...... We are adding poison as a powerup, but we are also implementing the idea that f you are poisoned, you can pass it on as well. Like a virus so to speak. If I have poison, I sure as hell want other people to have it too..haha. So lets fire up VC, and open up the bg_public.h file.

SIDE NOTE: Pay attention to the coma usage towards the end of a typedef. If you forget to add a coma, or use an extra, you will get many-a-errors(TM).

Somewhere around line 222 there is a powerup typedef enum. looks like this:

typedef enum { PW_NONE, PW_QUAD, PW_BATTLESUIT, PW_HASTE, PW_INVIS, PW_REGEN, PW_FLIGHT, PW_REDFLAG, PW_BLUEFLAG, PW_NUM_POWERUPS } powerup_t;

We are going to add PW_POISON to the bottom of this. Inside the } bracket so....

typedef enum { PW_NONE, PW_QUAD, PW_BATTLESUIT, PW_HASTE, PW_INVIS, PW_REGEN, PW_FLIGHT, PW_REDFLAG, PW_BLUEFLAG, PW_POISON, PW_POISONED, PW_NUM_POWERUPS } powerup_t;

We add it this way to ensure that the current functionality of all powerups stays...

Also in bg_public.h look for a typedef named meansOfDeath_t (about line 446). Should read as follows:

// means of death typedef enum { MOD_UNKNOWN, MOD_GAUNTLET, MOD_GRENADE, MOD_GRENADE_SPLASH, MOD_ROCKET, MOD_ROCKET_SPLASH, MOD_PLASMA, MOD_PLASMA_SPLASH, MOD_LIGHTNING, MOD_BFG, MOD_BFG_SPLASH, MOD_WATER, MOD_SLIME, MOD_LAVA, MOD_CRUSH, MOD_TELEFRAG, MOD_FALLING, MOD_SUICIDE, MOD_TARGET_LASER, MOD_TRIGGER_HURT, MOD_GRAPPLE } meansOfDeath_t;

Now, this is the place the game defines what means of death there are... Obviously we are going to be able to die from poison, so we must add our own means of death. Should now read like this....

// means of death typedef enum { MOD_UNKNOWN, MOD_GAUNTLET, MOD_GRENADE, MOD_GRENADE_SPLASH, MOD_ROCKET, MOD_ROCKET_SPLASH, MOD_PLASMA, MOD_PLASMA_SPLASH, MOD_LIGHTNING, MOD_BFG, MOD_BFG_SPLASH, MOD_WATER, MOD_SLIME, MOD_LAVA, MOD_CRUSH, MOD_TELEFRAG, MOD_FALLING, MOD_SUICIDE, MOD_TARGET_LASER, MOD_TRIGGER_HURT, MOD_GRAPPLE, MOD_POISON } meansOfDeath_t;

For our MOD, we chose to have it use standard maps. Meaning, no special maps were needed. The MOD plays on every standard map out there. No one has to sit and change entities, or create all new maps to enjoy it. Thus we will be removing, and or changing quake 3's original items.

Now open up bg_misc.c from the game project. Around line 237 there is the rocket launcher definition. FoF replaces the rocket launcher with the Poison Powerup. This is what the original source should look like:

/*QUAKED weapon_rocketlauncher (.3 .3 1) (-16 -16 -16) (16 16 16) suspended */ { "weapon_rocketlauncher", "sound/misc/w_pkup.wav", { "models/weapons2/rocketl/rocketl.md3", 0, 0, 0}, /* icon */ "icons/iconw_rocket", /* pickup */ "Rocket Launcher", 10, IT_WEAPON, WP_ROCKET_LAUNCHER, /* precache */ "", /* sounds */ "" },

We are going to change the sound, model, icon, pickup name, giType, and giTag... For the sound we are going to use the holdable items .wav. Notice on our 5th line of code below. You can obviously choose any sound you like, but we liked that sound, and it was discrete Didn't let anyone know what you picked up. We obviously used our own model on line 6 and 7. The 0,0,0), on line 7 just tells the game there is only one model. No outer sphere or ring. etc.etc.etc. Line 8 of a definition in bg_misc.c is where it gets the icon for items. This first checks the known shaders to see if there is a reference to this icon. If not it looks in the named directory for the file. Line 9 defines the pickup name. This is shown to players when they pick up items, as well as bot AI. Line 10 determines the amount given. Here, since powerups are given for a length of time, the 30 has no meaning... Line 11 tells the game what type of item it is. We changed it from IT_WEAPON to IT_POWERUP because if you remember we defined PW_POISON inside the powerup_t earlier.

/*QUAKED weapon_rocketlauncher (.3 .3 1) (-16 -16 -16) (16 16 16) suspended */ { "weapon_rocketlauncher", "sound/items/holdable.wav", { "models/powerups/instant/poison.md3", 0, 0, 0 }, /* icon */ "icons/poison", /* pickup */ "Poison", 30, IT_POWERUP, PW_POISON, /* precache */ "", /* sounds */ "" },

Towards the bottom of the "gitem_t bg_itemlist"... after all the items but before (NULL)...

0, IT_TEAM, PW_BLUEFLAG, /* precache */ "", /* sounds */ "sound/teamplay/flagcap_blu.wav sound/teamplay/flagtk_blu.wav sound/teamplay/flagret_blu.wav" }, RIGHT HERE!!!!!! {NULL} };

We need to add the PW_POISONED info here as well as re-adding the rocket launcher item...just to ensure that quake 3's original coding still works. This way, if something references the rocket launcher...the game will not crash. This also takes care of the poisoned icon so you have a neat little HUD display for your ass getting damaged....So it should look like the following:

0, IT_TEAM, PW_BLUEFLAG, /* precache */ "", /* sounds */ "sound/teamplay/flagcap_blu.wav sound/teamplay/flagtk_blu.wav sound/teamplay/flagret_blu.wav" }, /*QUAKED power_poisoned (.3 .3 1) (-16 -16 -16) (16 16 16) suspended */ { "power_poisoned", "sound/items/holdable.wav", { "models/weapons2/shotgun/shotgun.md3", 0, 0, 0}, /* icon */ "icons/poisoned", /* pickup */ "Poisoned", 30, IT_POWERUP, PW_POISONED, /* precache */ "", /* sounds */ "" }, { "rocketlauncher", "sound/misc/w_pkup.wav", { "models/weapons2/rocketl/rocketl.md3", 0, 0, 0}, /* icon */ "icons/iconw_rocket", /* pickup */ "Rocket Launcher", 10, IT_WEAPON, WP_ROCKET_LAUNCHER, /* precache */ "", /* sounds */ "" }, {NULL} };

Model and sound do not matter for the Poisoned powerup as all we care about is the icon when you get poisoned and are taking damage......

That is about all for actually getting the powerup into the game. No lets continue on for what it should DO!!!

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